what the heck is "overcrank"?
I have had numerous users post use the word "overcrank" when it comes to sony's phu60k or the SHDC memory card option....Can someone please define to me what in the world is "overcrank"....Thanks
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overcrank - my posts when someone says they're not using ClipBrowser with CRC on.
It's a film term dating back to when cameras were hand cranked. The cranking the camera faster (or slower) would change the film playback in the projector which was at 16fps (or 24fps depending on the time period referred to). Set EX to 720p24 p25 p30 and use S&Q and set to a faster frame rate which results in slower playback. Of course one can learn this and many other things when using Google. Slow motion - Wikipedia, the free encyclopedia |
Craig you must be an "oldie" like me.
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Simply put, the intent of overcrank is to get the slow motion look. It is effectively done by increasing the frame rate.
A typical scenario would be to double the frame rate. So if you are in North America shooting at 29.97 (30) frames a second you would set your EX camera to 60 frames using S&Q mode at 720/60. The big caveat that some people don't know or forget is that to get effective frame rate increases on the EX you have to be shooting in 720 and not 1080. You can "apparently" shoot up to 42 frames of overcrank on the SDHC cards but most (read almost all) people use genuine SxS cards for "slomo" work. It's not worth the risk of dropping frames. The Sony hardisk recorder has the same bandwidth limitations as the SDHC cards so I would avoid using that as well for slomo shooting. |
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It doesn't say anything about not using the Mac Finder to copy the whole folder. Is there a technical rationale against using the Finder to copy the whole folder? |
OMG!! You just woke up a ticking time bomb. (wait to Craig reads this!) hehehehe
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ClipBrowser uses CRC which verifies the copy. ShotPut does this too. The rationale is that you don't want to have to pay for the re-shoot or lose the client due to a corrupted master file. As I heard yet another Sony rep say, entirely unprovoked by anyone even asking the question. "NEVER drag and drop folders or files. Use ClipBrowser!" I have a hunch he was sick and tired of the support phone calls asking how to rescue a corrupted master clip. |
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The technical rationale is CRC. ClipBrowser and ShotPut do file verification.
Generally if you want to decrease the risk of technical problems you use ClipBrowser. A corrupt file is a technical problem. http://en.wikipedia.org/wiki/Cyclic_redundancy_check Quote:
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Why does overcrank 60 fps use up to 80 Mbs when 720/60p use 35 Mbps?
Does overcrank give a better image, frame by frame, or what? |
It's probably about 87.5Mbps at 24/60fps.
Playback will then be approximately 35mbps at the flagged playback rate. Quote:
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A good analogy would be building a house - if it costs £x to build a house, it will cost far less than 2x£x in building costs to build another of twice floor area. Overcrank is different - the end playback is 25fps, which should be at 35Mbs. Record 50frames in a second, and you have to record at 70Mbs to give the correct data rates for playback. |
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