Losing picture brightness when going from library to develop

[richardj53849150]

My problem is this: recently, having loaded RAW pictures from my Nikon D750 into the photoshop library, when I go to 'develop' and the picture is being loaded  the image suddenly loses brightness and goes much darker. I can redress this slightly by increasing the exposure level, but this then loses picture quality, so it's not satisfactory. Interestingly this does not happen with jpeg's which I've already edited in the camera. Does anyone know what's the problem and how to fix it? Thanks Gareth

[Per Berntsen]

When Library and Develop don't match, it's usually caused by a defective or incompatible monitor profile.

Do you see a difference both in Fit view and 1:1 view?

Please post two screenshots of the entire Lightroom window with the same image open in Library and Develop.

Make sure that the histogram is visible in both screenshots.

Also please tell us what version of Lightroom you are running, as well as your OS and version.

[D Fosse · Accepted solution]

Yes, I bet this is the monitor profile.

The reason for the difference between modules, and the difference between raw and jpeg, is that two or three very different color space transformations take place. In Develop, what you see is linear ProPhoto converted into monitor profile. In Library, and jpeg in Develop, what you see is Adobe RGB (sRGB) converted into your monitor profile.

The latter is a much simpler conversion. There is very little gamut remapping, and very little tone response curve remapping.

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Another possible scenario is Lightroom 4/5 under Mac OS Sierra. The net effect is the same, but this time the reason is that Mac OS takes over this conversion into the monitor profile, and *something* was changed in Sierra so that this no longer works as it should. However, this is usually seen as black clipping and shadow banding.