Newsflash: Phased Out Lenses

Hello Alphanautics:

This is a quick newsflash related to the Alpha mount community.

Sony has finally phased out the 24-105mm f/3.5-4.5 and the DT 18-70mm f/3.5-5.6 zoom lenses. None appear anymore in the US SonyStyle site.

This means that if you were considering of buying any of those lenses, you can't do so now through authorized dealers or the SonyStyle sites, you'll have to resort to gray market (eBay and that kind of dubious places...).

There had been the persistent rumour that Sony was making a new 24-105mm lens, G class with SSM and what not, there were even photos of the manual around, but so far it hasn't happened.

Maybe Sony was waiting for all the stock on the 24-105mm to clear before releasing the new one or maybe it was just a rumour that turned out to be false.

The replacement for those lenses are the 28-75mm f/2.8 SAM lens and the DT 18-55mm f/3.5-5.6 kit lens.

The new 18-55mm lens has been receiving a lot of good reviews, putting it ahead of the 18-70mm in every way possible, although some criticism has been given to the SAM motor which apparently doesn't make things smoother or quieter or easier.

The 28-75mm has yet to be tested since it hasn't been released yet. It will be paired with the new A850 as a kit or be sold separately.

My only gripe is that if you're shooting full frame and zoom lenses with long reach are your thing, you'll have to hunt for the 24-105mm someplace else. Now the official option is the 28-75mm lens, which may be a bit short for some of you. Of course it all depends on what kind of photography you exactly do. And isn't that bad either, if you get a 70-300mm or 75-300mm telephoto lens, that one carries on where the 28-75mm left off.

Still, its better to have options no?

The kit replacement was inevitable, those are replaced more frequently than other lenses. The good thing is that the new one its better than its predecessor. Even though the focal length has been reduced, I think its a fair trade off if you're getting better optical quality. Head over at www.kurtmunger.com to read reviews of these and other Alpha mount lenses.

Over and out.

Wet Cleaning & Product Review: Dust-Wand Kit By Dust-Aid

Introduction

So far, I've written articles to deal with dust on your sensor using dry-cleaning products ( such as the Sensor Klear or an air blaster).

However, sometimes that is not enough, dust is persistant and stubborn and won't go away no matter how much you blow or use the Sensor Klear's tip.

That kind of dust is called welded dust.

Welded because it sticks to the sensor filter as if you actually took a welding torch and bonded it with the filter.

As with lose dust, this kind will appear when using small apertures, however, it can show up in two forms:

1.- Like a regular black dust spot

or

2.- Like a liquid drop when it dries out on a crystal surface. This kind is tricky, because sometimes you can mistake it for something else or you won't see it because its translucid (meaning it will let light through it but its not completely transparent).

Particles such as pollen or that have a sticky composition will weld into the filter. Another way of welding a dry dust particle is to blow inside the mirror chamber with the sensor exposed with your mouth. The water in your breath will work as a glue for the particle.

If this has or hasn't happened to you yet, rest assured, there is a solution to try before having to send it to the manufacturer.

And that's to perform a Wet Cleaning.

Wet Cleaning

A wet cleaning is basically the cleaning of the sensor filter with a liquid solution and especially made pads or cloths to rub the filter.

There are many ways to do this, the most popular is the Copper Hill method. Of course there are many other sites in the internet that can help you perform a wet cleaning, but this one is one of the most accurate.

The wet cleaning is usually regarded as a very difficult and/or risky process, and if it's the first time you do it, it will be.

Difficult because you got to be precise and fast in your movements, risky because you can make a worse mess on your sensor; you can move it out of place or spill liquid under the filter, and that would be BAD, because it would dry on the sensor itself, which means that all the pictures you take will have the pattern of the dried liquid and will require that you send it to the manufacturer so they can remove the filter and either clean or replace the sensor.

However, a well executed wet cleaning can get rid of all the welded dust attached your sensor, remove liquid stains and lose dust; leaving your sensor filter completely clean.

Just as its inevitable that at some point you WILL have to perform a sensor cleaning, it is INEVITABLE that at some point you will have to do a wet cleaning.

One problem of wet cleaning is the price of materials, they can be somewhat expensive and in the long run it may not be affordable to do a wet cleaning.

Another problem of the wet cleaning is that it's not as fast as blowing air into the mirror box or using a Sensor Klear. Not to mention that requires a clean place to perform the operation, otherwise it will be adding dirt over dirt...

The second point doesnt have much work around, but the first one does have a solution...

The charge of Dust bunny; my personal esperience

A few months ago I noticed a dust bunny (a.k.a. dust spot or dust particle) on the sensor filter of my A700, I blew and blew and blew at it with my air blaster, and just like the wolf from The Three Little Pigs, I ended getting nowhere...

Then I brought out my Sensor Klear and tried to remove it but it wouldnt budge either. I left it alone for a few days and tried again with the Sensor Klear, but the dust bunny had made a home in the sensor filter.

At this point I knew this meant only one thing... Welded dust, dreadful welded dust.

I was pretty much screwed because 1.- I didnt know how to perform a wet cleaning 2.- I didnt have anything to perform a wet cleaning and 3.- The dust bunny prevented me from using small apertures.

One small thing in my favor was that the dust bunny lost itself in the picture most of the time without being noticed, but if I used f/22 to f/40, it was visible if you know where to look for it.

I was pretty bothered at this because I thought I was staying ahead of the dust because I check for dust frequently and if there is, I blow it or rub it away. How this one got welded in particular, beats me.

I had to do a lot of reasearch about HOW to clean the filter using liquids, WHAT products to use and not to use and WHERE to get them. And when I say a lot of reasearch, I mean A L-O-T.

I found a lot of products to use but I needed something that included all the items I needed in one box, that was affordable and most importantly SIMPLE to use.

I kept coming across the items required for a wet cleaning separately in Amazon, and unfortunately the liquids I kept founding werent allowed in airplanes due to the fact they are flammable due to their chemical composition.

However, I came across a product called Dust-Wand Kit by Dust-Aid that included all the items needed to perform a wet cleaning, and all in one box.

So I decided to do some research about it.

I went to the official Dust-Aid site and researched the Dust-Wand kit, it seemed to be a good option to purchase for wet cleanings. However, I don't take everything the maker of a product says blindly, when trying to sell something, people will say whatever to convince you. Thats why the input of other people in this kind of stuff is needed.

I then tried to find reviews about this product and came up short of them, I guess because its a fairly new product, not many people have tried it. I kept finding mostly reviews by other users who got it and used it. As with all reviews, there were good and bad ones. Although the bad ones seemed to have happened due to a failure to follow the instructions contained in the box.

At this point it pretty much meant that I either went with it or kept looking. So I bit the bullet and purchased it.

Once it arrived, I reviewed videos, tutorials and articles related to wet cleaning. Then I watched the video by Dust-Aid about how to use their kit several times.

Once I felt sure enough, I did my first wet cleaning.

As of this point, I have performed two wet cleanings using the Dust-Wand kit with excellent results.

The Dust-Wand Kit by Dust-Aid

The Dust-Wand kit its a product from a company called Dust-Aid that offers sensor cleaning products, either for dry or wet cleanings. The Dust-Wand is obviously for wet cleaning.

