Crop Terms - Please Explain

[snerd]

So I see someone post "this is a 100% crop". What does that mean? I know, a silly question, but I do not get it yet. When I crop, I draw the cursor around what I want in the crop. Is 100% just fully half of the image? No, that would be 50%, wouldn't it? Help!

 

[Derrel]

It means a cropped segment, taken from the file when it has been enlarged to its full, 100 percent size. 100 percent crops can be any sized segments...the eyelashes and eyeball and cheek area from a portrait, or the distant mountains from a landscape, or one section of a city skyline...the idea is that the cropped-out segments are used to allow viewers to see the quality (or lack of it) from the "full, 100 percent view" of a file.

On digital images that have been down-sized, image quality flaws and issues are often minimized. At 100% view, the true quality level of a file is pretty apparent. However, displaying, uploading, e-mailingm, and storing something like say, a 13-megabyte 24-megapixel camera's JPEG files is a bit much, so 100% crop segments are naturally a lot handier to use.

 

[Big Mike]

Just to add to what Derrel said.
Another way of saying 100% crop, might be "a (any) crop of a full size (100% zoom) image"

An image, full size from a camera...is likely to be 3000-5000 pixels wide. A typical monitor is just over 1000 pixels wide, so you couldn't see the whole image (at 100%) on the screen...which is why we usually resize the images first. But if we want to show/see the fine detail, we might crop out a small section, that will display on a screen.

 

[snerd]

Ah..... it took a minute, but then it hit me! So a 100% crop is any section of a "full-size" image that is cropped. If I'm viewing my image at 50% size and crop a portion, it would not be correct to say it's a 100% crop. That about right? I don't know why I had a brain fart on this!!

 

[jwbryson1]

Ah..... it took a minute, but then it hit me! So a 100% crop is any section of a "full-size" image that is cropped. If I'm viewing my image at 50% size and crop a portion, it would not be correct to say it's a 100% crop. That about right? I don't know why I had a brain fart on this!!

Correct. If you zoom in on an image to 100% of its full size, and then crop a portion of the full size image, you will have a 100% crop.

 

[sm4him]

Oh. Well. I think *I've* had it wrong all this time, too. I thought it was when you cropped an image and retained the original size. So, say my original out-of-camera image is 4000 px x 3000 px; I thought it was a 100% crop if I cropped that--let's say I take about 1/4 of the photo out--but retain the original size dimensions. So now the cropped version is still sized at 4000 x 3000.

If it's about zooming in to 100% and THEN cropping, I'm not sure I understand that. Would the crop have to NOT retain the size dimensions of the original for that to work?

I'm confused. Anyone got a visual example of how this works?

 

[Overread]

How to make a 100% crop:

1) Do not resize the photo in any way from its original size out of the camera.

2) Use the crop tool on the second of the photo you want to crop - and crop it.

3) Upload the cropped photo without performing any resizing.

As a result you have a photo that is roughly under 1000 pixels on the longest side which retains the display quality of the fullsized photo from the camera. You can then upload this smaller section of the photo which helps cut down on upload amounts and limits as well as meaning that people don't have to open huge files to see the quality at full size.

Note these days larger storage space for free is getting easier for photos, however you still have the display size and the fact that not everyone wants fullsized photos of their work online.



It's a useful tool to display the full sized quality of a photo to show such effects as softness, sharpness, detail retention, banding or any other properties that the user might want to show.

 

[Derrel]

Here is a 100% cropped section out of a D3x capture shot at f/8 with the 70-200 and studio flash.

 

[sm4him]

Okay, I *think* I get it. So, in my example, with a 4000x3000 image, what *I* was doing in step 2 was cropping, but choosing "front image" in Photoshop, so that it would immediately resize the cropped result to be the same dimensions (4000 x 3000) and the same resolution as the original.
Instead, I should clear that, so that the cropped result is a smaller image.

So, with this image:
Uncropped, it is 4928x3264 and looks like this:


But, don't the dimensions of the crop depend then on HOW MUCH I crop? I mean, if I crop it without resizing, I could end up with this:


OR with this:


But they are now all different dimensions, depending on how much of the photo I cropped out. Do I need to resize the results? Or zoom to 100% when viewing the results? I'm feeling like this is WAY simpler than I'm making it and I'm missing something extraordinarily obvious.

 

[Overread]

Yes a 100% crop will have a rather random size depending how much or how little of the photo you choose to crop out. The key part is that you don't (typically) 100% crop to make a photo, but rather to show the technical quality of the lens at that point.

Maybe you do it to show how sharp it is at it sharpest point - or you do it to show how blurred something is - or how weak or strong the noise levels are.



If your example if what you wanted to show was the sharpness of the duck then either version of your crop would work because the duck and sharpness and details are identical.

 

[sm4him]

Yes a 100% crop will have a rather random size depending how much or how little of the photo you choose to crop out. The key part is that you don't (typically) 100% crop to make a photo, but rather to show the technical quality of the lens at that point.

Maybe you do it to show how sharp it is at it sharpest point - or you do it to show how blurred something is - or how weak or strong the noise levels are.



If your example if what you wanted to show was the sharpness of the duck then either version of your crop would work because the duck and sharpness and details are identical.

Okay, I think I got it. Definitely, probably.
I guess I've really never felt the desire to really DO a 100% crop, so I've just never thought too much about how it would work.

Here is a 100% cropped section out of a D3x capture shot at f/8 with the 70-200 and studio flash.

View attachment 53347

When I consider what the original probably looked like, and how relatively sharp and clear that tiny little portion of it is...I get just the tiniest tinge of jealousy for your gear. :lmao:
Your skills would be quite helpful to me, as well.