I usually shoot in RAW and convert with UFraw plugged in GIMP. Then I
have a choice of extensions to use for saving the file produced. I
presume that if I use .xcf there is no compression and if I use .jpg
there will be some compression. When working on the file I assume it is
best to save as .xcf and not to use .jpg until the picture is finalised.
I would like to know how the contents of the .jpg file so formed compare
with the contents of a .jpg saved directly on the camera.
The reason I ask is because I would like to use PTLens to remove CA but
it seems that the software will only work with .jpg.
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