For many years now, I've noticed that cameras of different sorts and image editing program display a preview image of different colors from the final image, while it's loading the final image. I've noticed this on several different models of android phones, as the photo app was loading the image I had taken; I've also noticed this on the LCD screen on DSLR cameras, including Pentax and Nikon models, and also in Lightroom, which the the main desktop photo editing program I use.
After all this time, it's bugged me-- why is this so? Usually the preview images appears to have "better" or more saturated colors-- it seems to be the "human-friendly" version that phones deliver to consumers who want good-looking images over color accuracy.
Here are some screenshots from Lightroom CC. Notice that the first image, you'll see the
loading... text pop-up over the image, and at a glance, the image seems to skew bluer. The second screenshot has the image completely loaded, and it doesn't have as much blue as the preview loading image.
These are freshly imported NEF images from my Nikon, so I don't suspect any sort of jpeg progressive rendering.
What is going on here?