Can someone explain the merits of 10 bit in Edius 6?

[John Hooper]

I would like to know when to use the 10 bit HQX codec in Edius 6 when it is available?

I usually edit PAL SD DV and DVCAM footage. Would I use it for this sort of thing?

[dpalomaki]

At least in theory, 10-bit processing results in less quanization (round off) error, and thus a better, smoother image (less banding). I suspect this would be most apparent in highly processed images where the cumulative effects of round-off woud apear

So provide a simple example of round off; consider pixel with an 8-bit value of 15, divided by 2 it becomes 8 (or 7 depending on how you round-off) and if multiplied by 4 later it becomes 32 (or 28). In 10-bit the initial value of 15 is scaled to more like 60, and when divided by 2 = 30, if multiplied by 4 = 120, and when scaled back to 8 bit for transmission it is 30, what you would expect, not 28 or 32.

I've read that for purposes of displays and video-like appliacions the typical human eye can still distinguish bands or steps in a 7-bit gray scale. So 8-bit was used to to get past the banding issue at minimal cost in bits. Storage and processing having been expensive in the early days. If you add 6 dB gain (without interpolation) to an 8-bit digital image you end up with 7 bits of luminance resolution - and potentially visible banding.

For cuts only editing it is probably over kill, but with complex and layered effects it is a good idea.

[John Hooper]

Thank you Don. Not sure I understand all the maths, but I get the general idea.

So would I use the HQX in preference to say the Canopus DV if I was editing DVCAM material?

[Jerry]

You will still see an improvement even with the 8bit effect processing contained within a 10bit project for HD.
I have seen it!
DV, not so much.
If you are capturing to Standard Def uncompressed, you probably will see a difference in quality as opposed to DV.
I do a lot of underwater projects. I have a major issue with gradient levels in relation to darker ocean to lighter ocean. 10bit will improve color detail and the standard transitions do look better than in an 8bit project.
Just by capturing to uncompressed 8bit MJPG, I was able to remove at least 90% of the gradient banding in a lot of the shots. 10bit HQX takes it the rest of the way.

I get the best results with avc-intra 100 10bit 4:2:2 .

[Jerry]

The MJPEG comes from Decklink.

I have already tried these things and they look better in a 10bit project, even with 8bit color correction, than in a strickly 8bit project. These were all tried with avc-intra 100 files. It may not be 10bit with a scope, but when it is displayed on a monitor, it sure looks better to me.

[tingsern]

The most obvious advantage / effect you can see is when you use After Effects to render and then post the results to EDIUS. Currently, too gradual a gradient causes very bad banding when viewed on EDIUS 5. But - not so when previewed on AE. I definitely looked forward to getting EDIUS 6.

[Red Union Films]

Hi John.

Have not used DV for a while but am quite sure it is 4:2:0 8 bit for PAL. If you capture DV it will not make any difference, if you capture to HQ at 8 or 10 bit there will be no difference.

I would always capture HQ for any tape ingest, as the system will work faster with it's own codec. The argument for HQ 10bit with DV, would be to keep your footage either future proof or easier to mix with other formats that are 10 bit. Unless you are going to do over the top destructive effects, it would be hard to see any difference with 8 or 10 bit processing on 8 bit footage.

Any lack of colour resolution (banding) that you may or may not see with 8 bit video, will still be the same recording it at 10 bit. I have used 8 bit HQ on HD-CAM and it looks great, even after being coloured and graded through Da Vinci and Quantel.

Even if you recorded a 4:4:4 10 bit signal at that same resolution, your final output is something to factor into the equation. If your final output is 4:2:0 8 bit, then you may see some aliasing on fine colour gradiants, like filming blues and greens under water.

For most of the time, most people will not tell that the signal is 8 or 10 bit. But for best practice it is always best to record at the best you can.

Hope this helps.

Dave.

[Red Union Films]

Just to let you know- HDCAM destroyes footage much more then Canopus HQ. Avoid it- use HDCAM-SR or send file- it will be probably conveterted to DPX to feed Da Vinci or Quantel anyway.


Andrew

Hi Andrew.

I use both 440 and 880(SR). HDCAM 440 does not destroy footage neither does Canopus HQ. The files do not get converted to DPX, you can do a live feed via SDI output fom EDIUS/THUNDER with VTR emulation for deck control of EDIUS/THUNDER. Your facts are way wrong. My addition to this post was to help John understand if he needed to upgrade from his present system based on SD on DV, to a 10 bit workflow, not to get into one with someone who does not know what he is talking about. I dont much appreciate being pulled on things i have said to help other users, and have quite given up the ghost on being polite to people on this group who's only intention is to try and make others look stupid. You want to flex your brain? pick a group of 5 year olds, otherwise think a little harder before making such an idiot of yourself.

