Originally posted by Adam
Great idea, but also very much a niche. This could easily be accomplished via a photoshop action with crop mode disabled for DA lenses.
Adam, the main problem with what you are proposing is that the exposure will get somewhat random, especially that 4 corners plus two bands on either side of the image will be black (that's ~30% of your image). If you shoot in crop mode, choosing your crop type (regular APS-C, portrait APS-C, or Square as I proposed) before you release the shutter, it would give you many benefits including the following:
- The camera will know exactly what part of the sensor to care about in terms of exposure, but also data processing (think time-saving, memory allocation and buffer fill optimization, battery saving, etc).
- Your chances of taking better composed pictures increase because you will have to actually think about your composition properly and will be able to visualize it right off the bat (rather than making it an after-thought process).
- In portrait APS-C crop mode you'll read the info in your viewfinder or on the screen easily since the text will be horizontal
- In portrait APS-C crop mode your flash will illuminate your subject from the direction you want, and will be easier to bounce (especially if it doesn't have a swivel head like the 1st generation AF 360FGZ)
- In square crop mode you'll effectively use 63% more sensor area (20.4^2 instead of 16^2)
- In square crop mode your crop factor will be effectively 1.18 (24/20.4) instead of 1.5 (24/16). Your perspective control will be easier for scenes and subjects that have 1:1 aspect ratios. Your "35mm equivalent" focal length will be much closer to the lens' actual focal length because you'll multiply it by 1.18 instead of 1.5.