Say I have a photo with a 4:3 aspect ratio that is 18 MP, and I simply want to get rid of dead space on the lower third of the image. Which of the following would be the most used method for this?
I struggle with this, because if I were to process a large amount of photos using the first technique (which I do already use fairly frequently for hobby shots) as to send them to a client, wouldn't it be annoying for said client if every image had a different and perhaps non-standard aspect ratio?
Say, thereby, that you'd only crop utilising standard ratios (3:2, 4:3, 2:1, 16:9 ...); would it be acceptable to mix all of them when delivering, or rather have a limited amount of used aspect ratios?
Say, thereby, that you'd only stick to cropping in 4:3 (or, by extent, 3:4 for vertical shots); would it bother a client if the resolution on all photos were inconsistent? In case it would, then the third method seems best, although it guarantees a loss in quality (of which I'm not quite sure how drastic the effect would be, as I'm guessing it works better with small resizes on high-MP images than large resizes on low-MP images) ...
Thanks in advance!
What aspect ratio you should use when cropping depends on how you will use the final image.
Personally, I use 3:2 because that is what my camera produces and it matches the most common print size available to me. If I crop it to a different aspect ratio but decide to print to 3:2, I would have to crop even further which ruins the composition.