John. Hope you found what I had to say of some use. Bottom line is, if you dont plan on moving from SD on DV any time soon, then your present workflow is a good one. Yes, the extra functions of E6 may be of some use to you, but to do what you are doing at the moment, you would not gain anything with 10 bit and would only spending more money.

Dave.

[Red Union Films]

Hi Andrew.

Just to answer your points.

HDCAM and HDCAM-SR are 2 seperate formats.
If you say HDCAM 440 (880) you mean HDCAM-SR, which is very good quality. Canopus HQ does destroy image but it's marginal and in almost all cases not a problem at all. HDCAM-SR also destroys image.

Never said they where not different. SR uses a number of bitrates, like I said, and from this you can get HDCAM signal from a SR master. HQ does not destroy the image, it uses compression just like most other high end formats. If you think this destroys the image then the industry needs to have a re-think. Maybe Sony should have a re-think about it's mild compression destroying SR masters.

HDCAM is not that good. 8bit only, 1440x1080 (not 1920x1080), 3:1:1 sampling, but it's way cheaper than SR version, so many people use it. I've seen big macroblocking on HDCAM on few tapes already. That's why I said avoid it if you can. Generation is also a big problem with HDCAM.
Converting to DPX does not destroy image, I just mentioned it because most of the grading software like this format.

Dont know when the last time you used a HDCAM, but you must have missed it when Sony went full 1920 with 4:2:2 colour space. Macroblocking? you're having a laugh are you not. Never said converting to DPX destroyed the image. You will find all grading software and hardware accept many formats.

Feeding Quantel with HDCAM is not the best solution (assuming that your source was very good quality and whole editing has been done with uncompressed or HQ files). It looks like you use HDCAM-SR, which is different story.

If you shoot HDCAM, then this is the best format to ingest, process, colour, whatever, seeing as it was the format shot on. Using any codec or RGB to edit with that is above the HDCAM format only serves the edit system it is on. Using SR to master does not make it a different story, it's a submision format.

As I said- 10bit would be much more important for processing than for capture only, even if you work in 8bit project/source . You can't keep 8bit final output with 8bit processing, which is quite visible if you use some filters/effects especially at high settings. Hope to have all filters in Edius 6 working at high enough precission to have real 10bit final output (for some of them 8bit can be enough).

10 bit anything will not make a blind bit of difference to Johns situation as per my original post. Have you worked 8 bit video on 10 bit systems before, then dumped back to whatever 8 bit format it came off, then done the whole process in 8 bit to see what the end result is. There is a small question of colour space as well as bit depth.

Like i said before, you jumped in feet first and tried to discredit what i was saying, while taking Johns thread off topic in the process. You did not even have the common courtesy to try and help with Johns original question. It's a very stupid thing to go head to head with someone who does this stuff for a living, when all you are armed with is what you read. It's like going to a gun fight with a water pistol. All that i have mentioned i do, so my comments are based on real world experience. You start bleating on about what you read on the Thomson report. Try taking footage at the uncompressed RGB 444 level, and go down from there with the variations, ingest the same via HQ 8 bit and Edius uncompressed. Look at all on a grading monitor via the Thunder SDI 422 8 bit output and tell me what you see.

John. Sorry for your post turning into something it was'nt, I am just not the type of person to be called into question by someone who does not posses the knowledge they say they have. Believe me, what you read in tech reports is not always the same as doing it in the real world. Forums have a lot of know it all's who have read everything, and then there are those who actually use and work with stuff they say as their profession.

Anyway, must go, am just finishing of compiling the reels of our latest feature that was shot on HDCAM, digitized into Edius 5 with 8 bit HQ, edited at the 8 bit level, that then went in live into Da Vinci via Thunder, and recorded back to Edius 5 8 bit HQ, and still looks great. 8 bit is dead long live 10 bit.

Cheers.

Dave.

[Red Union Films]

Hi Andrew.

Check out the spec on the F900, it's not 1440 3:1:1 As for your hang up on bit depth in processing low level formats, you are just plain wrong. I have many more years over you in the industry, i think it may count for something. Maybe using your eyes for something other than reading tech reports may help.

Do not reply to me on this thread anymore, it is quite unfair to John and anyone else who was interested in the original post. If you want to carry on, start a new topic in the lounge.

Cheers.

Dave.

[Jim N]

Dave,

I am very pleased by your real-world experience with 8 bit and advice not to be distracted by the tech heads but I do wish you would ramp down on Andrew. Your experience clearly differs and you have explained why and that was enough for me.

Jim

[Red Union Films]

Dave,

I am very pleased by your real-world experience with 8 bit and advice not to be distracted by the tech heads but I do wish you would ramp down on Andrew. Your experience clearly differs and you have explained why and that was enough for me.

Jim

Jim.

Please read the last post, I did say to move to the lounge to carry on. As for ramping it down, I am not one to take stick for no reason and see no reason why Andrew can't just do the honorable thing.

Cheers.

Dave.