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Proper way to shoot footage for 60i to 30p deinterlacing
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I didn’t screw up any math, but you might have misunderstood. I was referring to the question of whether to use 1/30th instead of 1/60th. I stated that 1/60 is the video standard as 1/48th is the film standard. And when I said you might want to use _slower_ to achieve more motion blur, I was referring to the 1/30th in the original question. 1/30th being a slower shutter than 1/60th.
Anyway… what you said. All good stuff. I just used the 1/48 to better relate to video.
When people shoot 24p, is the shutter still 1/60th? That would acct for why it always has that strobey look to me. 1/48th just gives a little more motion blur I guess.
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When people shoot 24p, is the shutter still 1/60th? That would acct for why it always has that strobey look to me. 1/48th just gives a little more motion blur I guess.
When shooting 24p digital, 1/48th sec shutter is almost always used.
It has that strobey look because …. it’s only 24 frames per second. Movie projection has the same issue, only more severe because the entire image (not just changed pixels) goes black between frames. Movie projection came up with a clever solution. I believe, that testing was done to discover the brain’s “flicker threshold”: i.e.. when a light going on/off becomes perceived as always “on”. I think they came up with something like 60 flashes per second. To solve the movie projection issue, they placed a 3 bladed shutter in sync with the movie so each frame would flash 3 times or 72 total flashes per second for a sound film (~16×3 or ~48 flashes/sec for silent –there’s a reason they called movies “flicks”).
60 field video is beyond the flicker threshold for me, but when I see PAL at 50 field/second it flickers to my eye for a while until my brain adapts and I don’t see the flicker anymore. LCD displays don’t flicker at all since each pixel is always lit until changed, but the motion at 24 fps looks a bit jerky, and to me, the motion blur now looks “false”.
I’d like to see the display/shooting standard adapted to a higher FPS rate. Something like 48 or maybe 60 in this digital age…(yes I know, it won’t have the “look of film”…:)
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Exposure & Shutter Speeds
Film style – shutter
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Don’t shoot in 1/30 mode. Probably you will just lose resolution, if you are shooting on a camera that isn’t mean to do 30p properly (if you were of course, you don’t need deinterlacing in the first place); but MAINLY, you will find that all deinterlacers on the market are designed to deal with 60i or 50i footage, interlaced fields, and to try to create an appropriate motion blur as well, from that information. Shooting at 1/30s shutter will screw this up and your deinterlacing won’t work properly.
However, that being said if you are using Final Cut Studio 1 or 2 you have excellent deinterlacing tools in Compressor as well, you could batch process your footage through there, even convert it to 24p. Results will look better than Nattress’ filter (sorry Graeme) and for that matter better than ReVision or Boris, because it’s based on the Shake optical flow code; but if you max out the quality settings it takes a very long time to process.
Lu Nelson
Berlin, Germany -
Problem with optical flow technology is that although often it’s better, the odd time, it gets worse when the visual data confounds the algorithm. This is a problem with all adaptive image processing, and often the more complex the adaption, the bigger the problem. It’s also not just slow, but incredibly slow…..
– http://www.nattress.com – Film Effects and Standards Conversion for FCP
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I don’t think compressor adds 3:2 either, does it? Do you know for certain?
Graeme
– http://www.nattress.com – Film Effects and Standards Conversion for FCP
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[Graeme Nattress] “I don’t think compressor adds 3:2 either, does it?”
Apple does not support the addition of 3:2 pulldown in software, only from 3rd party cards.
a good friend of mine said:
” apple just tosses in a frame where ever they like without any regard to cadence.”gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows -
Well, there you have it…….
Graeme
– http://www.nattress.com – Film Effects and Standards Conversion for FCP
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