The kit contains the following:

1. Travel case, red color


2. Instructions manual


3. Ultra Clean cleaning liquid (fast drying liquid)


4. 3 plastic wands (they come in different sizes to cover the different sensor sizes: 1.0x, 1.6x and 1.3x)


5. 3 cloth clips (these are used to hold the cloth on the wand once your wrap it)


6. Dust Cloths x 50 (this are the wipes that youll use to clean the sensor)

Things regarding the contents:

• Everything comes packed in zip lock bags, this is in order to keep the items clean. Don't throw those bags away!


• The Ultra Clean liquid is a fast drying liquid (the fastest on the planet according to Dust-Aid) so dont let too much time pass once you apply it. This liquid is safe for travel, so you can take it on airplanes with no problem. It also leave very little trace once it dries.


• The plastic wands are small so they wont clash against the mirror box walls, they come in different ratios to cover different sensor sizes: A200/300/330/700 use the 1.3x wands, A900 should use the 1.0x wand since its the biggest and meant to be used with full frame sensors.


• The Dust Cloths are said to be lint free but I have experienced this isnt exactly true all the time, some of the cloths will have it, but usually it will come up in parts that you wont use to clean the sensor.

Extra recommended items

Aside from the Dust-Wand kit, I will list a few items I consider that you also should have in order to have a successful wet cleaning, especially if its your first time:

a.- Latex gloves: Like the ones doctors use, these will prevent that you touch the cloth with your fingers in the center or elsewhere in the camera.

b.- Head lamp or a lamp: This will allow you to see the welded dust particles and to light the area you need to see.

c.- A magnifying glass: Especially those pocket magnifying glasses with light included. This will help you spot the dust particles and check if your sensor is clean once you perform a wet cleaning.

d.- An air blaster: It may happen that dust falls on the sensor while cleaning it or after you do but before you put the lens back, in that case, the blaster can get it out of the way quickly without having to clean again.

Finally, if you feel you need it, something to cover your mouth and nose, like those things surgeons use while operating. It prevents that you breathe into the mirror box, but again, only if you feel you need it.

How to use it

1.- You first have to put the wand and wrap it with the cloth included in the box. The exact procedure of how to wrap it is included in the instructions as well as in the video of how to use (which Ill link in the Links section). I wont put it here since it wont much sense unless you actually see how.

2.-.- Set the camera to Cleaning Mode

In the A100: Menu-> Setup (Wrench Icon) Page 3-> Clean CCD

A200/300/350: Menu-> Setup (Wrench Icon) Page 3-> Cleaning Mode

A700: Menu-> Setup (Wrench Icon) Page 3-> Cleaning Mode

A900: Menu-> Setup (Wrench Icon) Page 3-> Cleaning Mode

Cleaning Mode (or Clean CCD) locks the mirror up, opens the shutter and cuts power off the sensor for you to clean it.

DO NOT NOT NOT NOT NOT USE BULB SHUTTER SPEED UNDER ANY CIRCUMSTANCE.

This is risky AND stupid. Bulb is designed for long exposures NOT sensor cleaning. While its true that it opens the shutter and reveals the sensor as long as you keep the shutter button pressed, IT DOES NOT LOCK THE MIRROR UP NOR IT CUTS POWER OFF THE SENSOR, IF YOU ACCIDENTALLY REMOVE YOUR FINGER OFF THE SHUTTER BUTTON AND IT CLOSES, THE SHUTTER CURTAINS CAN CRASH AGAINST THE WAND AND THEY WILL GET BENT, THIS MEANS YOUR CAMERA IS RUINED FOR GOOD.

DO NOT USE BULB SHUTTER SPEED, USE CLEANING MODE.

3.- Remove the lens mounted on the camera and put it aside where its safe.

4.- Clean the loose dust that may be on the sensor filter, for this you can use an air blaster, a Sensor Klear or the Dust-Aid Platinum cleaner (more on that one later).

5.- Apply 3-5 drops of the liquid included (Ultra Clean) to each side of the wrapped tip.

6.- Place the Dust-Wand in the lower corner of the sensor filter and gently move it across the sensor filter.

7.- Remove the Dust-Wand and replace the cloth with a new one to insure you wont have any dust particles in the reverse cleaning. (Check the Notes of use section)

8.- Add liquid again to the tip, place on the upper corner of the sensor and clean.

Youre done!

As you can see, this is a fairly simple and quick procedure. It takes practice to become a master on it, but once you get the hang of this, you will spare yourself the trouble of sending the camera for a clean everytime you got dust since you can do it yourself.

Notes of use

• The instruction booklet includes diagrams as to how to wrap the cloth around the wand, how to move the wand on the filter, so if you couldnt picture it from the instructions above, dont worry.
• The liquid dries VERY quickly, so once you apply it, go straight for the sensor. A work around for this is to add 6-8 drops of liquid to the tip.
• I personally recommend wet cleaning only when its called for. Some sites recommend you do it weekly, but I feel that too much intervention too frequently on the filter may be more harm than good. If the blower and a dry cleaning dont work, then go for the wet method.
• The instructions recommend you also get a Dust-Aid Platinum for dry cleaning. The Dust-Aid Platinum is a stick with a sticky pad thats supposed to collect dust and other contamination from the sensor without damaging it. However, I cant vouch for the veracity of this, Ive seen the video of how to use it, but I personally dont feel that sticky pads are a thing you want to put in your sensor. I may be wrong, if anyone of you uses this product, let me know your experience.
• You will find a contradiction in the written instructions and in the video of how to use the Dust-Wand Kit. The instructions tell you to replace the cloth when going in reverse, but the guy in the video doesnt do this, he actually turns the wand and uses the same cloth. If you use the tip, then you will need to replace the cloth, but if you actually use the parts just below the tip, you can actually turn the wand around and avoid having to change the cloth. Ive tried this and it has worked perfectly for me. With this Im not suggesting you deviate from the instructions, just pointing out and letting you know the options. You decide what you do.
• One aspect that can turn confusing and requires A LOT of research is the kind of coatings the sensor filter uses. Why is this important? Because some wet cleaning liquids are meant for specifical coatings, not for everyone. The liquid in the Dust-Wand Kit is meant to be used with all Alphas since they all share the same coating. The Sony Alpha DSLRs use the ITO coating, ITO stands for Indium Tin Oxide, which is the chemical that the filter is coated with. For future reference also, if you cant remember the name of the coatiing, go with this, if the liquid you pick is safe to use with the Nikon D300, then its safe for the Alphas, since the sensor of that camera also shares the ITO coating.
• One important thing you will need to perform a successful wet cleaning is a clean room. By clean room I dont mean the one where sensors are actually mounted or records are recorded into the master plaques (in other words, 100% dust-less) If you could use one of these, great, go for it, but a more practical approach is this:

A clean room should be free of:

1. Air currents. Turn off the ventilators or close the vents.
2. Kids. Ask them out and buy them an ice cream if theyre nice and leave.
3. Pets. They let hairs loose into the environment. So take them out of the room.
4. Dust. Duh...
5. Anything that can distract you. This is a sensitive procedure, and you must put your full attention to it so you wont screw up. Whatever distracts you, get rid of it momentarily.

If you follow this, you shouldnt have a problem when cleaning the sensor on a well cleaned room in your house.

• I recommend that once youve done cleaning with the wet method, to test if the sensor is clean. For this do the following:

1. Use the smallest aperture possible on the lens your using. If it goes up to f/40, go there. Raise the ISO if you have to.
2. Set the exposure for 0EV or +1EV maximum. If your shutter speed is too slow (0.6" or slower) dont worry about it, the dust will come out even if there is slight movement in the photo. Just dont make the picture TOO bright otherwise the dust will be hidden in the highlights.
3. Focus at infinity at a white wall or the sky.
4. Take a shot, if theres nothing on it but color, then youre done, if there is a hair or dust spec, go to Cleaning Mode again and try getting rid of that with a blower or Sensor Klear. If it wont do, do a wet cleaning again.

