viewfinder dust

[sedwards]

i can see a lot of dust in the viewfinder on my 1DsIII and i cand seem to get it out with a blower. i tried removing the rear portion of the viewfinder but the dust is on the inside. if the light is right i can see a lot of junk when looking through there but i dont see any spots on my pictures .
any ideas on how to clean it out ?

[Jonathan Huyer]

Hmmm.... the only dust I ever try to remove is on the focus screen (or whatever it is you call that opaque horizontal glass at the bottom of the prism), and the mirror. I use a LensPen brush and that works great. Beyond that you might be looking at sending it in for repair.

[M_Six]

When I replaced the focus screen in my T1i with a Katzeye screen, I ended up with some dust in the viewfinder. I tried removing the Katzeye screen and blowing the dust out with a rocket blower, but really only succeeded in moving the dust specs around. It's not easy to get out and chances are good you'll just let more in.

[neuroanatomist]

The dust could be on or behind the focus screen, which you can remove and clean. It can also work its way up into the pentaprism assembly, in which service is required. In the latter case, I wouldn't bother unless it's like a sandstorm in there – as you note, it won't affect your images.