when using a brush in a mask is causing LR to slow down

[RAW Photography66]

Just noticed LR running very slow when I use a brush in a mask, the little swirling circle in the bottom right corner of the screen, I think this is the CPU rendering, will keep swirling and not seam to make the adjustment. All other tools work fine, radial and linear gradients, add and subract are all operating fine, only when I use the brush.

[Ian Lyons]

It would be helpful if you provided more details on your setup.

1. Computer specs including CPU and memory, GPU and VRAM, etc

2. Version of Windows you're using

3. The actual version of LrC you're using. The latest is 11.4.1. So, make sure that's the version you have installed.

[dj_paige]

Are you talking about Lightroom (Lr icon) or Lightroom Classic (LrC icon)?

I think we would also need to know the size of your original images in pixels or megapixels (not megabytes), and the size of your monitor in pixels (width x height, not inches).

[RAW Photography66]

Hi all, I had Adobe take a look at the issue as it was bugging me, I tried the test recommended in the group and it did lead me to believe it was my graphics card which the Adobe support did confirm it was the issue. I now know what I need to do, this will be upgrade 3 to my computer in the last 2 months, I don't think there will be anything left in it that was an original part after I change this. Thank you all for your answers.

[Ian Lyons]

If you're going to replace the graphics card, then make sure you buy one that meets the recommended requirements for 'full GPU acceleration' (i.e. 8GB of dedicated VRAM see link below).  If you buy a card with anything less than 8GB, then you're going to miss out on the performance benefits of the recently introduced GPU accelerated export, and any future updates requiring a GPU.

https://helpx.adobe.com/uk/camera-raw/system-requirements.html#GPU

[RAW Photography66]

Hi Ian, I spoke to my IT shop and he said he cant change the GPU as I use a laptop, not sure if thats correct, I will check with Lenovo directly in their service center.

[dj_paige]

You didn't answer any of our questions.

[RAW Photography66]

Windows 10 Home

CPU Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz 2.59 GHz

VRAM 40.0 GB (39.9 GB usable)

GPU NVIDIA GeForce GTX 1650 Ti

1TB SSD Main drive

1TB HDD drive

Image size 8256 x 5504

Display 2560 x 1440

LRC 11.4.1

[dj_paige]

So its no surprise that trying to do a lot of brushing on a 45MP image will slow down. Have you tried turning OFF the graphics acceleration in LrC (Preferences->Performance->Use graphics processor)? Your monitor is not 4K, so having the graphics acceleration on might actually be the culprint.

[RAW Photography66]

Actually, when we turned it off yesterday it worked far better, no lagging at all, would this be the best way to work? I assume its not a necessity to have it on?

[dj_paige]

The GPU helps most in Lightroom Classic with 4K or larger monitors, which you don't have.

[ritab53961173]

After struggling for months this worked thank you so much !!!

[seanc23257002]

Thank you for suggesting this!  I have an RTX 3060 Ti which is a pretty solid card, and yet I was getting a ton of lag.  Sometimes the interface would go black and I'd get the little spinney icon while waiting for it to refresh.  With 'Use Graphics Processor' turned off, now the brush is only slightly behind my stroke motion, but this is absolutely usable now.  Thanks again!