some of us actually live in Europe, where EVERY movie is speeded up from 24 to 25.
The whole (and sole) reason for video being able to be 24 was to deliver 24 for cinema (obsolete, cinema can have any framerate), nowadays to deliver 25 with speed up, 29.97 with pulldown added (interlaced, so not an option for internet, only broadcast / dvd / blu ray)
So, totally forget about interpolation. That is for standards conversion that you do not need.
Why do you want to deliver 24 and ask these questions? Normally people who WANT to deliver 24 know why they want it. (Those who must due to contract obligations might be puzzled.)
Again, 24 is no longer a delivery format, as it serves no other purpose than to be universal to go to 25 or 29.97.
A higher framerate is better, no broadcast over traditional channels is at 24 and 24 in cinema is an option, not a requirement.
And if anyone states ‘it looks filmish’ let him pay the stock and handling fees for 35mm, see if he likes it then.
Shooting 25P for a night scene makes no sense at all, unless you have very old fluorescent light that flickers at 50Hz
(Modern fluorescent lights are high frequency and have no issues.)
If you have shot under such old light you have shot in a dirty factory. (Very well possible, and in that case 25 was a wise descision, but you suggest this was an important carefull well lit scene.)
Bouke
http://www.videotoolshed.com