• The gloves I recommended earlier are meant to be used when you manipulate the cloths, here's why: If you touch the middle section of the cloth with your fingers, the oils in your hand will be transfered to the cloth, therefore you will rub them all over the sensor. I recommend using the gloves so you wont touch any of the cloth with your fingers and eliminating the risk of messing the filter worse than already is. If you touch the center and clean the sensor with it and you notice, repeat the procedure for the cleaning but with gloves, the liquid will remove the oil stains.
• Make sure that you do this procedure from A to B with no stops in between. One reason is to reduce the time the sensor is exposed to the environment so it wont gather more dust, another one is to avoid light build up on the sensor itself, it may affect the Bayer filter in it and affect the colors the camera yields.
• If you welded dust that wont budge using the normal dosage of liquid, double it and soak the dust spec by placing the tip over it. In my experience when welded dust is soaked, it lets go easily when you brush it off with the wand.
• I recommend that if its the first time you do a wet cleaning, that you watch the instruction video several times, read this instructions and do a simulation of the movements youll need to do. This way youll be familiar with what you need to know so you dont have to interrupt the procedure when you actually do it.
• An important point: BE CALM when doing this procedure.
• The Dust-Wand Kit is safe for air travel.
• Finally, remember the Sensor Cleaning Axiom #1: IF YOU DO NOT TRUST YOURSELF OR DO NOT FEEL CONFIDENT ENOUGH TO DO A CLEANING PROCEDURE, DO NOT DO IT. TAKE YOUR CAMERA TO AN AUTHORIZED SERVICE CENTER OR LET A QUALIFIED PERSON TO DO IT.

Links

Dust-Aid's Official Site

Dust-Wand Kit

Contact Information

Instruction Video

Link to purchase it through Amazon US

Closure

No one likes to clean their sensors, but its a fact we have to deal with until someone invents a way to stop dust from entering the mirror chamber.

Now you know of the three ways I recommend for sensor cleaning: Air blaster->Dry Cleaning->Wet Cleaning. If all else fails, then you have to send the camera to Sony for them to deal with it.

Eventually you will have to do a wet cleaning, which is a trickier procedure than dry cleaning, but it can be done easily and quickly if you got the right tools and you know how.

The Dust-Wand Kit is a product Ive tried on my A700 with excellent results. The first time I used it it removed a spec of welded dust than had on my filter some time, the next one it removed some weird streaks that showed up on the pictures at small apertures. I still dont know how they got there, but they did and the Dust-Wand Kit got rid of them for good.

The good thing about the kit is that you can take it with you and perform a wet cleaning anywhere, just as you would with the Sensor Klear. The procedure isnt as fast as the dry cleaning, but its better to have the option available than having to wait to get home to perform a cleaning and either waste time post-processing your pictures to remove the contamination on your sensor or worse, miss the pictures due to a dirty sensor.

This product is therefore an Alpha Sight Recommended Product.

Finally, if you dont feel up to the ask to do a wet cleaning, dont ruin your sensor and leave it to someone who has done it successfully or take it to an authorized center. Dont risk a more expensive repair or having to replace your camera body.

I hope this article was helpful to you,

Until next time.

Product Review: Sensor Klear Cleaning System

An apology for the long delay in bringing you this article, Ive been busy and I couldn't work on it, but here it is now.

Introduction

One of the most important parts of your camera is the sensor.

The sensor is the part that work like film does in SLRs. It's the part that captures the image your lens is seeing.

However, unlike film, the sensor is fixed on its position, and its prone to get dirty.

Ever since the beginning of the digital age in photography, sensors have been getting dirty and it was a problem that camera makers addressed by implementing filters and vibrating mechanism to remove dust that attaches.

However, sometimes that's not enough and a more thorough cleaning is needed. This article will review a product that will help you clean your sensor in an easy and safe way.

How does a sensor gets dirty?

If you use a DSLR, eventually you will get your sensor dirty. Theres no way to avoid it.

Unlike P&S cameras that have their sensor locked and sealed within the body, DSLRs have it exposed, being protected only by the shutter. The sensor per se isn't exposed, you can see it, but in front of it, there is a filter that protects it. This filter is the one who catches dust and other contamination.

The first DSLRs didn't have any filter in front of the sensor, so if dust was around, the sensor itself caught it, which posed a problem when cleaning since there is dust that will go away with a blower and dust that will require more effort to remove. The dust that didn't go away with a blow could end up scratching the sensor, rendering it useless.

All the Sony Alpha DSLRs (A100/200/300/350/700/900) have a filter in front of the sensor, so there is no risk of ruining your sensor per se.

Dust is the most common form of contamination that a sensor can experience.

Every time you change your lens, the mirror chamber is exposed. Behind the mirror, there is the shutter (those black curtains that move when you take a picture), behind those curtains, there is the sensor.

The camera runs an electrical current through all of it in order to function, this includes the lens. The movement of parts (mirror, shutter, AF mechanism, etc.) generates static electricity.

This electricity attracts dust, dust is sensitive to this kind of electricity. If dust enters in the mirror box, its prone to attach to the filter in front of the sensor once the shutter opens to take a picture.

Since the sensor is running a current and the shutter curtains move, the dust has it easy to stick to it.

In theory, dust is the only contamination your sensor should experience, unless you wet it with something or stick something to it. Read this article for more information about it.

Effects of dust in a sensor

All camera makers do not want you to futz with the sensor if it gets dirty so you wont break or ruin your camera. The most recommended solution is to blow air into the sensor to remove it.

But there is dust that wont go away with a blow (and by blow I mean using a blower to do so, not your mouth since you can spit over the sensor).

So what happens when you have dust on your sensor?

The thing with dust is that you wont notice it if you use large apertures such as f/1.4, 2.0, 2.8, 3.5 and so forth. Since light is splattered all over the sensor, it conceals the dust.

However, if you close your lens up to f/11, 16, 22, 32, 40 and so, you will start to notice dark spots on your pictures. In a closed down lens, light is fed to the sensor in a more precise way, so if there is something in front of it, it will come out in the picture.

You can either use large apertures to avoid dust from coming out on the shot or clean your sensor.

Ignoring the issue is easier than doing something about it, but keep in mind this: If you ever require to use a small aperture in order to have as much Depth Of Field as possible or your camera selects a small aperture, your shot will show dust spots and you will have to waste time removing them with post processing software.

It's far better to deal with the issue so you have your whole aperture range at your disposal and not limited.

Cleaning methods

There are a thousand different ways to clear your sensor, some are just plain silly and will leave a worse mess than you originally had, some are very effective but require precise movements and time and above all, skill.

As Ive stated before, here in Alpha Sight the axiom I follow regarding cleaning sensors is:

IF YOU DO NOT TRUST YOURSELF OR DO NOT FEEL CONFIDENT ENOUGH TO DO A CLEANING PROCEDURE, DO NOT DO IT. TAKE YOUR CAMERA TO AN AUTHORIZED SERVICE CENTER OR LET A QUALIFIED PERSON TO DO IT.

This is in order to avoid that you make things worse or ruin your equipment for good when trying to clean it.

