Photshop layer mask not working properly????

[trostt19622370]

I open an image in photoshop, duplicate the image, so I'm not working on the original. Click the eyeball off on the original. On the duplicate layer, create a layer mask to reveal all. Choose my brush with black selected and start painting, but no effect, but I can see in the layer mask it has removed the selection I have painted. If I turn on then off the original photo via the eyeball the work on the duplicate then shows up. If I start painting again on the layer mask, I can see its working, but the work will not show up unless I turn on and off the originial photo again. Thanks

[JJMack]

That sounds about right to me.  The parts you hide in the duplicate reveal the  original pixels in the lower original layer. 

Maybe this will help

[trostt19622370]

If the bottom layer is turned off, the mask should show the work, but instead, it acts like the bottom layer is still turned on and does not show my work. Here is a screenshot that shows the bottom layer turned off, and on the duplicate layer above shows the layer mask has been painted in with black, but is not showing the masked out area in the photo itself.

 

[JJMack]

Yes that is not right do as Dave wrote and you should have no problem.

[davescm · Accepted solution]

If visibility of your original layer is off then that does not sound right.

Try going to Preferences > Performance and uncheck legacy compositing. Then close and restart Photoshop.

Dave

[trostt19622370]

That seemed to work, any idea why turning that off made all the difference...and Thanks

[JJMack]

Adobe broke Legacy Compositing in the 21.2 update

[davescm]

The compositing engine at the very heart of Photoshop has been changing in recent versions. The "legacy compositing" option was there as a fallback in case those changes caused an issue on particular systems. However in v21.2 it was that fallback option that showed the issues so turning it off and using the newer compositing engine resolves the issue you described.

Dave