Image blinking after applying effects in PProCS3 at DVinfo.net

Jose Milan · August 29th, 2007, 06:48 AM

Hello,

I've apply auto color, auto contrast and focus mask (70,1,0) in Premiere Pro CS3 to a simple video of a person against a whiteboard (the person writing in the whiteboard) and after exporting and viewing the video there's a problem with the image. The white of the whiteboard change its illumination and looks kinda like is blinking, is not as fast as burst of flash, but is fast enough to notice.

Does anyone knows whats going on and how to solve this problem???

Thanks in advance.

Dale Stoltzfus · August 29th, 2007, 06:55 AM

Are you working in 8-bit color space? If so, that could be your problem. I've never experienced this, but I've heard that applying multiple effects to a video when working in 8-bit is asking for trouble. Try switching the project settings to 16-bit and see if that works (you might have to re-apply your effects).

EDIT: actually that may not be your problem - I can't find a way to change the color space in Premiere.

Jose Milan · August 29th, 2007, 07:57 AM

Can't find the bit depth either so might not be an option.

Lloyd Coleman · August 29th, 2007, 09:57 AM

The blinking is probably caused by using the 'auto' color and contrast settings. In auto, each frame is evaluated one by one and a different correction is made to each frame. As the subject, lighting, etc. changes from frame to frame the correction is different. When there is a constant subject (such as the whiteboard) that does not change you will see the effect of the different settings that 'auto' applies to each frame. You can often minimize this blinking by applying 'Temporal Smoothing' to the 'Auto Color' and 'Auto Contrast' effects. In the 'Auto' effect control window try a few diffent settings for the temporal smoothing option. This makes the effect average several frames together rather than adjusting them frame by frame and should smooth out the blinking you are seeing.

Another (probably better) option is to not use the auto controls and apply the corrections using other effects such as the regular Levels control, the Fast Color Corrector, or any of the other non-auto controls.

Jose Milan · August 30th, 2007, 04:24 AM

Hello Lloyd,

What you said seems very logical and almost sure has to be the problem and the answer. I'm going to check and try what you said.

Thanks,

Jose

Jose Milan · September 4th, 2007, 04:00 AM

Sorry for the late reply...that was the problem, using auto touch-ups, using regular manual tools solved the problem.

Thanks.

Urban Skargren · September 5th, 2007, 01:29 PM

I have a general question about effects: I know brightness filters affect definition, but do color effects?

August 29th, 2007, 06:48 AM	#1
Jose Milan Regular Crew Join Date: Jun 2007 Location: Spain Posts: 185	Image blinking after applying effects in PProCS3 Hello, I've apply auto color, auto contrast and focus mask (70,1,0) in Premiere Pro CS3 to a simple video of a person against a whiteboard (the person writing in the whiteboard) and after exporting and viewing the video there's a problem with the image. The white of the whiteboard change its illumination and looks kinda like is blinking, is not as fast as burst of flash, but is fast enough to notice. Does anyone knows whats going on and how to solve this problem??? Thanks in advance.

August 29th, 2007, 06:55 AM	#2
Dale Stoltzfus Major Player Join Date: Jun 2007 Location: Ephrata, PA United States Posts: 257	Are you working in 8-bit color space? If so, that could be your problem. I've never experienced this, but I've heard that applying multiple effects to a video when working in 8-bit is asking for trouble. Try switching the project settings to 16-bit and see if that works (you might have to re-apply your effects). EDIT: actually that may not be your problem - I can't find a way to change the color space in Premiere.

August 29th, 2007, 07:57 AM	#3
Jose Milan Regular Crew Join Date: Jun 2007 Location: Spain Posts: 185	Can't find the bit depth either so might not be an option.

August 29th, 2007, 09:57 AM	#4
Lloyd Coleman Major Player Join Date: Oct 2003 Location: Salt Lake City, UT Posts: 256	The blinking is probably caused by using the 'auto' color and contrast settings. In auto, each frame is evaluated one by one and a different correction is made to each frame. As the subject, lighting, etc. changes from frame to frame the correction is different. When there is a constant subject (such as the whiteboard) that does not change you will see the effect of the different settings that 'auto' applies to each frame. You can often minimize this blinking by applying 'Temporal Smoothing' to the 'Auto Color' and 'Auto Contrast' effects. In the 'Auto' effect control window try a few diffent settings for the temporal smoothing option. This makes the effect average several frames together rather than adjusting them frame by frame and should smooth out the blinking you are seeing. Another (probably better) option is to not use the auto controls and apply the corrections using other effects such as the regular Levels control, the Fast Color Corrector, or any of the other non-auto controls.

August 30th, 2007, 04:24 AM	#5
Jose Milan Regular Crew Join Date: Jun 2007 Location: Spain Posts: 185	Hello Lloyd, What you said seems very logical and almost sure has to be the problem and the answer. I'm going to check and try what you said. Thanks, Jose

September 4th, 2007, 04:00 AM	#6
Jose Milan Regular Crew Join Date: Jun 2007 Location: Spain Posts: 185	Sorry for the late reply...that was the problem, using auto touch-ups, using regular manual tools solved the problem. Thanks.

September 5th, 2007, 01:29 PM	#7
Urban Skargren Major Player Join Date: May 2007 Location: Medellin, Colombia Posts: 225	I have a general question about effects: I know brightness filters affect definition, but do color effects?