The scope of sensor cleaning is vast and wide, this article will focus only in one. If you would like to learn more about other sensor cleaning methods, check out the links at the right side of this blog, ask in photography forums, and surf the net. There are plenty of answers out there.

Finally, if you rather leave this in expert hands, you can look for a Sony Authorized Service Center or take it to Adorama or Calumet Photo.

If you want to learn an easy way to clean your sensor, keep reading.

The Sensor Klear by LensPen

If you read the previous article, you will see a review of a cleaning product for lenses called LensPen.

Well, the company that produces that item, also produces items to clean other camera parts, including the sensor.

Their product is called Sensor Klear.

The Sensor Klear is similar to its LensPen cousin, its the size of a pen, although a bit smaller and thinner than the classical LensPen.

It's made of a retractable brush and a cleaning tip with the same carbon based compound that the LensPen has. For those of you who don't know, the tip is made of carbon, similar to the one found in pencils or in the ink of newspapers. The ink contains carbon, and the carbon absorbs impurities.

Unlike other methods (like the wet one) that require flammable fluids or tissues or swabs, the Sensor Klear doesn't create waste. And it's safe to take it on planes, whereas the liquids used for cleaning sensors with the wet method aren't allowed.

The cleaning tip of the Sensor Klear is smaller than the one in the LensPen, but there is a reason for that; it gives you more control over the handling of the tip when you clean the sensor.

Whereas on a lens you have a broad space to work with, on a sensor is different, you got to be careful not to mess with other components inside the mirror box. Having a smaller cleaning tip allows you to move the Sensor Klear just enough to clean the sensor and avoiding touching something else.

There is another feature to the Sensor Klear's cleaning tip: its in a triangular shape. This is done to allow you to clean the corners of the sensor if its required, if it had been a circular shape, you wouldnt reach the farthest corners of the sensor, and if you got dust there, it would be a problem.

To maximize the usefulness of the Sensor Klear, the head bends in order to give you flexibility in case you need to move the pen in an angle.

How to use it

1.- Set the camera to Cleaning Mode

In the A100: Menu-> Setup (Wrench Icon) Page 3-> Clean CCD

A200/300/350: Menu-> Setup (Wrench Icon) Page 3-> Cleaning Mode

A700: Menu-> Setup (Wrench Icon) Page 3-> Cleaning Mode

A900: Menu-> Setup (Wrench Icon) Page 3-> Cleaning Mode

Cleaning Mode (or Clean CCD) locks the mirror up, opens the shutter and cuts power off the sensor for you to clean it.

DO NOT NOT NOT NOT NOT USE BULB SHUTTER SPEED UNDER ANY CIRCUMSTANCE.

This is risky AND stupid. Bulb is designed for long exposures NOT sensor cleaning. While its true that it opens the shutter and reveals the sensor as long as you keep the shutter button pressed, IT DOES NOT LOCK THE MIRROR UP NOR IT CUTS POWER OFF THE SENSOR, IF YOU ACCIDENTALLY REMOVE YOUR FINGER OFF THE SHUTTER BUTTON AND IT CLOSES, THE SHUTTER CURTAINS CAN CRASH AGAINST THE SENSOR KLEAR AND THEY WILL GET BENT, THIS MEANS YOUR CAMERA IS RUINED FOR GOOD.

DO NOT USE BULB SHUTTER SPEED, USE CLEANING MODE.

2.- Remove the lens mounted on the camera and put it aside where its safe.

3.- Hold the camera body firmly and position it in a downward angle to prevent dust or other materials from entering the mirror box.

4.- Use the retractable brush on the Sensor Klear to remove any dust on the lens mount. Make sure you retract it back when you're done with it.

5.- Use a high quality air blaster to blow away dry and easy-to-remove dust from the sensor.

Note: It may happen that by doing this, the dust particles on your sensor may be blown away and that's it, no more cleaning required. However, make sure you don't blow the dust into the mirror or inside the viewfinder. If it lands on the mirror, use the brush gently to remove it. You will only notice if its on the mirror or the viewfinder once you turn the camera OFF and the mirror comes back down and you look through the viewfinder. If you see spots, its in one of those two. Blow or brush it away. Keep in mind that dust in those places WILL NOT show up in the picture.

6.- Use the Sensor Klear's cleaning tip to remove any dust, stains or oil from the sensor. Play close attention to the corners. If you used a blower, dust may have moved to the corners and hide there.

7.- Once you're done, put the cap back on the cleaning tip and give it two twists to leave it ready for next time.

8.- Use the brush to remove dust from the rear element in your lens if there's any. If you see finger prints or something else, you will need a LensPen to remove it.

The cleaning tip

Inside the cap, you will find a foam pad, that is the replenisher that contains the carbon compound, everytime you use the Sensor Klear make sure to put the cap back on and give it two twists to replenish the cleaning tip for next time you need to clean the sensor.

Notes of use

Here are some points to keep in mind when using the Sensor Klear:

• It's possible that one pass with the Sensor Klear won't do. Sometimes dust is sticky and requires more passes to remove. Keep using the Sensor Klear until the sensor is completely clean.
• The test to find dust on your sensor is: Point the camera to a white piece of paper or at the sky at infinity focus, select f/22 or a smaller aperture and take a picture. If there are spots, there is dust. When you clean your sensor perform this test to confirm your sensor is clean or if there are still spots to be removed.
• It's possible that you clean dust on one part of the sensor and it shows up on another part. If this happens, do a thorough cleaning of the whole sensor to ensure that no dust is left behind or just moved.
• Again, DO NOT USE BULB SHUTTER SPEED, USE CLEANING MODE.
• Do NOT use the brush to clean the sensor, use only the cleaning tip.
• The Sensor Klear lasts 50 uses.
• There are replaceable heads in case you use it 50 times, you just pull the tip off and insert the new one.
• The Sensor Klear is advertised to work with CCD sensors, it also works with CMOS sensors.
• DO NOT TOUCH THE BRUSH WITH YOUR FINGERS, YOU MAY ADD SKIN OILS TO IT AND IT WILL STREAK WHATEVER SURFACE YOU USE IT ON.
• DO NOT TOUCH THE CLEANING TIP WITH YOUR FINGERS EITHER.
• When using it, do NOT press hard against the sensor or the mirror, you may disalign them and that is B-A-D.
• It's recommended that you use a clean environment with no breezes.
• I recommend using a strong light and a magnifying glass to see what youre doing. The company that produces the Sensor Klear is about to release a magnifying glass designed for sensor cleaning as well.
• Use latex gloves and a gown if possible, this will reduce the chance you will touch something you shouldnt and ruin it or breathe or sneeze over the mirror box and/or sensor.
• Do NOT blow the sensor with your mouth, your breath contains saliva, which may end up falling over the sensor. If it does, use the cleaning tip.
• DO NOT USE CANNED AIR UNDER ANY CIRCUMSTANCE. Canned air has been proved to contain all sorts of particles on it and you may end up giving those to your sensor.
• The Sensor Klear is environmentally friendly, it doesnt create waste nor it requires flammable liquids, swabs, tissues, etc.
• The Sensor Klear reduces static build up on your sensor, this will help to reduce the amount of dust being pulled towards your sensor.
• A blower is recommended with this product because sometimes dust will go away before you use the Sensor Klear.
• Clean your sensor only when necessary, check for dust every month and remove it as soon as you find it, the longer dust stays there, the harder it is to remove.
• Finally and again: IF YOU DO NOT TRUST YOURSELF OR DO NOT FEEL CONFIDENT ENOUGH TO DO A CLEANING PROCEDURE, DO NOT DO IT. TAKE YOUR CAMERA TO AN AUTHORIZED SERVICE CENTER OR LET A QUALIFIED PERSON TO DO IT.

