View Full Version : Question - In 32-bit mode, black levels don't appear correct on DVD


James Binder
August 25th, 2008, 03:13 PM
Here's my project settings:

NTSC DV 24p widescreen
Pixel format: 32 bit
Gamma: 1.000

Footage:

.mxf files (From Sony EX1)
35 mb/s
1920X1080

Output: (DVD)

MainConcept MPEG-2 (DVD Architect 24p NTSC Widescreen video stream)

When I compare the DVD (via a DVD player) to the original footage (within Vegas 8) on the same monitor, the footage looks as if the black levels have been raised (on the DVD). I've read many threads on the subject here and am thoroughly confused. Glenn's article is wonderful, but I'm not sure that I understand all of the jargon.

In my 32 bit mode project, I've used lots of color correction and levels adjustment throughout. I've experimented with the studio RGB to computer RGB, but not sure when and where I should apply.

If I import the mpeg2 file back into Vegas and bring into a 8 bit project -- the blacks are clearly raised compared to the 32 bit project. If I switch to 32 bit mode all appears right again (with the mpeg2 file). However the DVD appears (on other television sets) to have the appearance of the mpeg2 file in an 8 bit project -- with the black levels raised.

Can somebody tell me in plain language what I need to do so that the black levels appear the same on the DVD as they do within my Vegas 8 project?

Thanks in advance --

Jeff Harper
August 25th, 2008, 07:04 PM
James, have you tried playing it on a television yet?

James Binder
August 25th, 2008, 09:20 PM
Jeff --

Yes it looks the same on a TV. The black levels are still off -- actually, it appears that the luma is being raised altogether, which of course is affecting the black levels as well.

Again, I think the issue is because I'm using .mxf files which do something weird in 32 bit mode when rendered. If anybody can set me straight here, I'd appreciate it.

Jeff Harper
August 26th, 2008, 02:06 AM
Sorry James, I did not read your post thoroughly...I see now you had watched it on televisions....

Rob Wood
August 26th, 2008, 08:08 AM
From what I'm reading I think your MXF is decoding to computer RGB levels... in that case I'd suggest putting a Computer RGB to Studio RGB filter on the Video Output FX track just before rendering to MPEG-2 to draw everything back into range.

Caveat: I'm not sure about this; I still get mixed up regarding 32bit / codecs / colorspace in Vegas with HDV formats.

Note: I referenced DSE's Vegas8 book and noticed he had a couple solutions on the topic, one of which is to nest your 32-bit 1.0 gamma project into a 32bit 2.222 gamma project.

Bill Ravens
August 26th, 2008, 08:28 AM
James...

I've been around and around on this issue until I finally gave up. Glenn tried to explain it to me but I still don't get what's happening, myself. I think the best workaround, at this point in time, is to do what was suggested by Rob Wood...drop a Computer to Studio RGB filter on the timeline. If that doesn't work, reverse the filter. And, DON"T pay attention to what you see on the Vegas Preview Window...it's not right.

Jeff Harper
August 26th, 2008, 08:32 AM
Not that this will help at this point James, but referring to Bill's reference to Vegas preview window, I am so glad I finally broke down and bought a broadcast monitor...I get a much better idea of the end result without having to render, burn, and test on televisions.

Paul Kepen
September 23rd, 2008, 01:46 PM
From what I'm reading I think your MXF is decoding to computer RGB levels... in that case I'd suggest putting a Computer RGB to Studio RGB filter on the Video Output FX track just before rendering to MPEG-2 to draw everything back into range.

Caveat: I'm not sure about this; I still get mixed up regarding 32bit / codecs / colorspace in Vegas with HDV formats.

Note: I referenced DSE's Vegas8 book and noticed he had a couple solutions on the topic, one of which is to nest your 32-bit 1.0 gamma project into a 32bit 2.222 gamma project.

I am having a similar (but almost the opposite) problems with V8. When I use the standard 8bit mode, the resultant rendered files are over all too dark, but the highlights are 'blown out." I've been trying the 32bit mode. This seems to solve the dark image, but bright sunny highlights are still blown out. The same file rendered with Premiere Pro 1.5 looks slightly richer and no overblown highlights. Previously I used Vegas 6 and I did not have this problem. Someone said there are many references to this problem here, but I have not found the specific solution. I was hoping that by upgrading to V 8.0C that Sony would have fixed this, but no such luck. My Project settings are : Pixel Format: 32 bit floating point, Compositing Gamma 1.00 (linear).
Also, I've looked, but in my Vegas 8 Video Plugin Chooses (FX), I do not see any "Computer RGB to Studio RGB" plugins. How do I get that? Thanks for the help. Sincerely - PK

Mike Kujbida
September 23rd, 2008, 03:14 PM
Also, I've looked, but in my Vegas 8 Video Plugin Chooses (FX), I do not see any "Computer RGB to Studio RGB" plugins. How do I get that? Thanks for the help. Sincerely - PK

It's a dropdown template in the Secondary Color Corrector.

