I sometimes work with time lapses, but they’re all only a small fraction of the number of frames you’re working with!
If I was in your situation I would first try just letting Import run, but if not much changes overnight then try importing smaller chunks.
I do know that the Import dialog box is slow. Even just loading embedded previews from directly attached storage is much slower than viewing the same images after import, so I’m not surprised that it’s taking forever to load 400,000 embedded previews from a single folder over a network, even as fast as the connection might be.
Still, it’s worth making sure the preview options are being set for the right reasons…
In short:
- The Camera Raw cache only speeds up loading into the Develop module.
- Previews speed viewing in all modules except Develop.
Following Adobe's guidelines for performance optimization, I've alredy set my Raw cache to 150GB in anticipation.
By @boondock
Nothing wrong with that on paper, but that size might not be necessary. In the article “Debunking Myths,” The Lightroom Queen found that most people only need a much smaller Camera Raw cache size. See Myth #3 in the article linked above.
To be clear, the Camera Raw cache only affects the Develop module, when re-loading images recently viewed/edited in the Develop module. If I understand it correctly, if your goal is to speed up general viewing in any module except Develop, the Camera Raw cache will have no effect because it affects only the Develop module, the only module where full camera raw data is loaded.
A Camera Raw cache size of 150GB could make sense and speed editing if you expect to frequently switch among large numbers of your 400,000 images while staying in the Develop module. However, if you are going to edit the time lapse by applying edits to relatively few keyframes and have the edits interpolated to all other frames (such as when using software like LRTimelapse), then you might only be loading a few of the frames into Develop and wouldn’t need a 150GB Camera Raw cache.
I've also disabled automatic XMP write and intend to render full 1:1 previews to make the edit process easier.
By @boondock
Rendering 400,000 1:1 previews will take a long time and a great deal of storage space. It will take a lot less time if you make sure GPU acceleration is enabled for preview generation, like dj_paige said. The previews will be stored in the catalog folder, in the file with the name editing in …previews.lrdata . For 400,000 files I expect a 1:1 previews cache to be a few hundred GB, depending on the frame size in pixels.
Rendering 1:1 previews will not “make the edit process easier” (if by “edit” you mean in the Develop module) because they’re the opposite of the Camera Raw cache: Previews apply in all modules except Develop. 1:1 previews only make one thing easier, and that’s reviewing images with all details fully rendered. Which is valuable to those trying to quickly cull images by focus accuracy.
In other words, if you want to view the images…
…as quickly as possible after importing, Embedded & Sidecar previews are the best. But they’re limited to the resolution and quality settings set in camera for generating previews for raw files, so they might or might not be 1:1.
…using the current default Develop settings in Lightroom Classic but don’t need to see fine details/check focus, then Standard previews are good. They’ll fit the screen but may save time by not rendering every last image pixel to full 1:1.
…at full 1:1 so you can check focus of every image, then you want the method that takes the longest and creates the largest preview cache file, which is to generate 1:1 previews.
I don’t take the time to generate 1:1 previews immediately after import because the images aren’t edited yet, I don’t want to waste time generating previews that will be immediately invalidated with the first Lightroom Classic edit. Images appear quickly enough in Develop on my computer that if I want to see full detail for some images, I just open them in Develop and zoom in.
For time lapses, I don’t build 1:1 previews until after I sync my first Develop edit pass to all images. The reason I think it’s worth taking the time to generate 1:1 previews at that stage is it’s the first time I want to see all frames after applying Lightroom Classic edits. After the previews are done, I can hold down the right arrow key in Loupe view to do a rough preview of the time lapse.