View Full Version : Color changes during preview


Stacy Rothwell
March 22nd, 2007, 03:37 PM
When I use Cineform under PPro 2, and do a preview, the color changes slightly in the program window. It looks nice when it's still but when I play it, the black level rises and it starts looking washed out.

Anyone else having this problem or know of a solution?

Is it an overlay issue?

Thanks,

stacy

David Newman
March 22nd, 2007, 03:53 PM
It is explained in the readme. The many graphic card drivers don't do YUV to RGB conversions correctly. ATI gets it right with the overlay on and wrong with it off, NVidia the other way around, Matrox (who's customers are video professionals) get it right in both modes.

Stacy Rothwell
March 22nd, 2007, 07:36 PM
David,

In the README, it only says what to do with an nvidia card not an ATI card. My laptop has an ATI Mobiliy X700.

Any help is appreciated.

Thanks

David Newman
March 22nd, 2007, 09:34 PM
Read my reply above, it is all related. NVidia was the worse offender, but ATI has messed up also. Try turning the overlay on.

Stacy Rothwell
March 22nd, 2007, 09:39 PM
David,

I'm sorry but I have looked everywhere and cannot see where to turn overlay on in ATI drivers.

Stacy

David Newman
March 22nd, 2007, 11:20 PM
sorry, no, within the Aspect HD playback settings.

Stacy Rothwell
March 23rd, 2007, 12:49 PM
David,

Haven't had a chance to do the change with the ATI card yet, but I followed the instructions in the readme file regarding my desktop with an nvidia card.

All that resulted was that the scrubbed/still image looked more contrasty than normal and when I hit PLAY, that contrasty image did the same thing --- black level rose and color shifted.

I tried it both with USE OVERLAY on and off in the Project/Playback settings.

Any ideas?

Thanks

Stacy

David Newman
March 23rd, 2007, 01:08 PM
You have control over those levels with the NVidia overlay panel, adjust until the picture is to your satisfaction (you can adjust while Premiere is running -- much faster than restarting PPro.) Some gfx cards models are worse than others and more tweaking. Normally NVidia is fine with the overlay off (it is on all our cards.)

Ben Winter
March 24th, 2007, 02:02 PM
Interestingly enough, this happens to me too, but very rarely--often I just need to restart the playback and it corrects itself. This is with a Parhelia APVe. I initially thought of describing it as an increase in contrast but the black level rising is closer to the truth.

Graham Hickling
March 28th, 2007, 02:13 PM
At least on my system (a Nvidia 7600GS card under XP) the advice in Cineform's Readme file hasn't worked since I updated from the 8x Forceware drivers to the 9x drivers.

The 9x drivers introduced a "new look" Control Panel option. The "old look" panel is still there .... but I can't get the overlay settings to function. YMMV.

With the new look Nvidia panel the tweaks you need are under "Video and Television" and then under the "Video color settings". Instead of the default settings being 100, they now seem to be +50 or thereabouts .... so the values of 109, 112 and 101 in the Cineform readme no longer apply.

Douglas Turner
April 4th, 2007, 12:09 AM
So.... which image is correct? The still frame or the footage while being played back?

I have an Nvidia 7800GS, and have a nicely graded frame sitting there infront of me, but when I play the footage, it's suddenly a lot brighter.

Will Cineform will be putting out a new readme for the new Control Panels on the latest NVidia drivers?

I have a Dell 30" LCD and use Colorvision Spyder to calibrate it - so tweaking the hell out of the Nvidia settings seems a bit pointless, as the Spyder should have already sorted my settings out. I just need to fix the discrepancy between the still frame and the playback.

Douglas Turner
April 4th, 2007, 04:01 AM
Have managed to make scrub and playback image almost identical.

First things first, Cineform Playback Settings (Premiere Pro->Project->Project Settings->General->Playback Settings) are set to:

ON - Enable overlay surface
OFF - Deinterlace video while scrubbing (as I want to see combing and then the result of my deinterlacing)
ON - Use HD Colorspace
ON - Use video systems RGB
ON - Disable preview mode playback
max - Memory size

NVIDIA Control Panel - I switched to old view (View->Switch to the Classic).

Color Correction:
Desktop 100 Bright, 100 Contrast, 1 Gamma
Overlay - 109 Brightness, 112 Contrast (as per Cineform Readme!)

Video Overlay Settings:
Saturation - 101

And the scrub and playback image are now as good as identical. Major confusion for me was the 'Enable Overlay Surface' setting above - the description seems slightly wrong - it's the overlay on my main screen, not an external monitor (and the above NVidia Overlay settings only works for me when it's set to ON).

Anyway - if other people are having these problems you could try setting the Enable Overlay Surface, then perform the tweaks suggested in the Aspect Readme.

Cheers, Doug.

Tim Homola
May 3rd, 2007, 02:35 PM
I am having a huge color shift problem when I go to scrub. I have tried the overlay on and off and I still get a huge shift, wat too bright and way too blue. I am not sure if it a color space issue or if my SpyderPro screen calibration is being lost. Any thoughts?

Douglas Turner
May 3rd, 2007, 11:58 PM
Scrubbed for me looks the same as a still frame. The played timeline looks different.

