Today’s Question: Since updating to Lightroom Classic 15, Lens Blur, which has always worked well in the past, now stops working after a while. If I clear the cache and reboot it starts working again. Are there any fixes?
Tim’s Quick Answer: I’ve seen several reports of problems with the Lens Blur adjustment with Lightroom Classic 15, so I assume Adobe will provide a fix reasonably soon. Besides clearing the cache, I’ve also seen suggestions that disabling GPU support has helped work around this issue.
More Detail: I haven’t been able to reproduce this issue myself, but I’ve seen a number of reports from users of both Windows and Macintosh indicating that the Lens Blur adjustment isn’t working (or only works intermittently) since the update to Lightroom Classic 15.
There are indications that clearing the cache helps resolve this issue, at least temporarily. To do so, go to the Performance tab of the Preferences dialog in Lightroom Classic and click the Clear Cache button in the Camera Raw Cache Settings section. I recommend restarting Lightroom Classic after clearing the cache and then testing to see if the Lens Blur adjustment is working.
I’ve also seen indications that disabling GPU support can help with this issue. To disable GPU support go to the Performance tab of the Preferences dialog and set the Use Graphics Processor popup to Off. Once Adobe (hopefully soon) provides an update that resolves the issue with the Lens Blur filter be sure to go back and set the Use Graphics Processor option to Auto (or Custom) to take advantage of the performance improvement it can provide.
