Problems opening multiple Canon .CR3 files

[nigelh72856175]

I have no problem at all working with CR3 files in Lightroom Classic, but in Photoshop the situation is different. I can open a single file successfully if I disable the GPU in Camera Raw preferences, and also open a second or third, but if I try to open more files individually, or open a number of them (even only two!) via the script "Load files into stack", Photoshop crashes. This makes focus stacking impossible. I am using the latest versions (Photoshop 25.4.0 Camera Raw 16.1.1.1733) running on a Windows 11 PC with 11813MB of available RAM, of which I am letting Photoshop use 70% as recommended; the images are 6000 x 4000 pixels and the files are about 22MB each.

If I convert the files to DNG format in Lightroom, I can quite happily open 15 of them at a time in Photoshop.

[Bojan Živković]

Your task may require more RAM. Out of 12GB, only 70% or 8.4GB is available. Windows 11 alone can use up to 4-5GB of RAM. To check the RAM usage, open Task Manager, go to Performance, and select Memory. Then, try to open two photos as you described and observe the changes in RAM.

[nigelh72856175]

I'm pretty certain memory isn't the issue. The machine actually has 16GB in total, and when all the images are loaded as DNGs Photoshop uses less than 4.5GB. I tried two other things:

1. On a different PC which has Photoshop Beta (latest version) and the same amount of memory, with or without the GPU enabled, everything worked correctly. This machine has a different GPU (Iris XE 30.0.101.1960) compared to the machine that failed (GeForce RTX 2060 31.0.15.3619).

2. If I select the images in Lightroom Classic, right-click and choose "open as layers in Photoshop", again everything works.

I also believe that I was able to perform the same operation successfully on 12th January with whatever versions were current at the time, but as I have deleted the individual files I used I cannot be absolutely certain that they were in CR3 format, although I think it is very unlikely that I switched to JPG.

[nigelh72856175]

It seems that one of the later Photoshop updates has now fixed this.