Links

Official Site

Sensor Klear

How to use the Sensor Klear presentation

Contact Information

Link to purchase it through Amazon

Closure

Sensor cleaning is a tricky business. If done well, it's not an issue, but for the inexperienced it can be something terrifying to do.

Methods to do it there are by the boat load, but the few that really work need practice and skill.

The Sensor Klear is an easy way to clean your sensor quickly and with no hassle if done correctly.

To have a dirty sensor these days can be a problem, especially if youre not aware of it. It may present a problem when you least expect it and you will need to waste time removing dust spots from your pictures in post processing.

You may ignore the issue using large apertures, but like I said, one day you will need to use a small f/stop and you will be in trouble.

The Sensor Klear is a method that works everywhere and you can always take it with you since it doesnt take much space at all. And the procedure is really simple and doesnt require special liquids or swabs or whatever. You can travel with it since its completely safe.

This product is therefore, an Alpha Sight recommended product.

Finally, if you purchase this item and you've never cleaned a sensor before, read this whole article again, read this article as well too. Read and watch the presentation at the official site. If you have any questions, you're always welcome to ask me.

And remember, if you dont feel confident enough to clean your sensor, DON'T, leave it to someone who does know what he is doing.

Until next time.

Product Review: LensPen Cleaning System

On this article, I will review an item for lens cleaning Ive personally used: The LensPen cleaning system.

Introduction

As I mentioned before, your lens is bound to get dirty at some point, unless you use a protective filter. In that case, the filter will get dirty instead of the lens, but the fact remains that something will get dirty.

There are very common procedures to clean a lens when it gets dirty, but theres the risk you may end up doing a worse mess with them.

In my interest of preventing that a mess happens to you, Im bringing you this review you may want to consider if you need a fast, easy and safe lens cleaning option

The LensPen

Recently I used a product called LensPen to clean my Sony 18-200mm that had some liquid stains and dust on the front element and a Kenko special filter that required a good cleaning.

The LensPen is a device the size of a pen (ergo the last suffix on the name, duh :) ) which has a retractable brush on one side and a cleaning tip on the other one.

Unlike other cleaning products, the LensPen doesnt pose a threat to the lens' glass nor will it make things worse. It's proven to remove finger prints and leave no trace of them.

The LensPen works under the same concept used by people who clean glass with newspapers. Newspapers have ink, which in turn contains carbon, carbon absorbs impurities and removes them without leaving marks.

The LensPen cleaning tip contains a carbon compound that removes skin oils and other stains on your lens without leaving any marks. The brush on the other side is designed to remove dust and other lose particles that can be easily removed.

The cleaning tip is flexible, which allows you to reach the edges of the lens easily, the brush is retractable, keeping it safe from getting damaged while transporting it or from your fingers.

It's portable since it doesnt take too much space, easy to use and safe for your lenses.

How to use it

1. Begin by removing any dust or lose particles on the front element. For this you have to use the retractable brush.
2. Remove the cap covering the cleaning tip and wipe the lens with smooth and circular movements with the tip. If there are smudges or stains that persist, you can breathe gently on the lens and repeat the process. (Believe it or not, this works, tried this myself)
3. Put the cap over the cleaning tip again and give the cap a half twist to replenish the cleaning tip.

The cleaning tip

The cleaning tip is what contains the carbon compound that cleans the glass surface. Inside the cap you will find a foam pad, which is the replenisher. Everytime you use the LensPen, you have to replenish the tip to keep it working.

Notes of use

Here are some things to keep in mind when using/about the LensPen:

• The LensPen is designed to work with camera lenses, videocamera lenses and small camera lenses, rifle scopes, microscopes, night vision googles, telescopes, etc.
• The LensPen has a life of 500 uses (Although it may vary depending on what kind of contamination is present on your lens)
• Do NOT use it on wet surfaces
• The LensPen is environmentally friendlier than other cleaning methods since it wont require solvents or other liquids, tissues and creates no waste.
• The LensPen isnt exactly designed to clean eyeglasses due to the fact that eyeglasses have concave and convex design, but you can give it a shot.
• DO NOT TOUCH THE CLEANING TIP OR THE BRUSH WITH YOUR FINGERS
• In order to prevent the previous point from happening, use gloves when using it
• The compound will not spill or dry out
• The LensPen is reported to reduce electrostatic charge. (This is a cool feature, because electrostatic charge is the thing that says to dust: Hey , over here!. If you wonder how can a lens can get static electricity, heres how: by moving it, when it gets rubbed in transport, when plugged to a camera)
• The LensPen may leave a black mark on your finger but not on the lens, this is because of the carbon compund. Like the lead found in pencils.
• If there an excess of cleaning compound on the tip, it may leave traces of it on the lens. This is fixable by blowing the compound away from the lens with an air blaster and patting the tip on a soft cloth.
• The official site says there are some bogus LensPens out there not made by the official company. To know if your LensPen is legit or not look for the words: "Distributed under the authority of Parkside Optical Inc., Vancouver, Canada" and the official hologram on the backcard.
• If you need the clean a small lens, you should consider the MiniPro LensPen which is designed for smaller lenses.

Links

Official Site

Optics Cleaners

FAQ

Comparision with other systems

How to use the LensPen and Information presentation

Contact Information

Link to purchase it through Amazon

Closure

The LensPen is a cheap and easy solution to clean your lenses when they get dirty. Since its portable, you can take it with you without worrying about space in your bag.

Having clean equipment has become critical and practically a necessity for photographers everywhere, the option of being able to do it immediately give this method a huge advantage over other systems. Theres also the fact that you dont touch the cleaning element with your hands, as you do with tissues or cloths.

This product is therefore, an Alpha Sight recommended product.

Coming up next, a product to easily clean your sensor: the Sensor Klear.

Visual Guide To Change Focusing Screens On A900

One great feature of the A900 is that you can change the focusing screen without having to send your camera to an authorized repair center.

If you own an A900, this video guides you step by step on how to change the focusing screen yourself.

The focusing screen is that piece of glass that goes over the mirror that has the lines you end up seeing in the viewfinder. It can be changed to one that has a grid and the points of composition in compliance with the rule of thirds, or a plain but bright one for manual focusing.

You can find the Focusing Screen Type L and the Focusing Screen Type M in SonyStyle.

Bear in mind that the A900 is the only Alpha DSLR that allows the owner to change the focusing screens, the rest of the Alphas can have the screen changed, but only by authorized personnel, otherwise it may void your warranty.

If you attempt this kind of procedure, I suggest you watch the video a few times before proceeding. Get a good idea of what you need to do, practicing the movements first is also recommended.

Lenses-How To Pick One And Read Their Specs: Part 3

Technical data not explained in a lens explained

Lens groups/elements: A lens may seem to be built in a complex way, but in reality its made up of smaller lenses inside it called simple lenses. These lenses are shaped in a specific form so they will create the effect required. When packed together inside the lens, they combine to make the lens you end up holding.

The arrangement of these simple lenses can be in groups or by their own, depending on the lens construction and what kind of lens it is. Each simple lens is called element and a group of simple lenses its called lens group.

When you buy a lens, in the technical specifications its stated how much lens groups and/or elements the lens is made of. Depending on the maker, a lens may contain little or a lot of elements inside it.

