G'day all, not sure if this is the right place to post this (please let me know if it's not).

I have a 14" AcerView 34e CRT monitor from 1997 which I use with my retro computers. It's has good colours and a good image and all, but it does have that problem with the image shrinking and expanding based on brightness (switching from a dark screen to a light screen will cause the whole image to expand slightly, and switching back to a dark screen will make the whole image shrink again).

It's something I can somewhat live with, but it's just a bit irritating, because the CRT monitor I had before (15" LG StudioWorks 57i) didn't seem do this, or at least it wasn't all that noticeable if it did.

I've done some research on the issue and it's apparently called "image bloom", and it's the result of poor HV regulation inside the unit (I've also read it can be caused by ageing capacitors). Not sure how much of that is true, as I still don't know much beyond how it creates the picture and how to safely discharge a tube. I'm still learning.

Is there any potential way to eliminate or at least reduce this effect so the picture is more stable when switching from dark screens to light screens and vice versa?

Thanks in advance!

- UltimateElectronicFun