Hair Line Cracks

[Diyisfun]

I have a new plastered wall (completed 8months ago) I have given it an emulsion wash to seal it and I have noticed 2 hair line cracks that are long & unsightly.
I intend using a paint finish on this wall & would like to hide these cracks. I tried on a small section opening the crack & used polyfilla, but that looks as bad as the hairline crack.
What is the best way to deal with hairline cracks. (I have assumed now that any settlement & drying would be complete).

 

[masona]

I always use Gyproc Easi-Fill, a very fine filler, one of the best filler I've ever use.

 

[Mr Ben]

if very fine you can use a decorators caulk. It will sand after drying for 24hrs.

 

[Julio]

If it is a timber stud wall, you may still get some movement.