P.O. Box 7017
San Diego, CA 92167-7017
(619) 906-8136

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I invented the thirdstop exposure calculator for students in my classes. I found that asking students to quickly comprehend and memorize the relationships between shutter speed, aperture and ISO settings was an unrealistic expectation. Spending lots of time with beginning students caused me to lose my more advanced students. Conversely, when I moved too quickly past this subject I lost my beginning students. The calculator helps everyone stay at the same pace. Even advanced photographers often need to slow down and envision the image they are trying to capture and consulting the exposure calculator helps them do just that. How many times have you uploaded your pictures just to find that your depth of field was wrong and your image didn’t have the emphasis you were looking for? Or have you ever uploaded the picture to find that you were at 1/100th of a second shutter speed while using a 400mm lens and the image is blurry. We all get in a hurry when shooting and consulting all of your shooting options at a glance with the exposure calculator helps you think things through. The result is better images the first time.

Dave Ness, Owner

View Dave’s photography at


As a photographer, I like to recognize good talent when I see it so I’m pleased to present the following artists:

  • Product Graphics Design by Jennifer Ness Derks,
  • Website Design by Ken Anderson, Blacklabz Design Solutions,
  • Website Programming by Steve Berry,
  • Videography by Tom Antl,