HUGE psd file when editing on Affinity Photo from Lightroom

[musicfed]

issue with PSD file being too big when using affinity photo w/Lightroom

 

hello guys - I use Affinity Photo (v1) as external editor on Lightroom classic. when I finish editing, I save and have the box ticked for "Enable "save" over imported PSD files" so I can have the psd file back straight to LR.

the issue is that the resulting PSD file I now have in Lightroom is huge. sometimes 100 or 200MB or more (from a jpg of around 10-15MB), even after super light editing.

I am clearly missing something. why would the PSD file be so huge? 

thanks!

[Old Bruce]

5 hours ago, musicfed said:

I am clearly missing something. why would the PSD file be so huge? 

One thing would be the fact that JPEGs are 8 bits per channel and the Affinity Photo file could be 16 or 32 bits per channel. Another thing is that Photo will make a "Snapshot", which is a copy of the Background layer of the JPEG, this will increase the size as well.

[R C-R]

4 hours ago, Old Bruce said:

One thing would be the fact that JPEGs are 8 bits per channel and the Affinity Photo file could be 16 or 32 bits per channel. Another thing is that Photo will make a "Snapshot", which is a copy of the Background layer of the JPEG, this will increase the size as well.

Yet another thing is JPEG's use lossy compression, even at so-called 100% quality, so saving to another format that is not lossy will increase the size as well.