Photographing your art work isn’t hard and the digital world makes it easier. 

This is part two of three, on shooting your art work: why photo editing.

You don’t need to understand why your pictures don’t match your art or your daughter’s birthday party.  But we think it’s helpful to have a sense of why because most of us think that when our pictures aren’t what we expect we have done something wrong.  Maybe not, maybe it’s your camera—and if you don’t want to be Richard Avedon or Ansel Adams—solving these problems won’t be hard.   

Some point-and-shoot digital cameras do a great job, some expensive cameras do a poor job.      

Photographers can spend thousands of dollars on lens, not just to see further (length), or to work in less than perfect light (faster), but also to be sharp. 

Here’s a problem: you want to focus an image onto a plane surface (the sensor or film), you or your camera focuses: but each color that makes up what you see has a different wave length so ideally focuses at a slightly different length (lens to film).  You have one lens, one sensor and somehow you expect all colors to be focused at the same time in the same place—nice and sharp.

And if your lens is a zoom lens, you’ll want it to be sharp at every length and every f-stop. 

Not all lenses are created equal.  Even within a given brand and product line, some lenses will be better than others.  That’s one reason why your camera may do a better job than mine, even if we have the same brand. 

(Specific lenses often have known distortion characteristics.  There is software that can correct various distortions for specific lenses.) 

Most companies test their high-end lenses, one by one, against a given lens that is the standard they must meet or exceed. 

All of this is why good lenses cost more.

Most digital cameras come with some sort of editing software.  This is not just a dry darkroom where you can perform all sorts of photo magic, it can be important in many basic ways.

Your camera softens every image it takes—no matter how well you focus or how good your camera and lens are.  Camera shake adds to the problem.  I have seen many people hold their cameras out so they can see the monitor as they frame the picture: which is more steady, holding the camera against your head to look through the viewer or holding it 20” out so you can see the monitor?  There was a rule in the film days (not point and shoot cameras): use a tripod if the length of the lens was a number higher than the number  (denominator) of the shutter speed (a 300mm lens could be handheld at speeds faster than 1/300 second, 1/600 for example; a 180mm lens should be tripod mounted if shooting at speeds slower than 1/180 second, 1/60 second for example).  Most cameras have built-in photo-editing software that at a minimum sharpens and adjusts the color cast, brightness, and contrast.  Sometimes this is invisible, sometimes you have a menu and can select various options. 

An image file that has not been edited inside your camera is called RAW.  Most manufacturers have their own standards for raw files, and usually you can’t save your images as raw files until you get well above the average point-and-shoot camera.  Most cameras, however, do a decent job of making your images look good.  Sometimes they can be better. 

Our eyes are remarkable.  We adjust for color shifts (from early morning cool to late afternoon warm, from yellow incandescent to greenish fluorescent), we see detail between similar colors and we see colors as different depending on the surrounding colors (For fun: see webexhibits.org, go to Color Vision & Art, see colorcube.com go to illusions, or go to library.thinkquest.org/27066/theeye/nlindex.html).  Our cameras don’t see that way, but that is what we expect from our photographs—what we see or what we remember we saw. 

Our digital camera brains make the adjustments their designers think we will want.

Then, to make image matters worse, most cameras compress the image files, usually in JPEG format, which is a universally accepted image compression file format.  Every time you save (not close) a JPEG file, it deteriorates because decompressing tries to fill in the blanks, then it is compressed when you save, creating more “blank” places that will be filled in when you open it again.  As a rule, when you open a jpeg save it as a TIFF or other lossless format.  Opening and closing is okay, opening and saving is not.  How much your image might deteriorate depends on the subject matter, the amount of noise (grain), the amount of compression, etc. 

Finally, all photography compresses the luminance range of what you’re shooting.  A good photographer tries to put into the print contrast, sharpness, color in controlled ways that create the illusion of the full luminance range of what was seen.  The human eye is remarkable.  It can see an object in direct sunlight with luminance level of 100,000 lx and at night (no moonlight) at 0.0003 lx.  Without use of any specific unit of measure, let’s say a landscape up by the Grand Canyon at noon could have a luminance range of 10,000, from the brightest object to the darkest shadow.  Film can reproduce a range of 200, and photographic paper a range of 100. 

To see a very concise, well illustrated, explanation of lens problems and terms see photozone.de/3Technology/lenstec3.htm

After we have a good set up for our camera and art work (see part 1), we have to be concerned with:
Sharpness
Color matching
Luminance matching
Noise
Distortion

Don’t panic.  Most digital cameras make it easy to solve many of these problems in the camera and the rest, if you need to, can be solved in your photo-editing software.

To read our other guides click Guides