Does anyone know why my Lightroom might take so long to export photos as part of a timelapse? I have about 500 RAW files (around 22mb each) and after making edits and trying to export as JPEGs it takes 3+ hours. I found a way of exporting as a timelapse video and that takes even longer. My laptop has 8gb ram and works fine with InDesign and Photoshop
It can depend a lot on what types of edits were made to the images. Obviously if more edits are made, the time to process each frame will be longer. But not so obviously, certain edits are more processor intensive and can require more time, like noise reduction, Shadows, Highlights, Clarity, lens correction, and multiple local adjustments. We sometimes don't notice extra rendering time when editing one image, but when multiplied by 500 images the extra time required per frame can add up to a much longer total export time.
The input and output resolutions also matter. Starting out with 22 megapixel raw files probably does add to the processing time compared to cameras that save fewer megapixels, and a 4K time-lapse export takes a lot more time than a 2K (1080P) export. And the level of JPEG quality will also affect total rendering time. When I use LR Timelapse I often run a faster test at a lower resolution and quality setting before doing the time-consuming final export.
You might run a 50-frame test export with very simple adjustments (e.g. White Balance, Exposure, Contrast), and compare that export time to the same 50 frames with the full set of adjustments you normally apply, and see if you can get a sense of what causes the very long rendering time. If there isn't much difference, maybe it's the JPEG export quality setting.