The ideal solution for hanging pictures on plaster is to use a picture hanging system like the all in one click rail cable hanging kit.
T mount for double plaster walls.
Never mount an articulating mount onto plaster walls please it is not safe and if anyone tells you otherwise then they in all honesty should not be mounting your tv to a plaster wall or any other wall for that matter.
Expect most mounts to have 4 or 5 of them.
For lighter items simply screwing into the plaster with a 1 1 4 drywall screw is usually enough to get the job done.
Mark the location of the mount s screw holes with a pencil.
Make sure these marks are clear so you know where to anchor the mount to the wall.
While holding it in place look for the holes.
In some cases explanation.
Plaster walls are not the most ideal material for mounting a television too however it can still be done with care.
10 best tv wall mounts for plaster walls reliable affordable durable.
This system works by simply installing a rail along the wall and pictures then hang from cables attached to the rail and are fastened with hooks.
Keep the mount pressed against the wall.
Make sure the screw holes line up with the nearest studs.
How to hang on plaster walls with a picture hanging system.