Minimum focus distance: In order to bring things in focus, a lens needs to have the proper distance from the subject. There is a limit to how far or how near the subject needs to be from the lens in order to be in focus. The minimum focusing distance is how much distance there HAS to be between your subject and your lens in order to be properly focused. If you dont have this distance, you wont be able to focus.

Unlike high end P&S cameras that require a lot less minimum focusing distance, DSLRS require more, this is determined by what kind of lens youre using and the size of your sensor. Since P&S cameras have a much smaller sensor, they have a much more cropped view, so close ups can be done with the lens practically over your subject.

The only lenses in DSLR system that can do close ups from really close to your subject are macro lenses. The minimum focusing distance varies from lens to lens, its not the same or standard among them, only if you own two identical lenses.

It's important to know this distance for every lens youve got so you know how close you can physicially get to your subject before the lens can't focus. It will spare you of losing moments you may not get back.

Filter diameter: Almost all lenses have a marking in them that tells you what size the front element is so you can attach a filter. The symbol is this one: Ø. This symbol comes with a number. In the Sony 28mm f/2.8 it comes like this: Ø 49mm. This means that if you want to attach a filter to this lens, you need a 49mm sized filter. The Sony 18-200mm f/3.5-6.3 shows Ø 62mm. The lens is bigger than the 28mm, therefore it requires a 62mm filter.

Since lenses vary in size, they size of filters you will need changes a lot. This makes it a problem if you want to put filters on all your lenses, since the variance in sizes may result in one filter being more expensive than others due to rare size or lack of filters due to the size.

Whenever you plan to attach a filter keep in mind two things:

1. First check if your lens has a thread on its edge to attach a filter.
2. If you attach a filter, be gentle when attaching and disattaching it. Some lenses have threads more delicate than others, and if youre not gentle, you make break them. This can result in no longer being able to attach a filter and need to buy a new lens.

Finally, some lenses like the Sony 16mm Fisheye lens or the 500mm f/8 Reflex lenses have built in filters included.

Size and Weight: As part of the technical specs of any kind of gear, the size and weight is included. This can be helpful if youre looking for a light and small lens or a big and heavy one. Checking this information before purchasing (especially online) can be helpful to give you an idea of the real size and weight of the lens, since it's common in online stores to display big lenses in a small size and small lenses in a very big size or not display them at all.

Minimum aperture: Since youre more likely to use big apertures instead of small ones, those are included in the lens itself, however, the minimum aperture or big f-number is something you should also know, since it tells you just how dark the lens can be or how much Depth Of Field you can achieve with it (assuming you can have enough light for such small apertures).

Just as the maximum aperture can change if you change focal length, the same happens with the minimum aperture. In the Sony 18-20mm f/3.5-6.3, the maximum aperture at 18mm is f/22, whereas at 200mm its f/40.

In average, in the Sony Alpha lens range the maximum aperture at a lens' shortest focal length is f/22 and at the largest focal length is f/32. Keep in mind this is just an average, not the exact aperture number for each lens.

Angle of view: A very important feature of any lens, its the angle of view it possesses.

The angle of view is basically how much of the scene infront of it the lens can see. The bigger the number, the wider the angle, and the smaller the number, the tighter the angle.

Wide angle lenses have (obviously) wider angles (duh) than zoom lenses or telephotos. However, that depends on the focal length of every lens. If you got a wide angle lens like a 20mm but you also got a zoom lens that has a short focal length of 18mm, the zoom lens can see a bit more than the wide angle lens.

Zoom lenses at their biggest focal length and telephoto lenses have a small angle of view, this is because in order to compress distance and bring subjects closer, you got to sacrifice angle of view. This explains why the closer you get to something, you cant keep the surroundings inside the frame.

How much angle of view you need depends on how much of a scene you want in your picture. You may have a wide angle lens thats including too much in the picture that you dont want or a zoom lens that cant squeeze an extra person in the frame.

One thing you got to keep in mind here is that the angle of view of a full frame lens changes when you use it on a APS-C sensor camera. Remember what I said of focal length multiplier? It applies here. Since a smaller sensor crops out part of the scene that a full frame sensor could capture, this also changes the angle of view.

Example: The Sony 16mm f/2.8 Fisheye lens is designed for a full frame sensor. On a A900, that lens would have an angle of view of 180 degrees, which would make the edges of the frame take a circular shape. If you use that lens on a A700 or else, the angle is reduced to 110 degrees and you wont be able to get the fisheye view the lens is designed to give.

This is why APS-C sensors require specially made wide angle lenses and fisheye lenses. Due to the cropping the sensor does, you would need a lens like the Sony 11-18mm f/4.5-5-6 or a Sigma 10-20mm whereas in full frame a 12-24mm would work as wide angle.

Whenever you buy a lens, be sure to know the angle of view the lens has and if it will be reduced if you mount it on a APS-C sensor or smaller.

Number of aperture blades: In a lens, the more blades it has, the better picture quality since the degree of blurring it can achieve is better.

Another data thats specified in the specs its if the aperture is normal or circular. Circular aperture is better since it renders the out of focus subjects smoother than the normal aperture.

In the Sony Alpha range, the average aperture blade number is 7, and the G and Carl Zeiss lenses almost all have 9. Also worth mentioning is that almost all the lenses in the Alpha line have circular aperture, the 28mm f/2.8 is one of the exceptions.

If it has special glass elements or coatings: Usually lens makers include special lenses among the elements to correct possible light aberrations that can occur. One very common these days is the APO lens. APO is an abbreviation of apochromatic, which means it corrects the color aberrations that the other elements can cause. The APO lens element was an element used by Minolta in its range of telephoto lenses.

There are all sorts of special glass elements used by lens makers in order to correct aberrations or to further enhance the effect the lens is designed for. They usually specify them when promoting a lens.

As for coatings, whenever the lens maker doesnt specify if the lens has a special coating on the lens, it will on the specifications.

Magnification ratio: Another important value of a lens is its magnification ratio.

In simple terms, it means how much it will enlarge small things. This is something really important in macro lenses, since they are designed to enlarge things.

When you see something through a lens, its size can increase or decrease. The magnification ratio is how much that lens can bring subjects to their real size. This ratio is expressed like this: 1.0 or this 1:0.

When a lens says its magnification ratio is 1.0 it means it shows the subjects on their real size.

Magnification comes in all lenses, in some its not so visible and in others it is. However, even telephoto lenses can have a high magnification; the Tamron 70-300mm f/4-5.6 LD Di has a magnification ratio of 1:2. That means that it can make subjects appear half their real size, which effectively makes this lens into a telemacro lens: a telephoto with macro capabilities.

If it comes with any other accesories: Some lens makers supply their lenses with additional accesories such as lens hoods, carrying cases, filters, cleaning cloths, etc. It's important that you check if any accessory is supplied with every lens you purchase, otherwise you wont know if something is missing.

Questions about lenses that you have but you're afraid to ask

Does an expensive lens guarantees a good photo?

No. An expensive lens may have a lot more bells and whistles than a cheaper lens wont have, but no matter how fast, light, full of special glass, etc. the lens is, if the photographer doesnt know how to handle it or doesnt have the enough vision to create a compelling picture, not even the most expensive lenses in the world will guarantee a good picture. It all depends on the photographer and its creativity.

Is lens sharpness that important?

It's common these days for photographers to be really picky about lens sharpness. The holy grail is a lens thats sharp all around including corners and at any aperture.

