The Art of Compromise

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Guitarist Michael Raitzyk
If you haven't already gathered from my other posts on the three exposure elements: aperture, shutter speed and ISO, photography is an art of compromise.  You can't always get what you want most without giving up something you want less.  This is a dance we all must learn.  Let me explain the need for compromise with a couple examples.

Bright Light Situations. Suppose you want to get that nice, silky effect on a waterfall on a bright, sunny day mid-afternoon.  The sun is shining directly on the the falls, and it looks so pretty you have to get the picture.  Here's the problem.  On a bright, sunny day, there's so much light that can be impossible to make your ISO slow enough and your aperture small enough to get your shutter speed in the 2-3 sec. range.  If, on top of that you want a narrow depth of field (large aperture), well, you may as well ask for the moon.

This situation forces a compromise--the best solution is to return in the early morning hours before the sun shines on the falls.  But if that's not an option, you can use a filter, called a Neutral Density (ND) filter.  ND filters are simply neutral grey filters that cut down on the amount of light entering the lens.  I have them in three strengths: -1, -2 and -5 stops.  So if your proper exposure is 1/100sec at f/16 and ISO 100 and you add a -5 stop ND filter, your proper exposure will become  1/3 sec at f/16 and ISO 100.  I used this technique to get the photograph of rapids below.

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Rapids in Patapsco State Park, McKeldin Area
Low Light Situations.  Suppose you're walking outside at dusk and you see a deer running through the woods, and you would like to capture him in his environment with lots of depth of field.  It will be nearly impossible to get a fast shutter speed (say 1/500 sec or faster) and a small aperture (like 1/16) under these conditions.  Your only option is to raise your ISO, and even ISO 3200 may not be fast enough to give you the shutter speed you want.

This situation also forces a compromise.  You could opt for a shallow depth of field and shoot the scene at f/2.8 or f/4.  You could also decide to pan your camera while shooting--that is, you can follow the deer with your camera as you shoot, hoping that the deer will be sharp--this will give you "motion blur" in the deer's surroundings.  There's another trick I sometimes use (and it sometimes works).  I intentionally underexpose the image to get a fast shutterspeed and then try to increase the exposure with software.  If you're shooting RAW, you can sometimes get 1-2 stops this way.  You will have a grainier image this way, but it's better than not getting the shot.  I used this technique to get the photo of the Carolina Wren below.  It's not ideal, but I wanted the bird.
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Carolina Wren
The photograph of  Michael Raitzyk above was taken at night, outdoors, under a big tent with stage lighting.  Using a flash would washout the colors of the stage lighting, so that was out of the question.  Using a tripod would help, but tripods don't generally stop guitarists from moving when used properly.  So my only option here was to get a fast shutter speed.  I didn't want to crowd the stage, so I used my 180mm macro lens "wide open" (the largest aperture) at f/3.5 at ISO 1600.  This allowed me to get shutter speeds of around 1/100 sec.  I used a tripod and took lots of photos to get some of them sharp.  If this lens had image stabilization, I probably would have handheld the camera.

This is the art of compromise.   In dim light, you often cannot have wide depth of field and a fast shutter speed.  In bright light, you often cannot have a narrow depth of field and a slow shutter speed.   You must compromise what you want less to get what you want most.  So you must know what you want most, what to give up to get it, and how to compensate for what you gave up with filters, software, and anything else you can pull out of your bag of tricks.

Comments

  1. Scott, thanks for a great article! I had never thought of the other problem: Wanting to leave the shutter open when there's TOO MUCH light. I learn something every day from this site.

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  2. Hey, thank you for the idea to write it. That was fun.

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