Whites crushed on render

[Randy Strome]

[QUOTE=Glenn Chan;854698]Ok, step-by-step, here is what I would do.

1- Drop your clips into a 8-bit timeline. (The instructions below won't work for 32-bit.)

2- (Optional) Map the superwhites into legal range.
Add Levels filter
output start = 0.006
output end = 0.920

3-
If rendering to the main concept MPEG2 or MPEG4 encoder:
Do nothing for step 3.

If rendering to WMV (the normal way via file-> render as, not WME):
Apply a second Levels filter. Use the "studio RGB to computer RGB" preset.

4- View those files outside of Vegas. e.g. View any WMV files in Windows Media Player.

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Hi Glenn,

That is not what I am experiencing. Speaking only for the EX1 files, if I start as you say, with 8 bit Studio RGB and the clip originally had superwhites, do not adjust levels, and convert without Computer RGB conversion, superwhites will clip.

The same is true if I hand Mainconcept 8 bit computer RGB or 32 Bit. It will blow the superwhites, unless they are leveled down beforehand.

The easy workaround for me is to edit in 8 bit Computer or 32 bit and be sure to hand off no superwhites.

As I noted above. If I take a file in 8 bit studio, 8 bit computer or 32 bit and hand them to Mainconcept with *no* other adjustments, the end product is the same.

[Glenn Chan]

Originally Posted by Sami Sanpakkila

I took the MXF file to Vegas 8bit timeline.
I added levels effect and added Comp RGB to Studio RGB.

I don't believe I recommended this. Re-read the instructions... step 2 would be to add the Levels filter with particular settings.

One question though, why did you point out step 2 is optional? If I dont do the RGB conversion the whites dont look proper after render.

It's not a RGB conversion. It's optional... try it both ways.

If you don't do step 2, then you get standard/normal levels and the superwhites will be clipped. This is the "standard" way of doing things. The clipping happens because the camera is doing something not according to standards.
You can do step 2 to gain additional highlight detail (it compensates for the camera's non-standard behaviour).
Both ways of doing things are correct.

[Glenn Chan]

Randy, I don't know the steps you used (it's not clear to me from reading your post). That could be why we are seeing different things???

In any case, the steps I outlined give the correct results for 8-bit Vegas projects with EX1 (or MPEG2) footage.

[Stuart Campbell]

.......not wanting to cause an argument, but I'm a broadcast cameraman of many years with very limited technical engineering knowledge. I'm new to NLE and have been trying my hardest to learn.

Admittedly, the way Vegas works with colour correction and levels etc etc can be very very confusing (it certainly is to me), but I found Glens articles and advice easy to understand and VERY useful! It's amazing that there is someone out there generous enough to share their knowledge for free! Thanks Glen.

Since I became freelance many years ago it's hard to pester engineers and editors, especially since we all seem to be so much busier than the good ole' days!..

....just throwing that into the mix!

[Glenn Chan]

Thanks Stuart.

[Randy Strome]

Originally Posted by Glenn Chan

Randy, I don't know the steps you used (it's not clear to me from reading your post). That could be why we are seeing different things???

In any case, the steps I outlined give the correct results for 8-bit Vegas projects with EX1 (or MPEG2) footage.

Hi Glenn,

I am actually doing nothing other than setting properties for each of the 3 options, adding a clip to the timeline, and rendering using Mainconcept. The only exception is with studio to computer, where I am applying the stock FX to the clip. I get the same results in each case.

Best, Randy

[Glenn Chan]

Randy, I simply don't see what you're seeing.

Adding a Levels FX to a clip with either the "studio RGB to computer RGB" or "computer RGB to studio RGB" preset will change image and the resulting rendered file compared to rendering out the clip without any FX. Adding FX will change the look of the rendered file (unless you disable the FX somehow, e.g. via the half-moon icon in the Video preview window).

So I think you're drawing erroneous conclusions from your testing or doing it the wrong way (e.g. unintentionally disabling your FX).

[Randy Strome]

Originally Posted by Glenn Chan

Randy, I simply don't see what you're seeing.

Adding a Levels FX to a clip with either the "studio RGB to computer RGB" or "computer RGB to studio RGB" preset will change image and the resulting rendered file compared to rendering out the clip without any FX. Adding FX will change the look of the rendered file (unless you disable the FX somehow, e.g. via the half-moon icon in the Video preview window).

So I think you're drawing erroneous conclusions from your testing or doing it the wrong way (e.g. unintentionally disabling your FX).

