Could you please disconnect the Wacom tablet and check Lightroom performance.
Please share the result with us.
This appears to be a common and well-known problem with brushing.
So let's try an experiment
Delete all the adjustment brushes from one photo, give Lightroom a minute or so to make these changes into its database, shut down Lightroom, restart Lightroom and then see if the slowness disappears on this one photo.
Yes, I've checked - it's caused by brushes - I'deleted them and even without restarting "suddenly" everything works fine. Go back to brushes and it gets terribly slow...
Well, I have a few suggestions
- do the brushing as the absolute last step in your editing process
- do the brushing in Photoshop or Photoshop Elements
Now, I don't speak for Adobe, but it seems to me that this brushing problem (and similar problem with spot healing) pushes the limits of the software technology way beyond what the CPU can handle. In other words, you have reached a limitation of what can be done in Lightroom.
I think there is a reallly simple solution for this: don't render effect when brush overlay mask is shown - we can brush needed areas in this mode without seeing the adjustment effect (as it is behind the overlay....) - what do you say, Adobe?
I want to do brushing in LR to be able to sync other parameters in a set of photos when it's needed (let's not dig deeper - I need it ) Either way thanks for clarification.