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Slow mask brush ON1 Photo Raw 2023 M1 Mac



  • Brian Lawson Community moderator

    There can be multiple causes for the brushing lag. They all come from the fact that the brush movement is tracked by the GPU which is simultaneously re-rendering your image as you are brushing. This is what the Video Card Strength slider is for in Preferences > System > Performance. Moving the slider right tells the program to spend more GPU time on rendering so you can move it left to get better brush tracking performance.

    Turning on Fast Preview will also improve brush tracking as it tells the program to do less rendering while brushing. You'll see a lower res version of the image while brushing.

    The Performance settings are covered on page 265 of the User Guide.

    The Editing Pipeline (pg 74) also has an affect on brushing. When you are working on a mask that is at the beginning of the pipeline (lower in the editing stack) everything that comes after that point has to be re-rendered. The more stuff there is in the pipeline the longer it will take to do the rendering and the more stuttering you'll see. This is especially true when processor intensive features are used like Blending Modes and Effects like Dynamic Contrast. Temporarily turning off Effects above where you're working can help improve brushing performance.

  • Barb Harvill


    Thank you for the tip to turning off Effects above where I was working.  Worked like a charm. 

    I was doing a local adjustment and the masking was so slow I couldn't even move the brush after pressing left mouse button. Took minutes to return screen.  Same with pressing view for mask or changing view zoom.   I turned off all effects (no local adjustment was above the one I was working on) and it was magic.

    FYI My system:

    Intel I9-9000 3.10GHz

    32 GB ram

    current windows 10 version 22H2

    All drivers updated including latest Video card NVIDIA driver

    Moved Scratch folder to external SSD drive

    Have changed system preferences to video card strength to high and checked GPU render and fast preview



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