Lightroom: How to tell if the Lr (standard) previews need to be updated?

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  • Updated 5 years ago
Any of you Lr/database wizards got any idea?

I have a plugin that auto-sets the black and/or white point (on point curve) - it uses histogram computed from extracted previews. Works fine as long as the previews are up to date, but I don't yet have any way of determining if previews are up to date.

Preview database field? Date-time compare?

PS - comparing the preview file times to last edit time doesn't work reliably (e.g. last-edit time sometimes lags substantially, and refers to metadata not just dev changes...).

R
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Rob Cole

  • 4831 Posts
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Posted 5 years ago

  • 1
Photo of Rob Cole

Rob Cole

  • 4831 Posts
  • 382 Reply Likes
Present work-around: pass responsibility to plugin user, thusly:

Present dialog box with instructions.
User can dismiss temporarily to review thumbs and/or loupe display and decide for him/her-self whether all lib previews have been updated, then
Click button to continue...

Not very satisfying, but at least plugin is no longer trying to make a decision when it can't be sure of the answer (now user is being forced to make a decision when he/she will probably not be sure of the answer ;-}).

R