I have a card on which I shot three different time-lapses.
Is there any way to only process some of the frames from the DCIM folde?

e.g. I have a card with 200 frames, but I only want to process frames 1-50, as frames 51-200 are a different time lapse. I don't want to delete frames 51-200.

Do I have to copy the whole 30GB card to a new folder, then delete the unwanted frames?

Thanks,
Tom

No, just import into one folder, then select the sub sequence and right click in LRTimelapse, then "New folder from selection". This is how you quickly split imports into different folders.