Why does my Lightroom preview change after loading?

Question

Everybody who is using Lightroom probably has seen this:

You have imported RAW files. Lightroom shows a preview, but contrast and color of the preview change after a few short seconds to a slightly different view.

For some users the change is small, for others the change is huge: colors are different (read: wrong), contrast is off.

Rumor says this is happening only (more?) for Nikon users.

What is Lightroom doing here?

I'd guess as first preview LR is showing the JPG preview file, which is embedded in the RAW file, then LR renders the RAW file itself and is showing it's own interpretation.

But why is this interpretation so different to the embedded JPG?

Answer

You're right in your conclusion that Lightroom is initially showing you the embedded jpeg. However, Adobe isn't privy to how the camera manufacturers process their jpegs in-camera, so Lightroom is never going to be able to produce thumbnails/previews/images that match the jpegs SOOC.

I'd suggest that the main issue is whether you are happy with your ability to use Lightroom to produce images in post-processing that you are happy with. If you are, then I (along with countless others) don't think it really matters whether Lightroom's interpretation is the same as the jpegs that came out of the camera.

In other words, there is no "right" or "correct" image from your camera, just whether or not you find the results visually pleasing.

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