For a time-lapse, the frames need to be in true capture order before assembly. If your camera restarts numbering in each folder/card, filenames alone may not sort correctly when you combine everything.

Best approach:

1. Put all images into one folder.
2. Sort them by capture date/time (EXIF “date taken”), not just filename.
3. Batch-rename them into a single sequential series so the filenames match shooting order.

Many photo apps can do this: sort by date taken, then rename as 0001, 0002, 0003, etc. That makes Time Lapse Assembler read them in the right sequence.

Also check your camera’s file naming settings. If numbering resets for each folder, switching to continuous numbering can help avoid this in future shoots.

If you used two cameras rather than two cards, make sure the cameras’ internal clocks were synchronized before shooting; otherwise “date taken” may not reflect the real order between bodies.