Does anyone know if a good depth of field calculator that will run on Windows Mobile 6 or Excel that take into account your cameras crop factor? I can find tons of apps and Excel files but seem to come up empty trying to locate an app that considers crop factor in the calculations.
The Help File tells you how to set the "resolution" setting to match your camera's sensor size/resolution, which I understand to account for crop factor.
For not too a large distance you can use any FF calculator for a given focal length, f-number, and distance and then divide, yes, divide, the result by the crop factor. Usually it's a pretty good approximation in a pinch. You might use the http://www.dofmaster.com/dofjs.html to play.
An example - you have a 85 mm lens at f/5.6 and the object at 20 feet.
The DOF for a FF camera is 5.76 feet
The DOF for 40D (x1.6 camera) is 3.61 feet.
The ratio is 1.6