Hi Glenn,
It is less the 32 bit and 8 bit computer RGB that interested me. It was Studio RGB passed off to Mainconcept. The first two render as they look in Vegas, which is expected. Studio RGB, however, looks dramatically different in Vegas (as it should), but renders to look the same as the other two with Mainconcept. There is really no FX to disable in Studio or 32 bit, as I am not applying any. This is very intersting if we are getting such a different result. You are testing with EX1 files?

Thanks,
Randy

[Glenn Chan]

Randy, I don't think I understand what your steps are.

Studio RGB, however, looks dramatically different in Vegas (as it should), but renders to look the same as the other two with Mainconcept.

What are you referring to here when you say "studio RGB"?

What is the clip?
What effects are applied to it?
What are the project settings and compositing gamma?

And what are you referring to when you say "computer RGB"?

You are testing with EX1 files?

I've tested with a EX1 MXF file I've downloaded.

[Sami Sanpakkila]

Here are some pics from mainconcept mp4's renders.

1. Vegas timeline (8bit project, no FX)
2. no FX render (Whites clip very hard)
3. Glenn suggested levels (Whites are slightly whiter and blacks slightly blacker than on the timeline)
4. Computer to Studio RGB with levels FX added (Looks exactly the same as on the Vegas timeline)

Jpegs are done by opening mp4's in photoshop and saving as jpegs. Vegas timeline is a screen crab.

Please take a look at the pics and tell me your opinion. I think this is a very interesting topic and Im very close to understanding the procedure and hopefully making amazing videos that look the way I want :)

Again thank you for all your help!

Sami

PS. If anyone wants I can provide this EX1 MXF file for testing.

[Randy Strome]

Originally Posted by Sami Sanpakkila

Here are some pics from mainconcept mp4's renders.

Hi Sami,

My guess is that the confusion is being caused by the way Vegas opens your clips in 8 bit by default. That is what confused me, as this is not the way the clip actually "is". You may notice that Clip browser displays your clip much diffferently than Vegas 8 bit (exactly like your Mainconcept render of 8 bit). So does Sony Clip Viewer on a larger scale. To make Vegas match clip viewer or clip browser (or Edius by default) you have to either convert from studio RGB to Computer RGB or open in 32 bit. Working with the default does not give an accurate represntaion of the original file.

[Randy Strome]

Originally Posted by Glenn Chan

I've tested with a EX1 MXF file I've downloaded.

Thanks Glen,
Answers below:

What is the clip?

-Any EX1 Clip

What effects are applied to it?

-When testing in 8 bit Studio RGB (which is what I call the default 8 bit RGB), no effects applied.

-When testing 32 bit, no effects applied.

-When testing 8 bit computer RGB, the Studio to Computer RGB FX is applied.

What are the project settings and compositing gamma?

-Various for resolution, Both 8 and 32 bit as above for each test.

And what are you referring to when you say "computer RGB"?

-That is what I am calling "8 bit computer RGB"; which is the default 8 bit RGB after the Studio to Computer RGB FX has been applied.

[Glenn Chan]

-When testing in 8 bit Studio RGB (which is what I call the default 8 bit RGB), no effects applied.

-When testing 8 bit computer RGB, the Studio to Computer RGB FX is applied.

These two should look different. When you add the FX to the clip and change the preset, you should see a difference in the video preview window (unless you have FX preview disabled, which will affect rendering).

[Randy Strome]

Originally Posted by Glenn Chan

These two should look different. When you add the FX to the clip and change the preset, you should see a difference in the video preview window (unless you have FX preview disabled, which will affect rendering).

Hi Glenn,

8 bit (Studio) RGB does look different than 8 bit (Computer) once the Studio to Computer conversion has been performed in Vegas. They render to look the same, though, with Mainconcept.

8 bit computer and 32 bit look the same.

Also, selecting the clip in the explorer tab of Vegas and hitting the space bar (playing the unaltered clip as Vegas sees it) is different than in Clip browser, Clip viewer, or Edius (try it). Vegas is doing something I do not understand to EX1 clips.

Thanks for your consideration,
Randy

[Sami Sanpakkila]

This is what Im seeing when I look at the MXF files in Vegas and the original mp4 wrapped file in the Clip browser.

Clip browser: Image OK
Vegas explorer (no matter if project is 8 or 32bit): Image looks washed out
Vegas timeline 8bit: Image looks washed out
Vegas 8bit with Studio to Computer RGB: Image OK
Vegas timeline 32bit: Image OK