Paul Kepen
September 23rd, 2008, 04:40 PM
It's a dropdown template in the Secondary Color Corrector.

Thanks for the Info Mike :)

Mike Kujbida
September 23rd, 2008, 07:41 PM
I know that James said tell me in plain language but, if you want some explanations in not-so-plain language, check out the 32 floating bit (http://www.dvinfo.net//conf/showthread.php?t=112738) and 32bit float vs 8 bit (http://www.dvinfo.net/conf/what-happens-vegas/102508-32bit-float-vs-8-bit.html) threads.
Make sure you have some aspirin (or a good stiff drink) available for the way they'll make your head ache :-)

p.s.you're welcome Paul

Bill Ravens
September 23rd, 2008, 07:54 PM
In Vegas' 32 bit FP mode, all signals input in YUV will be converted to broadcast RGB standards. All RGB signals input will be left unchanged. So, if you have a YUV signal in which black is RGB 16, black will be automatically raised to RGB 32.

The "fix" is as was mentioned above. Apply a broadcast to computer RGB correction.

Paul Kepen
September 23rd, 2008, 10:00 PM
I know that James said tell me in plain language but, if you want some explanations in not-so-plain language, check out the 32 floating bit (http://www.dvinfo.net//conf/showthread.php?t=112738) and 32bit float vs 8 bit (http://www.dvinfo.net/conf/what-happens-vegas/102508-32bit-float-vs-8-bit.html) threads.
Make sure you have some aspirin (or a good stiff drink) available for the way they'll make your head ache :-)

p.s.you're welcome Paul

Thanks Mike, I will have to check these threads out tomorrow - bed time now. I still don't really comprehend why this was never a problem with V6, nor is it with PremierePro which is 10 bit. Yes, I know that V8 has 32 bit, but my initial problem was rendering HDV at 8 bit with V8. I capture to Cineform Prospect with Premiere (My original Cineform purchase was a bundle with PPro). From there I open the CFHD.avi files with Vegas - my preferred NLE. However, I am not happy that my projects in Vegas 8 (8 bit or 32 bit) don't render out with a normal tonal range. Hopefully these little tricks will solve my problems. Again, I really do appreciate the help.
Have a goodnight - Paul

Steven Thomas
September 26th, 2008, 07:56 AM
All I can say is good luck Paul.

As much as I like using Vegas, as you found out, it's really messed up with these colorspace/levels issues. I am blown away Sony has done NOTHING to fix this.

Paul Kepen
September 26th, 2008, 11:58 AM
All I can say is good luck Paul.

As much as I like using Vegas, as you found out, it's really messed up with these colorspace/levels issues. I am blown away Sony has done NOTHING to fix this.

I couldn't agree with you more Steve. I am seriously considering upgrading my 3 year old Adobe Suite and dumping Vegas. I never upgraded my PPro 1.5 because it worked, and because after I learned Vegas, I preferred it and have stuck with it. However the faster workflow with Vegas is more then negated by the difficulty of this color space issue. I waste more time rendering and burning coasters by far. Hence, I'm now beginning to think that the Adobe package would be far, far less time consuming overall.
If just using the Computer RGB to Studio RGB pluggin on the timeline FX worked, I'd say fine. However, it seems to dim the overblown highlights but still does not return the detail in those blown out highlights. Also, this pluggin makes clips that don't have bright sunny highlights too dark. When I render those same clips with my 3 year old PPro 1.5, the detail is still there in those same highlights. I am using the latest Vegas 8.0 c. There is a Vegas 8.1, but that is for Vista 64bit, I am still on Win XP pro, hence I've stuck with the 32 bit version. As you say, its unbeleivable that Sony has not addressed this - its more important then there effort to push out a 64bit version. By the way, does anyone know if the same issue is in the 64 bit version? I would assume it it the same.

Steven Thomas
September 26th, 2008, 10:22 PM
If just using the Computer RGB to Studio RGB pluggin on the timeline FX worked, I'd say fine. However, it seems to dim the overblown highlights but still does not return the detail in those blown out highlights.


I'm seeing the same thing.

