Cropped images in Develop a little bit more unsharp

Report · Oct 02, 2023

I have a new M2 Mac Studio and latest Lightroom Classic. While editing some bird photos, I discovered that the uncropped image in 100% was a little bit sharper than the same image cropped and showing in 100%. The difference is very small - but it is there...

Did some Googling and found out that others had the same issue and disabling GPU resolved it. Seems to resolve with me as well.

Does anyone else experience this? I hope that this don't affect the exported image - just the preview?

Report · Oct 02, 2023

I do see some such effect in Library, but I think that may be related to the available previews being differently made. Maximising the size of standard previews and ensuring 1:1 previews have been generated, seems to be relevant there though that does come at a performance cost. Perhaps Develop is a better context for comparing image sharpness.

I don't see this effect in Develop, nor in Export, regardless of graphics acceleration setting. One of those settings is, though, whether the GPU should be involved in export processing or not. That would need some very careful testing to achieve an unambiguous answer on whether that has any quality effect. I strongly suspect not.

Report · Oct 03, 2023

It is definitely there in Develop mode - but the difference is subtle, and you need to have the right kind of picture to see it.

I am attaching three screenshots of the same picture.

The first one is the original picture shown in 100% view. The second is the same picture that is cropped also in 100% view. The third is the same as the second, but with GPU turned off.

You can see on the head area and tip of feathers that the second picture is a bit less sharp than the first one. The third picture is sharp again.

Without any edits - just 100% view in Develop mode:

Cropped image in 100% view in Develop module:

The same picture as 2) but with GPU turned off:

Report · Oct 04, 2023

for added info - in graphics acceleration settings (I found I needed to change the selection to Custom, to see these extra checkboxes) do you have the box checked for GPU to assist with image processing, perhaps for export also - or, only for getting involved in display?