Strange issue in viewport with 4.15.1

Hello everyone,
I don’t know what the correct section of the forum to post this is, so I ended up in here, because in some way it’s related to rendering.

Well, the images are self-explanatory (in attachments). This projects is ported from 4.14.3 to 4.15.1. When creating a new default map, I get this sh*tty illumination problem but only in the viewport and only while not in PIE.
As soon as I press the play button, all shows as it should. But then again when I stop the PIE again that hard-to-see map returns.

Is this some kind of bug? I tried in a clean project directly created from 4.15.1 and it works correctly.

Check this setting:

@IronicParadox Thank you very much! That was the problem. Dunno why it was at “Fixed at Log +4 = Brightness 16x” by default lol. Set it at automatic and it’s now solved.

You’re welcome!