Stinky-Dinkins said:

Yeah, by 24 I mean 23.976.

If you're working with all (LD, DVD, and broadcast) interlaced sources meant to refresh at 60hz, converting everything to 25p and then to 24p in the final stages, how exactly does this work? Is it able to take the two halves of the interlaced image at every 1/60th of a second and combine the data to make one solid frame? Wouldn't that leave you with it running at 30p?

Are frames dropped?

Frames themselves aren't dropped, but fields are. It's called inverse telecining.

Usually, there are 2 interlaced fields for each progressive frame at 30fps (29.97). But, when 24fps film is converted (telecined) to 30fps, extra fields are added to preserve timing. These are invisible to the naked eye. So, instead of a field pattern of 2:2:2:2:etc., we get a pattern of 3:2:3:2:etc.

Inverse telecining is literally removing those duplicate fields which restores the 2:2 pattern and results in a speed of 23.976fps.