Restore clipped highlight detail in Premiere Pro CS3 with superwhites - Page 2

Graham Hickling · May 30th, 2008, 01:40 PM

Wow. That IS weird!

Jyrki Hokkanen · August 15th, 2008, 08:23 AM

Sorry for the late response but I only just ran into this thread. I tested the provided footage and my Premiere CS3 behaved exactly like Daniel Browning described. I opened a fresh project with the basic NTSC HDV settings, and both the Levels and RGB Color Correction filter clips the whites, while Fast Color Correction does not. The scopes show that just adding either of those two bad behaving filters to a piece of footage, results in the whites being clipped, even if the filter settings were not touched. Lowering the white levels does not bring back the details, they stay clipped.

Jyrki Hokkanen · August 18th, 2008, 08:04 AM

I had a more thorough look at the can - here are the worms.

The following filters are good for bringing down the superwhites recorded by the camera: Fast Color corrector, Three-Way Color Corrector, Luma Curve, RGB Curves, ProcAmp.

Combining any of the following to the stack will clip the superwhites even if the above "good" filters have been used to bring them down below 100IRE: Levels, Shadow/Highlight, Color Balance, Color Balance (HLS), Tint, Gamma Correction, and probably most of the rest. Also, RGB Color Corrector and Luma Corrector cannot bring superwhites down and clip the superwhites if used before one of the "good" highlight adjusting filters. RGB Color Correction always clips the chroma.

All of this works when exporting to tape, or exporting to movie. Does not work when using Adobe Media Encoder, unfortunately!

Exporting via Media Encoder always results in the original superwhites being clipped, even if the superwhites were brought down to legal values with the "good" filters. It appears that Media Encoder first clips superwhites and only then applies the filters. MainConsept MPEG Video codec, or its implementation, seems to be buggy.

As a work around, before using Media Encoder, export the parts with corrected superwhites to movie, preferably with a non-lossy codec, and import back to your project.

Note that RGB Parade seems to always show whites as clipped, even if they are not. Use All Scopes or Vect/YC Wave/RGB Parade to check the RGB values. The other scopes work as expected.

Jyrki Hokkanen · August 20th, 2008, 04:17 AM

A minor update to my previous post:

Quote:

Originally Posted by Jyrki Hokkanen

Note that RGB Parade seems to always show whites as clipped, even if they are not.

Selecting the Maximum Bit Depth video rendering option in Project Settings makes the RGB Parade scope show the superwhites properly. Does not fix anything else, though.

The filters understanding superwhites are tagged as "high bit-depth" in the Adobe Premiere Pro Help manual.

Graham Hickling · August 20th, 2008, 06:49 AM

Hey this is great info - appreciate the effort you have put into clarifying this!

Daniel Browning · September 24th, 2008, 01:17 AM

I don't see anything in today's Premiere Pro CS4 announcement that makes me think this issue is fixed. (If it were, I would have expected Adobe to tout it's increased dynamic range handling and highlight recovery options.) But we'll see about it when it comes out.

Daniel Browning · December 4th, 2008, 02:58 PM

Quote:

Originally Posted by Daniel Browning

I don't see anything in today's Premiere Pro CS4 announcement that makes me think this issue is fixed. (If it were, I would have expected Adobe to tout it's increased dynamic range handling and highlight recovery options.) But we'll see about it when it comes out.

I tested 4.0.0 and found no improvement. I continue to restore superwhites with RGB curves or FCC.

August 18th, 2008, 08:04 AM	#18
Jyrki Hokkanen New Boot Join Date: Oct 2003 Location: Helsinki, Finland Posts: 9	Adobe Media Encoder forces clipping I had a more thorough look at the can - here are the worms. The following filters are good for bringing down the superwhites recorded by the camera: Fast Color corrector, Three-Way Color Corrector, Luma Curve, RGB Curves, ProcAmp. Combining any of the following to the stack will clip the superwhites even if the above "good" filters have been used to bring them down below 100IRE: Levels, Shadow/Highlight, Color Balance, Color Balance (HLS), Tint, Gamma Correction, and probably most of the rest. Also, RGB Color Corrector and Luma Corrector cannot bring superwhites down and clip the superwhites if used before one of the "good" highlight adjusting filters. RGB Color Correction always clips the chroma. All of this works when exporting to tape, or exporting to movie. Does not work when using Adobe Media Encoder, unfortunately! Exporting via Media Encoder always results in the original superwhites being clipped, even if the superwhites were brought down to legal values with the "good" filters. It appears that Media Encoder first clips superwhites and only then applies the filters. MainConsept MPEG Video codec, or its implementation, seems to be buggy. As a work around, before using Media Encoder, export the parts with corrected superwhites to movie, preferably with a non-lossy codec, and import back to your project. Note that RGB Parade seems to always show whites as clipped, even if they are not. Use All Scopes or Vect/YC Wave/RGB Parade to check the RGB values. The other scopes work as expected.

September 24th, 2008, 01:17 AM	#21
Daniel Browning Major Player Join Date: Jan 2007 Location: Portland, OR Posts: 459	Superwhite handling in CS4 I don't see anything in today's Premiere Pro CS4 announcement that makes me think this issue is fixed. (If it were, I would have expected Adobe to tout it's increased dynamic range handling and highlight recovery options.) But we'll see about it when it comes out.

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May 30th, 2008, 01:40 PM	#16
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,117	Wow. That IS weird!

August 15th, 2008, 08:23 AM	#17
Jyrki Hokkanen New Boot Join Date: Oct 2003 Location: Helsinki, Finland Posts: 9	Sorry for the late response but I only just ran into this thread. I tested the provided footage and my Premiere CS3 behaved exactly like Daniel Browning described. I opened a fresh project with the basic NTSC HDV settings, and both the Levels and RGB Color Correction filter clips the whites, while Fast Color Correction does not. The scopes show that just adding either of those two bad behaving filters to a piece of footage, results in the whites being clipped, even if the filter settings were not touched. Lowering the white levels does not bring back the details, they stay clipped.

August 20th, 2008, 06:49 AM	#20
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,117	Hey this is great info - appreciate the effort you have put into clarifying this!