Polygonal Lasso Tool

Jul 2, 2019
Lightroom Version
Lightroom Classic version: 11.1 [ 202112022200-7fd1f998 ]
Operating System
  1. macOS 10.15 Catalina
Is anyone having trouble with the polygonal lasso tool in Photoshop shifting its selection before it is completed? This is driving me nuts! Been going on for some time, like three months. Updated to Catalina Version 10.15.7, updated to PS 23.1, updated to Lightroom 11.1, but it continues to happen. Primarily when zoomed to 100%. About halfway through a somewhat complicated selection, it suddenly shifts the part that has been partially selected about 50 pixels (sometimes more; sometimes into a grid!), which sits on top of the original file, but duplicated and offset. The only thing i can figure out to do at that point is to escape the selection, resize the image to fit on the screen, then start all over again.
It seems that my computer is having trouble processing the changes as quickly as i am working, so the obvious answer is to slow down.
I am working from files made on a Nikon D850, so admittedly, these are much larger than i was working with from a Nikon D3X. Maybe that is the only difference, and my expectations are wrong. Any corroboration or sympathy or suggestions are always welcome. Happy New Year!

iMac (Retina 5K, 27-inch, 2020)
Processor 3.6 GHz 10-Core Intel Core i9
Memory 64 GB 2667 MHz DDR4
Graphics AMD Radeon Pro 5700 XT 16 GB


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Jul 2, 2019
i do appreciate your observation, but the symbiotic way in which the two different programs, apps, software are connected, not to mention the quality of conversation in this forum, i thought someone might have a helpful comment.
May 12, 2011
Lightroom Experience
Lightroom Version
You're in the correct forum.

Personally, I don't use PS enough to have encountered this. On the face of it, it's hard to say if it's a hardware problem or a software bug. It is an error of some sort. Are your video card drivers up-to-date? How much free space do you have on your system disk?