Make sure you're using overlay (set the Cineform Playback Settings for this) - and then open up your NVidia control panel and tweak it - at the same time, scub and play your premiere output.

I'm not sure how the Spyder works with overlay - but basically I try to tweak my NVidia overlay settings so the played footage looks the same as the still shot.

Before I altered my settings, the played footage was appreciably lighter than the still shot.

Tim Homola
May 4th, 2007, 07:07 AM
Douglas, thanks but I have the ATI card. I have tried both overlay in Aspect and in the Control Center software and cannot solve it yet. :(

Tim Homola
May 4th, 2007, 12:27 PM
I uninstalled Aspect and everything works fine now. Hmmmmm.... I would really like to use Aspect but I've got to get this fixed or work without it.

David Newman
May 4th, 2007, 12:32 PM
ATI only tends to get the YUV levels correct with the overlay switch on. I use an ATI 9800Pro and the levels are spot on.

Tim Homola
May 4th, 2007, 12:33 PM
Actually, I spoke too soon. Things are still screwed up. I'm working on it.

Brad Tyrrell
August 8th, 2007, 12:29 PM
Just thought I'd mention, - I had the same brightness shift between stills and playback, but I don't have a card. I have Intel Integrated Graphics.

I went to the control panel, opened up the GMA driver control, increased the overlay brightness from 7 to 17 and now everything matches. Don't know how accurate anything is, but stills match scrub match playback.

Rafael Lopes
September 25th, 2007, 11:47 PM
I have an nvidia card and I have the same problem. I was thinking about getting a matrox parhelia, since it's one of the official cards supported by aspect hd (and since, according to David Newman gets it all right). Is anyone with this card experiencing the same problem?

Matt Vanecek
January 1st, 2008, 05:30 PM
I have the GeForce 6600 video card installed. I also have the 169.21 Forceware installed, and there is not an option to go to the "Classic" view. So there is not any overlay settings that I can find in the new nVidia control panel.

Here are my project playback settings:

checked: Enable Overlay Surface
unchecked: De-interlace video
checked: Use HD Colorspace
checked: Use video systems RGB
unchecked: Disable preview mode
checked: Force YUV Desktop playback
Memory size: Max


When scrubbing through my AHD project in PPro 1.5.1, using AHD 5.2.2b101, there is a significant brightness gain during scrubbing as opposed to simply viewing. Changing the settings in the nVidia control panel does not have any effect on the levels difference between scrubbing and holding still (overall screen levels are changed, of course--but there is still a noticeable difference between scrubbing and not scrubbing). I've changed about every setting in nVidia control panel WRT video, and while the changes were definitely reflected in the video playing, the relative level difference between scrubbing & not scrubbing was always quite evident.

I uninstalled 5.2.2b101, and regressed to 5.2.1b98. There is now no discernable difference between scrubbing and playing, with respect to levels. There's still some blur going on during scrubbing, but I think that's expected.

It appears from my empirical efforts that there is a problem with 5.2.2b101. Could somebody besides myself confirm this? I'm only reporting what my eyes are seeing....if I need to I can file a trouble ticket.

I don't much care for the new nVidia interface, but I'm not sure how to get the old interface back without regressing drivers. :(

Thanks,
Matt

Matt Vanecek
January 1st, 2008, 09:15 PM
Just as an update, I returned my GeForce driver to the previous level (89.91 or something like). AHD 5.2.1 still works great, but AHD 5.2.2b101 still exhibits the disturbing level change between still and scrub.

ciao,
Matt

Matt Vanecek
January 2nd, 2008, 11:17 PM
I went ahead and opened trouble ticket #611-5530276 on this, since there is definitely a difference between 5.2.1b98 and 5.2.2b101. 5.2.2b101 seems like it's ignoring the YUV settings or video card settings or whatever. I attached screen shots of my CF playback settings, the nVidia color correction settings, and the nVidia Video Overlay settings. The settings I attached in the ticket work on 5.2.1b98, but nothing works on 5.2.2b101.

Thanks,
Matt

David Newman
January 2nd, 2008, 11:25 PM
This scrubbing error is actually not related for thread about preview playback. However, I believe have have just fixed it. New builds hopefully in the next few days.

Matt Vanecek
January 3rd, 2008, 08:28 PM
w00t! I'll keep a weather eye out.

Thanks,
Matt

Michael DAmbrose
January 12th, 2008, 10:08 AM
So, Is there a way to scrub/preview with the proper brightness/contrast when using AspectHD and PremierePro? I am going nuts trying to get the image right. The cookbook setting found when searching this forum were for the old Nvidia driver.

Still this is a bug in Cineform in my opinion.

Graham Hickling
January 12th, 2008, 02:36 PM
Yup - download the latest version of Aspect HD and uncheck "Force YUV" in playback settings. On my Nvidia GS7600 doing this fixed the issue perfectly.

I agree that the advice on the Cineform website has no longer been applicable for recent Nvidia drivers.

Michael DAmbrose
January 12th, 2008, 03:03 PM
I just downloaded Build 104 and it works with the Force YUV off. Graham, thanks for the help!