White Pixel popping on Colour Page - Not In Render...

I'm working on the Colour Page getting some testing done and pushing some clips pretty hard with heavy adjustments and also using DCTL's in the workflow (masking / noise filter / blur / sharpening). I'm getting some white and black pixels that pop during playback but disappear when not playing the clip. The renders are clean with no popping. Wondering if others have seen and/or experienced this? See attached screen capture.

Running...

Resolve 18.5.6
Windows 11 (23H2)
Dual Nvidia RTX 3090 (latest Studio Driver - 551.86)

Should also note that there's no clipping in the scopes.

On my office system I have noticed similar behavior when having complex grades with DCTLs involved as well but mines were typically coming from negative values from out of gamut stuff/funky specular things or noise. Good to know it's only a viewer playback thing, don't have a solution though.

Usually putting "Color Space Transform" node and turning on: Saturation Preserving: This option has a smooth luminance roll-off in the shadows and highlights, but does so without desaturating dark shadows and bright highlights, so this is an effective option for colorists who like to push color harder. However, because over-saturation in the highlights of the image can look unnatural, two parameters are exposed to provide some user-adjustable automated desaturation.

Most of the time that will do the trick. Also if you are doing fusion stuff and you are seeing this in color page, make sure there are no negative values in Fusion. Just use Brightness Contrast [BC] node and make sure that these options are turned on.

Clip Black/White

The Clip Black and Clip White checkboxes clip out-of-range color values that can appear in an image when processing in floating-point color depth. Out-of-range colors are below black (0.0) or above white (1.0). These checkboxes have no effect on images processed at 8-bit or 16-bit per channel, as such images cannot have out-of-range values.

Pre-Divide/Post-Multiply

Selecting the Pre-Divide/Post-Multiply checkbox causes the image pixel values to be divided
by the Alpha values before the color correction, and then re-multiplied by the Alpha value after
the correction.

This helps to prevent the creation of illegally additive images when color correcting images with premultiplied Alpha channels.

The reason why it may not be appearing in the render is because some codecs turn on Rec709 and other options automatically in the Delivery Page. Anyway, when I encounter those issues, especially as mentioned with complex grades with DCTLs or complex Fusion comps, that is what I do and it solves the issue most of the time. Its just illegal out of gamut stuff happening that goes beyond color space of the project, monitor and output codec so you have to tame them.

If that does not help, not sure, maybe make sure you have no wild color settings in the project or color conversion nodes, including sometimes faulty or not well optimized DCTLs.

Hope it helps.

All great input - thanks to you both. I'll run through my nodes and check for negative settings that may be affecting things. I do use a fixed node tree using CST's (IN / OUT) with the Saturation setting active on the CST OUT. Working with colour management in the node tree (Davinci Wide Gamut / Davinci Intermediate). I'll test out the other settings to see if they resolve the issue.

The DCTL's are from Mono Nodes, Kaur Hendrikson and Pixeltools. I'll check with them also to see if there any known gotcha's or issues to look out for.

The DCTL's are from Mono Nodes, Kaur Hendrikson and Pixeltools. I'll check with them also to see if there any known gotcha's or issues to look out for.

I get the same problems with the Mononodes HSV Saturation DCTL. I assumed it was a Resolve bug and went back to doing it manually.

Resolve studio 18.5 Nvidia 3080

I can't put my finger on any one DCTL but they do seem the likely culprit. Definitely in combination with any noise filtering or sharpening things seem to pop and fall apart. I'll continue to test things and see if I can narrow down what combination of things cause this.

I can't put my finger on any one DCTL but they do seem the likely culprit. Definitely in combination with any noise filtering or sharpening things seem to pop and fall apart. I'll continue to test things and see if I can narrow down what combination of things cause this.

I just wanted to reply after some testing of my own and yeah, I'm getting the same feeling that its the DCTL problem, especially in certain combinations and with some settings. I guess its not all compatible. But with some care, mots of them can be used safely it seems.

Sorry if this has already been covered, but did I understand that the artifacts are only present during playback? If so, is it possible that this issue is related to the playback optimization that is turned on by default? I am not in front of my machine at the moment but there is an option to make playback a bit faster by doing less processing and if you turn this option off, do you still see the artifacts?

Steve - I'll check this today and report back.

I think I might have found a solution for working with DCTLs and getting strange artifacts. There is another DCTL I found called "softclip". I can't remember where I downloaded it, probably github,. I'll try to upload it here.

Softclip.zip

Here is the mentioned DCTL for limiting the colors and clamping down on those weird artifacts.

(348 Bytes) Downloaded 52 times

Use it after your other DCTL and other adjustments. I used it in Fusion page and solved me a load of problems.

As you can see when working on projects like these, especially in Fusion's 32 bit float and linear space. You can get negative values and all kind of issues when working with DCTLs and mixing colors and adding blend modes.

Honeyview_Timeline 219_00_00_10_23.jpg (61.75 KiB) Viewed 678 times

If those artefacts only appear during playback, I would look at the playback optimization settings, too.

Sorry if this has already been covered, but did I understand that the artifacts are only present during playback? If so, is it possible that this issue is related to the playback optimization that is turned on by default? I am not in front of my machine at the moment but there is an option to make playback a bit faster by doing less processing and if you turn this option off, do you still see the artifacts?

Steve - nailed it. I disabled this in Preferences and the popping / glitches seem to have gone away. Interesting side note is that when the node had Render Cache activated, the cached version had no popping to it. This should be useful information to anyone else who comes across this issue.

Thanks for the feedback and solution here!

I can confirm we see similar behavior with DCTLs.

It does make me think though if there are any problems with the DCTL still. As I am coding DCTLs as well I do stumble upon similar issues all the time and fix them in the code. Maybe someone can really stress test those particular DCTLs?