The truth is, such thing hasnt existed so far, and probably will never exist.

Modern lenses are sharp enough to get good pictures, sure, some are sharper than others, but the only way in which you will scientifically measure how sharp a lens is from another is with controlled tests at a lab.

And a lab isnt the only place for photographs you can use.

Ken Rockwell points out on an article he wrote about sharpness that usually the problem is not the lens, but a bad focus, camera movement or subject movement. You can find the article here.

Sure, you dont want your pictures coming out fuzzy or not sharp enough to see the subject, but lenses these days wont fall into that unless they have a defect.

A very very very underrated lens is the Sony 28mm f/2.8. A lot of people and testers disregard this lens because its not as sharp as other more expensive wide angle lenses are.

The truth is that this lens is sharp, may not be sharp enough to cut bread, but it sure is sharp, and Ive managed to get great portraits with it indoors.

Again, its more important what you conjure up for a picture than if your lens is sharp as a shark's fang.

Is it best to go for the expensive lens instead of the cheap one?

Well, if you got money to blow, then get the expensive one, if not, the cheap one.

Price only determines three possible things in a lens: Status, quality and options.

You can buy a Sony 70-300 f/3.5-5.6 G lens and blow 800 dollars on it instead of the Sony 75-300 f/4.5-5.6 that costs 223 dollars, you will be seen as someone with serious equipment and youll have as many buttons on the lens as you do on your camera.

However, that doesnt mean that you will get great pictures with it if you dont know how to use it. You only got a long lens with lots of buttons, better glass and a lens hood that will surely scream out to everyone else: HEY, I GOT AN EXPENSIVE LENS!

To get great pictures you dont have to own the best lenses. To think that you need the best lens to get better pictures is just as stupid as to think you need an Aston Martin or a Ferrari to make it to work on time.

Its the results you create with a lens that get you awards, jobs or praise. Viewers dont think of what lenses you use when looking at your pictures. They watch the results.

A 1800 dollars lens like the Carl Zeiss 24-70mm f/2.8 T* Vario Tessar wont make you a better photographer, nor will create masterpieces nor will take pictures on its own. The only results it will get depend on what you do with it. What YOU do with it.

Expensive or cheap? Doesnt matter, its the result you get from it that counts.

Closure

This concludes our article about how to pick a lens and read their specs. I hope that now the basic terms and concepts are now clear to you and you can get a better idea of what to look for in a lens when you purchase one.

And remember, its what YOU the photographer do with a lens that matters, not the lens itself. If you ever won a prize, it certainly wouldnt go to the lens you used, would it? A lens doesnt do anything on its own afterall.

James Bond uses a Walther PPK 7.65mm gun, which is a tiny gun, and yet he always does his job. Its how you use it, not what brand or size.

Until next time.

Lenses-How To Pick One And Read Their Specs: Part 2

Basics explained

1- Why does the Sony Alpha DSLR system doesn't need stabilized lenses?

The Sony Alpha DSLRs use a different approach to stabilize an image than the one used by other camera manufacturers.

In simple terms, the Alpha use sensor stabilization, which means that when the camera senses movement, the sensor is kept as still as possible by motors inside the camera. This helps to reduce the blur seen in pictures when the camera is hand held.

The difference between this system and stabilized lenses is that all the lenses you purchase will have access to the sensor stabilization at no extra cost, making them lighter and cheaper in some cases. DSLR systems that require stabilized lenses require you to purchase each lens with stabilization or vibration reducing motors, which can make them heavier and some times more expensive.

2.- What is a bayonet mount and why Minolta and not Sony developed it?

In photography, the interface used to make a camera and a lens fit and talk to each other is called lens mount. There are screw driven mounts (like the one used in lenses you can attach to P&S cameras), friction lock and bayonet mounts.

A bayonet mount is the most used type of lens mount in DSLR cameras due to the fact that they align precisely the electronic and mechanical components of the lens. It's called bayonet because it's based on the military weapon of the same name. When soldiers needed to attach a bayonet to their rifles, they could do so quickly because of the mounting system. This also applies to photography since DSLRs allow you to change lenses much faster than a screw driven mount.

The Alpha mount was originally the Minolta AF mount, which was the first lens mount to auto focus, this mount was introduced in 1985. When Minolta had to close down operations, Sony purchased most of Minolta's assets, including lens designs, the flash mount and the lens mount. Sony rebranded the Minolta AF mount in to Alpha mount and added further improvements, such as addition of lens contacts in the mount for better camera-lens communication and the use of lenses with the flash ADI function.

All the Minolta AF lenses fit the current Alphas because they all work on the same mount. Minolta lenses older than 1985 can't be used on the Alphas unless you do some custom work on the mount to make it fit.

Lens information explained

This section will explain the items listed in the section Reading a lens of Part 1.

Maker: This states who made the lens, Sony, Minolta, Tamron, Sigma, Carl Zeiss, etc.

Focal length: A lens can zoom or not, but they all got focal length. In simple terms, focal length is how much space there is between the sensor and the lens. The less distance, means a wider angle of view, the more distance, it means the lens can reach far in the distance.

Example: The Sony 18-200mm lens tells you it has a variable focal length. It's shortest distance is 18mm and the longest end is 200mm. At 18mm the lens will have a wide angle field of view whereas at 200 it will have a very narrow view. This is an all purpose lens, which means that can be used to take portraits, landscapes or telephoto shots because of the wide distance range it covers, however this makes it bigger and heavier than other lenses, like the 18-70mm.

Example 2: The Sony 50mm is a fixed focal length lens (lenses with fixed focal lengths are called primes), this means there is 50mm between the sensor and the lens. The field of view is fixed, and to zoom or have a wider angle, you need to move back or forth physically. This focal length is often used for portraits.

Example 3: The Sony 11-18mm is a super wide angle lens with a zoom range. The widest distance is 11mm and the longest distance it will go is 18mm. This lens is designed to take wide angle shots but you can zoom in or out to allow more or less of the scene to be captured. It can't take shots farther than 18mm because it's not designed for that.

Example 4: The Sony 500mm lens is a super telephoto prime lens. You can't move its focal length and everything you will see with this lens will be at 500mm, which will make far things really close to the view. You cant shoot nearby subjects unless they are within the focusing distance of this lens.

Example 5: The Sony 18-70mm is a zoom lens, usually sold as part of a kit. It has a wide angle distance of 18mm and a telephoto distance of 70mm. This lens doesn't have a long reach like the Sony 18-200 or 18-250. It is designed as an all purpose lens which covers enough distance for portraits or landscapes without being too heavy. Since it's usually the first lens most Alpha users get, it teaches them how to pick what focal length to shoot at. Eventually the user will need more or less focal length for different shots and that's when they move to other kind of lenses with different focal lengths.

So when you see a lens with 1 focal length number on it, it means its a prime lens and the zoom changes as you move, if you see a lens with 2 focal length numbers on it, it displays how short and far it will go.

Maximum constant aperture or variable depending on focal length: A lens can or can not keep a constant aperture at a given focal length. It depends on it's construction, lenses that can keep a constant aperture are usually a lot bigger and heavier than one that has a variable aperture.

But what does this mean?

All lenses have a maximum aperture number, such as 1.4, 2.8, 3.5, 4, 8, etc. Having a big aperture increases the amount of light that reaches the sensor and reduces depth of field (how much of the subject is in focus). Depending on the lens construction, the lens can hold on to the maximum aperture even if you zoom or not.