Thomas Barthle Jr.
September 28th, 2008, 04:47 PM
Open a new project with 32 bit setting and 2.222. Open or nest your project you are having problems with in this project. Apply a "computer to studio" plugin to that video track. Apparently, the computer to studio preset does not work properly in 1.000 linear light processing, but you can open a 1.000 project inside a 2.222 project without affecting all your fx settings. This is long story short from Glenn Chan's site.

Paul Kepen
September 30th, 2008, 09:53 PM
Open a new project with 32 bit setting and 2.222. Open or nest your project you are having problems with in this project. Apply a "computer to studio" plugin to that video track. Apparently, the computer to studio preset does not work properly in 1.000 linear light processing, but you can open a 1.000 project inside a 2.222 project without affecting all your fx settings. This is long story short from Glenn Chan's site.

Thanks Thomas. It still seems like a lot of hoops to have to jump through, increasing the time spent on a project and more chances to get something goofed up and haing to spend hours trying to sort it out. This needs to be fixed by Sony Software ASAP, or a lot of us loyal users will be defecting to brand "A".

Thomas Barthle Jr.
October 1st, 2008, 05:33 PM
It would be nice if someone could write a script that will automatically render the timeline twice: once in studio RGB (for broadcast) and computer RGB (for computer distribution).

Edward Troxel
October 2nd, 2008, 07:28 AM
It would be nice if someone could write a script that will automatically render the timeline twice: once in studio RGB (for broadcast) and computer RGB (for computer distribution).

That would be fairly trivial to do. There's several free renderers out there and it wouldn't take much to tell it to render twice instead of once adding an effect to the project in-between the renders. In fact, I wouldn't doubt that the Veggie Toolkit could already do that.

Paul Kepen
October 6th, 2008, 05:34 PM
For What it is worth, I was able to get a very good looking BluRay disc from this project by going back to my original 8bit edited version. I used the Computer to Studio RGB filter (in Sony Levels). I was not happy with the default settings but I found that by adjusting the low slider from the 63 setting down to around 30-35 and leaving the high slider at 922, it looked very good. (I am out of town right now, so sorry I'm not more specific with the slider names). I originally tried 32 bit because my 8 bit encodes were very dark with burnt out highlights. 32 bit mode did not fix the burnt out highlight issue, but shadows were too light with washed out mid range color. After spending way too much time horsing around with the computer-studio RGB filter, broadcast colors, etc, and the fact that 32 bit took 20 hours to encode vs 3 hours for my 30 minute project, I decided to go back and try 8bit. Until I get a faster computer, and have a lot of time to experiment with 32 bit, I think I'm going to just be happy that I've got 8 bit working. The footage I was using was outdoor bright mid day sun. Shots included Ocean surf on a rocky shoreline, and some darker shots in the woods. The camera was a Canon HV-20.

Graham Bernard
October 6th, 2008, 11:11 PM
For What it is worth, I was able to get a very good looking BluRay disc from this project by going back to my original 8bit edited version. I used the Computer to Studio RGB filter (in Sony Levels). I was not happy with the default settings but I found that by adjusting the low slider from the 63 setting down to around 30-35 and leaving the high slider at 922, it looked very good.

I hear you!!! Good feedback.

The footage I was using was outdoor bright mid day sun. Shots included Ocean surf on a rocky shoreline, and some darker shots in the woods. The camera was a Canon HV-20.

Well, maybe herein lies the "initial" issue. Surf and Midday Sun, in my way of thinking, will produce a narrow dynamic to start adjusting. Everything is up there in the "clipping" regions already - high contrast and with "narrow" dark shadows and masses of reflections glinting away. But I could be very very wrong. So maybe you going back to the original and starting off again, would be getting you the best digital source anyway? Yeah?

Grazie

Paul Kepen
October 7th, 2008, 12:26 AM
Hi Graham.
Yes the lighting was not ideal. We were on a quick trip and I didn't have the option of waiting for the sun to get lower in the sky. Watching the clips straight out of the camcorder to the HDTV, the quality was substantially better. I rendered these same clips with Adobe Premier Pro for a comparison; the results were excellent without any filtering. I've been using Vegas 6 for the last 2-3 years without problems, even with high contrast water and mid-day scene's.
I love Vegas, and have no desire to go back to PPro, but I don't like having to waste so much time tweaking. The suggestion of nesting a 32 bit linear file into a new 32 bit 2.20 gamma file would probably be the way to go. I needed to be done with this, and my almost 3 year old computer takes too long with 32 bit encoding. Yes I hate the gradient banding issue, but they are quite in-frequent overall (none in this 30 min project). So, until I get a new computer, this will do for me. I'm just happy that the studio RGB filter made it simple to fix. Take Care - PK