Dust Bunnies Be Gone!
Cleaning Your Digital SLR's Sensor

When using film, each frame was captured on a fresh, clean surface, which was then replaced with another as the film advanced. Digital SLRs, however, have their sensor at the same place that film used to reside. It never moves. Over time, it can easily become contaminated with dust. Lots of dust. These sensors are electrically charged, so every time you change lenses, dust is drawn to their surface.

First, let me say that you should check your owner's manual for information on cleaning the sensor. Some cameras say "send it in to the manufacturer" which is a great way for them to make money, and tie up your camera for weeks per year. But the squeamish should follow that advice.  

That said, I've cleaned my own sensors dozens of times, as have many thousands of other photographers, with great results, and no problems. How do they do it? There are a couple of ways to do it, and at least one way not to. Don't EVER use canned air on your sensor. That's a sure way to get residue on it, and perhaps permanently damage it. 

Many photographers use a method that requires a spatula-like device covered with a PecPad (non-abrasive wipe), or special swabs, onto which a drop of specialized cleaning solution is added. The wetted pad is then gently stroked across the sensor. Although it sounds scary, it really is very, very simple to do. I’ve found the wet technique to work extremely well when dust bunnies are aliens -- Klingons -- and are stuck to the surface. 

The second method is a dry technique using a brush. The fibers of these brushes are exceptionally fine and soft, and you simply "charge" the brush with a burst of canned air, then stroke the sensor. The dust clings to the brush. It is about as simple as it can get, and very effective. Most of the time, the dry method is all you’ll need. 

Two companies offer the above products. The wet method was pioneered by www.copperhillimages.com, although they now offer dry brushes. The dry method was pioneered by www.visibledust.com, who now offers the wet method too. Seems both companies came to the same conclusion most photographers have – dry is best most of the time, but sometimes a little fluid is needed to remove stubborn specks. 

The latest generation of digital SLRs have incorporated their own dust cleaning systems. My experience with the Canon version is that it works surprisingly well, reducing the need to manually clean the sensor tremendously. That said, both a sensor brush and sensor wet swabs are in my camera bag for those times when nothing else will do.

Better Online Photos

When posting photos to your Web site, make sure they are in the sRGB color space. While most pro photographers will probably either shoot their photos in, or convert to, an aRGB (Adobe RGB), for best results for submission or printing, aRGB colors don't look particularly good on the average monitor, which is designed to display sRGB colors. In other words, they tend to look a bit washed out.

An on-line friend of mine recently sent me a link to a very useful website that allows you to plug in your camera model and lens focal length so that you can calculate the depth of field you can expect to achieve.

Why is this important? If you are trying to photograph moving objects, whether they are race cars or birds in flight, the number of feet (front to back) that will be in focus can be the difference between a good, sharp image, and one that you'll toss. If you're in the market for a new lens, and trying to decide which focal length to purchase, you also might find the information quite useful.

All you need to do is select your camera model, the lens focal length (i.e, a 400 mm lens), the aperture you shoot at (f/5.6) and the distance to the subject (I selected 100 feet just as a test), and the calculator will provide you with your depth of field. In the above case, you might be interested to know that only subjects between 98 feet and 102.1 feet will be sharp! That's a mere 4 feet of depth of field.

Here's a link to the DOF calculator. There's a lot of other useful information at this website, called DOF Master.

My thanks to Bruce Rentfrow for sending me the link to this useful site.

Camouflage that BIG WHITE Canon 500mm f/4 Lens Without Tape, and on the Cheap!

You could spend a hundred bucks and buy a nice neoprene cover for your 500, or you could get some camo tape, and slap it on, but if you don't feel like parting with a that much money, and you don't want to get your lens all sticky with tape residue, you might find this of interest.

When my 500 showed up at the door, and I unpacked it, my wife said "holy cow, that thing is as big as your leg." And a light bulb went off, so to speak.

Because over in the corner near the door were my leg gaiters. I took one look at them and knew I was onto something.

Now those of you who don't live where the snow gets deep may not know what gaiters are, so I'll explain. They are fabric leggings that fit tightly around the top of your boots, are fitted at the ankle, and cover you up to your knees. They are waterproof, and most have a full length zipper. The whole idea is to keep snow and debris out of your footwear.

Surprisingly, these gaiters fit this lens as if they were made for it. They have an adjustable tie at the top that snugs down perfectly around the front of the lens hood. They have elastic gatherings at the ankle, which also just happens to snug it up around the narrow neck of the lens. And with a full length nylon (no scratching!) zipper, the gator is a breeze to put on, or remove from, the lens. The material is a rugged, but soft and silent, nylon camouflage. If you place the zipper over the "button area" of the lens, you can get at the controls for Image Stablization, focus presets, etc., in a snap. About the only thing you can't do with the gaiter zipped on is easily get at the manual focus ring, but that doesn't normally pose a problem (I think it was 1989 the last time I manually focused on something!).

I purchased my gaiters at a Gander Mountain sporting goods store in my home town. They ran about $20. 

Here's a photo of one of them on the 500. Looks like it was made for it, doesn't it?

I've not tried it on a 400mm f/2.8 or the 600mm f/4, but I suspect it would fit. However, I have used it on a 300mm f/2.8 w/extenders, and while it's a bit baggy (a few rubber bands snugs it down), and a tad long, it works in a pinch. 

One of the advantages of this gaiter, is that you can zip it off when you don't want a camo lens, or want to insure that there's no moisture under your camouflage. Can't do that with tape!

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