C. Byrne
November 10th, 2005, 01:25 PM
When you capture footage from a BetaSP deck, is it 8 bit or 10 bit uncompressed?
View Full Version : BetaSP capture 8 or 10 bit? C. Byrne November 10th, 2005, 01:25 PM When you capture footage from a BetaSP deck, is it 8 bit or 10 bit uncompressed? Zach Mull November 10th, 2005, 02:38 PM If your capture hardware supports both then you get to decide - one of the joys of analog. I think most people capture in 8-bit because 10-bit takes up more disk space, and currently it's only useful for effects because no one delivers content in 10-bit. Graeme Nattress November 10th, 2005, 03:22 PM I think you'll find that a lot of people do deliver in 10bit though - that's DigiBeta for you. However, 10bit is way too good for BetaSP, and 8bit uncompressed is also way too good for it, although it will preserve the quality you started with. If your card has the option PhotoJPEG75% is a very good codec to use as it takes up little disc space and is more than visually lossless. Graeme Zach Mull November 10th, 2005, 07:02 PM Oh, I meant deliver as in DVD, broadcast, cable, satellite, etc. Or do end users actually watch 10-bit content if it's broadcast from DigiBeta? I thought that in actual delivery it's all 8-bit. Graeme Nattress November 10th, 2005, 07:14 PM You deliver it to the broadcaster on 10bit digibeta - who know what happens after that :-) I think some stations dub your Digibeta to VHS before compression to MPEG2 before broadcasting :-) Graeme Gary Chavez November 18th, 2005, 11:00 AM Dear Graeme, I'm having this argument right now with a producer here. We are corporate video department. My mission is to create and distribute VNRs (video news releases) His mission is a streaming in house LAN network video production. He wants to capture 8 bit simply to free up RAID space. (which has not been a problem so far) I have always captured 10 bit to keep the quality at or near BETASP levels, because I then reconvert to analog and deliver BETASP. I do this because my video goes straight to the 5 local affiliates and must match their on-air look seamlessly. So far the video has matched perfectly. Is 10 bit overkill? Graeme Nattress November 18th, 2005, 02:44 PM 10bit is overkill for BetaSP. 8bit uncompressed is overkill IMHO. You can get practically perfect quality with PhotoJPEG codec at 75% or other such compressed online quality codec. Going down to DV is going too far as that's compressed a little too much. I don't think you'd ever see a difference between 8bit and 10bit capture. Only way you'd see an improvement is mastering to DigiBeta instead of BetaSP. Graeme Glenn Chan November 18th, 2005, 11:13 PM It's kind of hard to see 8 bits of resolution. Take a look at http://www.glennchan.info/video/FCP/tonal-test-original.png In the boxes at the very left, the inner box is just one RGB value higher than the outer box. If the box were smaller, it'd become really really hard to see it. 2- However, don't draw the conclusion that 7 bit is as good as 8 bit (or than 8 bit is as good as 9 bit). - Some LCDs are 6-bit and can't reproduce the image properly. - Bit depth is related to gamma, which is different between computer and video, and different between different displays. - Your display can't hit the full dynamic range of your eye. - For acquisition, higher bit depth can make sense if trying to capture high dynamic range. |