What many of you seem to be forgetting in the latest edition of this thread is that A-DEP mode is basically provided for use with zoom lenses, on which it is virtually impossible to incorporate DoF scales.
Also it is clear that others don't really understand why or how A-DEP does what it does. The DoF at a given aperture changes with focal length, so it needs to be recalculated for each zoom setting. That's what the camera's processor does in A-DEP mode. It is a means of accurately ensuring the correct point of focus and aperture when a specific depth of field range is required. The reason Canon don't provide a "shift" capability is that it would basically defeat the entire purpose that the mode is meant to be used for. There may sometimes be a need for more DoF (smaller CoC) but almost never for less (larger CoC). I think the suggestion of a CF to select a preferred Circle of Confusion is an excellent one as long as 0.035mm is used as the starting point and the range were say 0.025mm & 0.017mm. That would probably keep everyone happy. And the argument that it wouldn't get used enough doesn't hold water as you can say that about most CFs. That's why they are programmable CFs and not finger operated controls. I'd almost be willing to bet that this is how Canon will implement this function in their bodies when there is sufficient consumer demand. My 20c worth (up from 2c due to inflation). Norman * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
