Scratch or Dirt

I am at college in the middle of rural Iowa, without a bat's chance

in hell of getting to a camera shop before December 20th. I have a

Nikon FM2, and I'm really a beginner photographer with just a few

years of sporadic shooting under my belt. Here's the problem: today I

noticed a black vertical line on the upper half of the inner-most

circle when I look through the viewfinder. I thought: okay, dirt. A

hair. I can deal. But when I point the camera at a bright light and

the semicircle goes black, the line appears white. So now I'm

thinking: scratch?

 

I've got to develop some test pictures, I know. But can anyone tell

me what this sounds like, whether its advisable to clean the viewing

glass (I found instructions for doing so on a few web sites...),

experiences with repair if it is on the mirror, etc?

 

Also, is it okay to blow some compressed air on the mirror from a

safe enough distance? I do have a little bit of dust in there when I

remove the lens and peer in (though I can't identify the source of

the original problem).

 

Thanks for your help.

Your first inclination is probably right--dirt or a hair. Scratches don't just happen unless you've been poking around inside the camera body. Whatever the case, and it is most likely some crud on the focusing screen, it's *not* going to affect your photos. Once you press the shutter release, the mirror flips up and the image hits the film directly. When you get a chance, buy one of those blower brushes and gently brush and blow the bottom of the screen. Until then--just ignore it.

Just don't touch the mirror under any circumstances with the brush. I would be inclined to blow the screen only, don't touch it with the brush. Its soft plastic and easily scratched.

 

The screen comes out of the FM2n but I wouldn't do this unless you have someone with you that knows what they are doing. If you search the archives here, you'll find many instances where people have damaged their screens and mirrors over dust that doesn't affect their photos.

Good advice above. Don't let the dirt/hair/whatever bother you - as has been said, it will have no affect on the image. If you <I>must</I>, it's possible to blow compressed air onto the focussing screen (which is made of ground glass, not plastic), but you need to do it in such a way that propellant doesn't come out of the can and screw everything up - you accomplish this by making sure the can is upright and the blowing tube a good distance (an inch or two) from the screen. And, whatever you do, don't blow air onto, or touch, or otherwise molest, the mirror. Overall, I wouldn't go cleaning crazy in the viewfinder or worry about minor debris there - it's normal.

many times one gets more dust/dirt onto the screen than off. like

suggested above, it shouldn't be much of a concern.

---billy

Actually, I *think* that the screens for the FM2n are acrylic plastic. My F3HP uses real glass screens. In any case, the fresnel on the bottom is certainly made of plastic.

It is on the focussing screen. If it were not, it would not be sharp. If it does not bother you, don't worry about it: it will have no effect on your pictures!

 

Alex