Example: The Sony 70-200 f/2.8 lens its a telephoto lens that can keep the aperture at 2.8 in all the focal length range, be it 70, 100, 150, or 200mm. This is really helpful because if you're shooting under low light and you need to zoom and keep the f number at 2.8, the lens will be able to keep it, giving you the necessary light to work with. The downside of this lens is that is bigger and heavier than other telephoto lenses.

Example 2: The Sony 75-300mm f/4.5-5.6 its another telephoto lens, but this one has a variable aperture. At 75mm, the lens biggest aperture will be f/4.5, but if you zoom at 300mm, the lens' maximum aperture changes to f/5.6. Why does it happen? The lens construction doesn't allow the lens to keep the aperture constant, therefore it has to change when the focal length changes. The plus point of this is that lens size is not too big and heavy, but you have to sacrifice light if you zoom in.

Example 3: The Sony 18-250mm f/3.5-6.3 its a zoom lens with variable aperture. At 18mm the maximum aperture will be f/3.5 and at 250mm it will be f/6.3. As you move from 18 to 250mm, the aperture will change to f/4, 4.5, 5.6 depending on the focal length until you reach f/6.3 at 250mm.

So when you see a lens with just one f-number, it means its aperture it's constant at any focal length (if its a zoom/telephoto lens), when you see a lens with 2 f-numbers, the first means the maximum aperture for the shortest focal length, and the second means the maximum aperture at the longest focal length.

If your photography requires you to work with low light most of the time, a lens with a constant aperture may be better for you than a variable one. The downside of these lenses are their size, weight and price. They tend to be big, heavy and expensive. Third party lens makers however also offer constant aperture lenses at more affordable prices and lighter too.

On the other hand, if what you need are lenses you can carry around, a variable aperture lens is the way to go. You will need to play with shutter speed and ISO to keep the exposure as needed to compensate for aperture changes with focal length.

Focusing motors: Higher grade lenses have focusing motors built into them, unlike normal lenses that depend on the camera's focusing motor located at the mount.

The advantage of these motors is that they make focusing a lot faster and silent.

These motors have all sorts of names depending on the lens maker. In the Sony/Minolta lens range this motor is called SSM which stands for Super Sonic Motor. This motor works at ultrasonic vibrations and makes focusing a lot more precise.

Example: The Sony 70-300 f/4.5-5-6 G SSM is a lens that carries this motor.

Usually this motor is found in high grade lenses, which makes the lens expensive.

Third party lens makers also use this kind of ultra sonic motors, but name them differently. An example is Sigma's H(yper)S(onic)M(otor). Carl Zeiss also uses the SSM motor in their lenses for the Alpha mount.

Higher grade lenses: In the Alpha system, there are lenses that have better quality over the rest of the lenses that are compatible with this mount. By better quality I mean better glass that reduces chromatic aberrations, distortion, have SSM, have more options to customize the lens (like a focus holder button or focus range limiter). Minolta used the G letter to identify these lenses from the rest, and Sony kept it.

Whenever you see a Sony/Minolta lens with a G on it like the Sony 70-300 f/4.5-5-6 G SSM, it means its the best quality you can find in a lens made by Sony/Minolta.

There are also lenses made by Carl Zeiss. These lenses are also high grade lenses, the build quality, glass and coatings used are of top quality as well. They also use SSM.

All Carl Zeiss lenses for the Alpha mount have the ZA designation in the body. Ziess makes lenses for other camera manufacturers as well, but the ones for the Alpha mount are labeled as ZA. The most demanded lens from Zeiss is the Vario Sonnar T* 24-70mm SSM f/2.8 ZA.

That is a zoom lens with a 24-70mm focal range and constant f/2.8 aperture. Uses SSM and has digital coatings (T* designation), the Vario Sonnar designation means its a big lens and the ZA means its a Zeiss lens made for the Alpha mount.

The Carl Zeiss lenses and the G series lenses are the top of the line for the Alpha DSLR system.

Lenses designed for APS-C sensors: Due to the difference in size sensors, image cropping, focal length multiplier issues, etc. manufacturers faced the need to develop lenses that covered the APS-C sized sensor in order to create the desired effect the lens should create, such as wide angle view or effective zoom range for that sensor. A 20mm wide angle lens for full frame is 30mm in APS-C, and the wide angle effect is not visible as it should be.

These specially APS-C size lenses carry the DT designation in order to prevent them from being confused with full frame lenses.

DT stands for Digital Technology. Even though full frame sensors are now available for DSLRs, in the beginning of the digital age, most DSLR makers used the APS-C size and it became a standard size. All lenses that carry the DT designation are only to be used in APS-C sensors. You can use them in full frame, but vignetting will be created.

Lenses like the DT 11-18mm f/4.5-5.6, DT 18-70mm f//3.5-5.6, DT 18-200mm f/3.5-6.3, and the Vario-Sonnar T* DT 16-80mm f/3.5-4.5 ZA are all made specifically for APS-C sensors.

Tamron designates its APS-C size lenses as Di-II, Sigma labels them as DC. Carl Zeiss also uses the DT denomination.

If you need a wide angle lens or a fisheye lens and you use a camera with an APS-C sensor, make sure you look for the DT designation in Sony lenses or the equivalent for third party makers in order to get the effective focal length you need, otherwise you will end up with a different focal length due to cropping.

Type of coatings: A lens focuses light rays in a single point, making it a filter between light and the sensor.

When light hits a lens, it creates all sorts of aberrations, such as chromatic (when subjects have colors they don't have in reality), flare (when light is diffused across the lens surface and make streaks of light appear all over the photo) or ghosting (when a virtual image is formed separate or overlapping the real subject), etc.

In order to address these issues, coatings are applied to lenses. If you grab a lens and look at the front element, you will see there are colors on it, those are the coatings.

Some makers like to label the lens to display the type of coating used on it. Zeiss for example marks their lenses with a T* denomination. There are a lot of denominations for digital coatings and they vary from maker to maker.

The coatings also protect the front lens element, since its the piece of glass exposed to the environment.

The quality of coatings or amount of them used on a lens varies depending on the quality of the lens. Usually higher grade lenses have better coatings than the normal lenses.

Lens kind denomination: Usually a lens doesn't mark if its a telephoto, wide angle, zoom, etc. But sometimes lens makers do mark the lens with the kind it is.

Examples like the 50mm f/2.8 Macro, 135mm f/2.8 Smooth Transition Focus (STF), 500mm f/8 Reflex are example of lenses that carry their kind printed into them. This works to distinguish them from other lenses with similar focal lengths. This way you wont confuse the 50mm f/2.8 Macro with the 50mm f/1.4.

In the case of the 500mm f/8 Reflex, the marking is necessary for two reasons: this lens is not made like all the lenses are, this uses a mirror as part of its elements, which makes it a kind of small telescope and it creates a donut shape of the stuff not in focus, second is because there are other 500mm lenses available, but not constructed like this one, so the marking Reflex helps to differentiate this one from other lenses with 500mm focal lengths.

It's worth mentioning that the Sony/Minolta 500mm f/8 Reflex is the first and only reflex lens to autofocus in the world.

Brief term glossary

SSM: SuperSonicMotor, focusing ultra sonic motor found in G and ZA series lenses.

G: G lens Series, professional high grade lenses.

DT: Digital Technology, denomination to indicate lenses designed especifically for APS-C sensors.

ZA: Zeiss Alpha, Carl Zeiss lenses made for the Alpha mount.

End of Part 2.