Working out time remapping vs. real time...

Hi all,

Just a quick question relating to a feature in AE. I'm about to shoot some stuff in slow motion and was wondering if there was a way (something like a mathematical equation, or a nice converting site or something!) to work out the relation of the fps to the real time...

For example, I am filming at 4000fps. and editing at 25fps - I want something to happen in the slow motion that occurs 30secs into the 25 frames edit. Now obviously when filming this I need to work out at what point (i.e. how many seconds I've been filming) that this will happen (probably one or two seconds in I presume)... Is there a way to do this without messing around with the time-remap function and work out the timing so I can do it in-camera (with the aid of a stopwatch?!). I thought I'd ask here as I'm sure some of you will have come across this before with playback at higher fps counts then shooting etc.

Hopefully that was clear enough!