Reconstructions with subsets of frames?

Hi, I’m sure this has been discussed before, but I would love to have the capacity to easily calculate reconstructions using subsets of movie frames.

As we get to higher and higher resolution, assessing the effects of site-specific radiation damage will likely become increasingly important (e.g. see here for an example:

To assess such effects, we need to refine using particles generated from the full aligned average, then calculate a reconstruction using particles extracted from the same movies, but only using the early frames. This is currently not possible (or very awkward) in cryoSPARC, but would be very useful to have.