dirty focusing screen

[bastic]

hey.
I borrowed Nikon FM from a collegue at work.got it home and find out that focusing screen is dirty...
I know it wont affect pictures but its really really annoying...any ideas how to clean it ?
thanks

 

[Digital_Clarity]

Cotton bud?

 

[CT]

Have Fun!

 

[bastic]

Have Fun!

thx CT...seen that already
managed to take the screen out....and put it back...but I still have one bit left that I could not put back its some kind of spring frame ( or how to call it heh ) but it works...for now ...and yes..its not my camera
Im off on thursday and friday and I will pay a visit to Fixationuk and let them play with it

 

[sprog]

That spring frame thing is usually a brass shim that corrects for slight misalignment of the mirror/split prism and film plane so that the focussed image in the viewfinder transposes correctly onto the fillum. It's probably worth putting it back