Ok, this one has bugged me for a while now. Originally I though it was some sort of limitation of my old PC but after upgrading to a new machine with an i7 proc, 32gb ram, etc. etc. that should easily handle Lightroom tasks, it still occurs. I've tried to search the internet to find an answer but it either only happens to me or I'm not using the right keywords to search. Anyway, let me try to explain what happens...
Let's say I am in Library and I want to read the Metadata for 200 photos (playing with LRTimelapse). When I choose to read the metadata, it seems to work fine but only on the images that are displayed on my screen. Let's say I can see 30 thumbnails in grid view, the changes only occur to those images unless I scroll down. So, for me to get all of the changes applied, I have to scroll down a bit, wait for the changes to affect what's on the grid, scroll down a bit more, wait, rinse and repeat until they are all done.
This also happens in the filmstrip if say I'm in the Develop module and want to Sync some settings or do a copy/paste of the develop settings. I have to scroll through all of the images in the strip to make sure the changes are applied to every image.
So, is this a normal behavior? Whenever I watch videos of other people doing editing, it doesn't seem to affect them.
Thanks in advance for any help.
So, for me to get all of the changes applied, I have to scroll down a bit, wait for the changes to affect what's on the grid, scroll down a bit more, wait, rinse and repeat until they are all done.
The changes are applied to all the selected photos immediately. But LR sometimes delays the regeneration of the previews and thumbnails until you scroll to make the thumbnails visible. But whether or not you scroll, the changes have been made, and you don't have to worry about it. You can force all previews and thumbnails to be built by selecting all the photos and doing Library > Previews > Build Standard-Sized Previews.
(There is one exception to this, a bug acknowledge by Adobe, when you apply Auto Tone to a batch of photos. In that case, you must force all the thumbnails to be visible for the changes to take effect.)