Slow motion?

HBlack

HBlack

Underage Member
How should I go about getting the slowest, cleanest slow motion possible? I'm shooting on an HVR-V1U, which has 24p, 30p and 60i. Which frame rate should I shoot at, and what should I do with it once it's brought into after effects? The frame rate of the final project is going to be 24p. I've found slowing down in premiere uses frame blending, which is undesirable. I think I'm supposed to separate fields in 60i and reduce the frame rate, but I'm not sure how to go about doing this.

Also, when I'm shooting 24p and I bring it into the premiere project some frames are doubled and it's at 30fps. How should I go about fixing this? I downloaded the canon 24f preset from adobe and it won't open/work.
 
If you have AE7+ then you can use the Pixlemotion frame blending meathod and timewarp to make frame accurate slow motion. just make sure you have a shutter that is over 1/120
 
I'm somewhat unsure of that. Are the results acceptable? Premiere does something similar in that it blends frames, but that tends to look like crap.
 
both AE and PPRO CS3 have a feature called time remapping that can use pixel motion frame interpolation to basically do the same thing that twixtor does. the results are terrific as long as you use the correct settings. basically you just turn your frame blending option to pixel motion, and then use the time remapping feature to slow things down or speed them up as desired. the program will analize each frame, and make independent intermediate frame based on pixel motion analasys. again. the results are phenominal as long as your settings are correct and your using the features properly.
 
I'll give it a try. What do you mean by settings are correct? Just a high shutter speed and proper exposure, or is there anything else to consider?

Also, when using pixel motion what frame rate should I shoot at?
 
shooting interlaced probably won't help you very much in the long run. I'd rent a higher framerate capable camera like the HVX to do any slow motion shots. Shooting at 60 frames per second can yield some pretty good results when you slow it down even further in post since the differences between the 60p frames are less significant and thus interpolation is more accurate over a longer stretch. Did that make sense?
 
I follow, but renting another camera isn't an option. Spending $200 to rent a camera for one shot in a movie with a $300 budget doesn't make sense, so I've got to use what I have.
 
What exactly needs to be in slow motion, and how slow? Frame interpolation from After Effects or even the Twixtor plugin can be very effective given enough resolution in the image.
 
shoot at the highest possible progressive framerate you can without sacrificing the needed resolution. so if you can shoot 30p over 24 then shoot 30. thats a 25% increase in the amount of frames you have to work with as compared to 24p. if you can shoot 60p instead of 24, then you have a 150% increase in frames to work with.

as far as settings when using time remapping, you want to be sure that your using the pixel motion frame interpolation instead of setting your frame blending options to "frame blend" or anything else. pixel motion is the only interpolation method that will actually create new sharply independent frames based off the estimated motion of each pixel between frames. the other methods just mix frames together to create intermediate frames. then you want to slow your footage down by an even factor, like 1/2 speed, or 1/3 speed, or 1/4 or 1/5 ect. you dont want to slow it down to a percentage that gives you something like .3645786 original speed because the motion is generally cleaner when the time factor is divisible into whole frames. and another thing is that when using higher fps footage as "overcranck" to get slow mo at 24p, you need to calculate this based off of your timelines actual 24p frame rate, and NOT the framerate of the footage you are converting. getting 24fps all frame playback out of a higher than timeline framerate clip should be done by stretching that clip out in advance. then you do your actual frame interpolation to slow the clip down beyond the real frames it has running at 24fps. so if you put a 30p clip (thats not already written to play back @ 24fps as slightly overcranked slow mo footage like you can with the HVX) into a 24p timeline, a big mistake that people do when converting other framerates (higher or lower than 24p for overcrank/slow mo or undercrank/fast motion in post) to smoothlly play back 24p is that they calculate the stretch factor of thier non 24p footage based off of the footages frame rate instead of playback @ 24fps. for example... 30 is 125% of 24, but 24 is only 80% of 30. and the difference of 6fps between them is 25% of 24 and 20% of 30. so alot of people would look at the 6 frames they need to drop from 30 and say .. well , 6 is 25% of 24 so i need to slow down my 30p footage to 75% and it should be smooth 24p. but thats incorrect. they need to base it off of 24s relationship to 30 ...not 30s relationship to 24. so if you are in 24fps and you have 30 frames that play back in one second, you need to slow it down by 20% or a fifth of its speed, so that plays back only 80% of its frames in one sec, and the remaining fifth go to the next second. this way you get 24 frames the first sec (which is 80% of 30) and the final fifth (or 6 frames) will start the next second.

anyway im sure i used more words than needed to say whet i needed to and it ended up much too confusing for a discernable read, but basically when your converting framreates for over/undercranck footage, you need to base the calculations off of the actual working timeline framerate relationship to the over/under crank footage framerate, and not the other way around to get smooth playback of each frame @ 24p. so if your timeline is 24p you always ask " 24 is what percentage/fraction of (your over/under crank footage framerate)" and you slow your cranked footage down or speed it up to that percentage for smooth playback. ..then from there you can start frame interpolating ect for additional time/motion based effects.
 
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