#8. "RE: As I recall, Bill Claff's numbers indicate..." In response to In response to 7
Cape Coral, US
>It is the other way around. The cropped image has less DOF >than the uncropped image (at same f-stop, same focal length, >same subject distance). If you want to maintain a given DOF, >then you will need to stop down the aperture, which usually >means higher ISO (if you want to maintain you shutter speed), >so less DOF for the cropped image.
Well... no. At least not unless I misunderstand your point.
For a given FIELD OF VIEW a cropped sensor on the same f-stop and focal length will have a different DOF than an FX sensor.
But if it's the same distance, f-stop, focal length, the actual in-focus area is the same whether the light falls on the cropped portion of the sensor or the whole sensor. Just think about it in post processing -- if you crop you don't change DOF, you just change field of view.