For High Speed Recording, 1080/25p or 1080/50p difference ?

[limyweric]

I did a test record of 240fps on both 1080/25p & 1080/50p mode of someone swinging his arms wildly in front of the camera. During playback i could not really tell the difference. Except that 1080/25p seems to have slightly more motion blur effect. I actually thought the difference should be more obvious ?

In post:
1) If i placed the "240fps" 1080/50p footage on a 25p timeline in FCP, does that make my footage 2x slower compared to the following :
a) placed the "240fps 1080/50p footage on a 50p timeline
b) placed a "240fps 1080/25p" footage on a 25p timeline

If my final edit is going to be 1080/50i (client requested), will there be any issues when i mixed the "high speed" footage with other footages from the same camera shot in "1080/50i" ?

Thanks for reading
cheers,
eric

[alisterchapman]

When you shoot with the recording mode at 50p the recording will contain 50 frames per second. If you place the 50p in a 50p timeline the slow motion is not slowed down as much as it would be if you shot using the 25p slow motion mode. You can only shoot at 200fps when the camera is set to PAL area, not 240fps.

In 25p mode shooting at 200fps results in a 8x slow down. Shooting in 50p mode at 200fps results in a 4x slow down.

There should be no problem using 25p footage in an interlace project.