AZaman

I am also having the issue above, where the astrophotography stack stops working if flat frames are present. It works fine with all other frames I use (lights, darks, biases) in any combination but will fail during the stacking process if I add even 1 flat frame. For reference, I am using compressed lossless RAF format raw files from a Fujifilm X-S10. This fails whether the option for white balance calibration from master flat is ticked or unticked. Unless some part of the raw processing was changed, I'm not sure the raw format or camera is the issue because the astro stacking process worked fully with the initial Photo 1.9 release but stopped working soon after. I think that was when the first update was released and I can confirm the latest update did not fix it.

I also have noticed this problem since I got the Fujifilm X-S10. It's a little surprising considering the sensor and processor are used in several Fujifilm cameras, which are listed as being supported.

I am encountering some problems with the new version of Photo. I have used screenshots of an unbalanced astrophotography image to illustrate my layer merging issues. Almost every time I merge layers, there will be small horizontal artefacts inserted by the operation. They disappear when I go back a step in the history. You can see an example in the pre- and post-merge crops below of the same area. This is only one, there are several that appear per merge. There is also a softening or blurring that occurs when I merge layers as well. In this zoomed out screenshot, you can see the overall effect. Close up, the effect is very subtle and almost unnoticeable but zoomed out, it become very apparent. I am also experiencing the terribly slow performance others have reported. You can see the resource usage in the attached screenshots when the program froze. They are 15 minutes apart and the application closed itself soon after. My PC is a Microsoft Surface Pro 7 with i7-1065G7 CPU with the integrated Intel Iris GPU and 16GB RAM. It is no slouch and fully up-to-date but Photo slows to a crawl and often just closes. I believe this performance hit started a couple of months ago, after my Surface Pro 7 updated to Windows 10 version 20H2, but it was still somewhat usable. With this new update, Photo has become very difficult to use. I have tried all combinations of using GPU/CPU/OpenCL rendering but nothing helps.