Earlier today I was editing some photos, then noticed there was a new version of ACR. I hadn't updated in about a month, don't know what my previous version was. I installed new versions of ACR, LR, and Photoshop. My workflow right now is not to use LR at all, but instead to find my raw files on my computer using bridge, and then use "Open in Camera Raw" to edit my photos.
After the latest update, I immediately noticed that all of my photos are WAYYYYY too yellow when they open up in ACR. They are significantly more yellow than the preview files I see in Bridge, which look exactly how I edited them. By adjusting white balance to be more blue I can make them look correct, so I think the issue is ONLY with white balance and not any other settings. This is only for previously edited files. When I open up an unedited file in ACR, it looks exactly like the preview photo in Bridge.
Another curious thing when I was messing around trying to figure out the bug: When I changed the camera profile to something different, then change it back to it's original setting, the white balance changes.
Example for clarity--- Let's say, before I updated, I edited a photo and gave it a value of 4000k in white balance. After updating I open up the file and it LOOKS as if I gave it a value of 5000k, way more yellow. If I change the camera profile and then change it back, let's say from "vivid" to "standard" and then back to "vivid", it LOOKS like a value of about 4500k. The actual value of 4000k never changes, things just look more or less yellow. You can tell this by using the 'P' hotkey after changing camera profiles and then reverting to the original profile. If the only action is to change camera profiles and then change back to the original profile, you should see no difference when pressing the 'P' key. Or alternately, by pressing undo twice.
I have no idea if this is happening with other cameras' raw files or not. I've only used ACR with the EOS R.
This sounds like it's related to the well-known bug with camera profiles in Lightroom "Edit in > Photoshop".
Camera profiles received a major overhaul a little while back, with some new profiles, and, most importantly, a brand new default profile. This sounds like the problem - it's opening with the right settings, but the wrong camera profile. In other words, it's not opening with the profile used when the image was last processed, but with the new default profile.
The Lightroom issue happened when there was a version mismatch between Lr and ACR. Maybe something similar here.
ACR is definitely opening a camera profile that does not exist in the drop down menu. The drop down menu will show "color" or "vivid" or whatever I originally chose, but when I switch to a different profile and then switch back to "color" or "vivid" (or whatever the original profile was), it looks way different AND the white balance changes.
I did just notice that there are some new profiles from the last time I updated, which was about a month or so ago. "v2" versions of some of the profiles. Definitely seems to be a bug with those. But there's also a white balance bug which I think is separate.