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wendell westfall
02-22-2008, 10:29 PM
I'm confused about how to refer to how much an image (as it came out of the camera) has been cropped in post processing. Specifically, how would I refer to an image from which I had removed 25% of the total image before posting? I would say "a 25% crop", But I see references to a 100% crop . . . what is that? Is there a generally accepted terminology for cropped images? Hope I've made my question clear.

Wendell

LeeOtsubo
02-22-2008, 11:40 PM
Hi Wendell,
First, the easy one. A 100% crop is a crop out of an image at 100% used to closely examine focus accuracy without posting the entire image. For example, if your image is 3000 pixels x 2000 pixels (6 megapixels) and you wanted to examine one eye for focus accuracy, you view the image on your screen at 100% and crop out a small section covering just the eye. At 100%, each pixel in the image is equal to a pixel on the screen. Hope I'm making sense.

As for standard terminology re: cropping, I've always referred to remainder. IOW, if I cropped out 25% of the image (25% is what I want), I referred to that as a 25% crop. If I cropped out 75% (deleted 25%), I called that a 75% crop but I can see where there might be confusion. I'm not sure how others use the terminology.

Alfred Forns
02-23-2008, 06:08 AM
Wendel I can understand your confusion I like Lee's explanation and it is accurate

Estimating the crop is were the confusion sets in I look at it like fishing How big was that kingfish Well about twenty four pounds .... well you place it on a scale and it might not reach eight Same with crops!!!! Actually it is interesting because as in the size of the fish the size of the crop is evident Normally the dof is a dead give away !!!

Jim Poor
02-23-2008, 09:55 AM
You could go purely mathematically and figure the original pixel dimensions and then the percentage of the same after the crop.
I pretty much just eyeball it though.
I pretty much try to say "about xx% of the frame shown" because I know some people use % remaining, while others use % taken away when they say "this is an XX% crop."

wendell westfall
02-23-2008, 11:33 AM
Thanks, guys. I have been using the terminology exactly opposite from the way you're describing and recommending. I am happily amending my ways.

LeeOtsubo
02-23-2008, 11:45 AM
BTW, 100% crops are typically used by pixel peepers trying to find some minute flaw, real or imagined, in a lens. This is often done to have something to blame for one's photographic and/or photoshop shortcomings. :D