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I noticed that (on my slow laptop) when I first open a newly imported RAW file in Lightroom the first view of the photo (non-thumb view, while the loading spinner is still there) is noticeably different with more vibrant colours and brightness than when Lightroom finishes processing it and the loading spinner disappears. Loading the RAW subsequently results in the latter being displayed.
It's a bit difficult to explain so here are some screenshots. This is what I see when I first open a newly imported RAW while Lightroom is "loading":
This is what I see after Lightroom has finished loading the file less a few seconds later:
What exactly is happening here? Also, it seems to me that Lightroom must be applying some default settings when opening RAWs, can those be changed/viewed etc?