Dirt in my Viewfinder

When I look through my viewfinder, I see a few random spots of dirt. I know it's in the camera body because this happens with every lens I use. There have been no stray marks in my photos, so I haven't really worried about it too much. I've tried cleaning off the outside of the viewfinder, and no change. The mirror appears to be clean, so it must be inside the body somewhere. Does anyone have any advice on how to clean this out or if I should even bother? Like I mentioned, it's not in any of my photos, so there's no loss in image quality. It seems like the negatives would far outweigh the positives in any attempt to clean that out.

I wouldn't worry about it.
It's probably up in the prism and nearly impossible to get to without pulling it apart.

There's an instruction how to clean the prism/viewfinder on 5D, ....I posted a link here about 2 years ago.

However, you will probably add more dust ...

Best thing is to learn to ignore it as it doesn't affect picture quality.

philwillmedia wrote in post #16238463
I wouldn't worry about it.
It's probably up in the prism and nearly impossible to get to without pulling it apart.

rxjohn wrote in post #16238488
There's an instruction how to clean the prism/viewfinder on 5D, ....I posted a link here about 2 years ago.

However, you will probably add more dust ...

Best thing is to learn to ignore it as it doesn't affect picture quality.

Yeah, I'd say just ignore it unless you are confident in your ability to disassemble and reassemble your camera!

Here's the instruction for 5D

http://www.ascent-design.com/photo/Clean​5D/

tonylong wrote in post #16239564
Yeah, I'd say just ignore it unless you are confident in your ability to disassemble and reassemble your camera!

I'm really not.

Thanks for the instructions rxjohn. Given how delicate everything is, I think I'll just deal with it for now.

Dust visible in the viewfinder is most likely on one of the surfaces of the focusing screen. If the camera in question is your T3i, these are not made for user-removable focusing screens, so you need to undo some screws to get the focusing screen out, while cameras with focusing screen options from Canon are very easy and simple to remove. Focusing screens are plastic and quite easily marred by the unknowing! I advise to NEVER dry wipe, but wash only under running water before a final rinse in distilled water, then stood on edge to air dry only...never blot dry.

Don't screw with a camera that has a transmissive display!

DO NOT TOUCH that T3i focusing screen. I've done it and regretted it. Removal is super easy. You don't have to unscrew anything. Putting it back on is a whole different story. I ended up sending it back to Canon.

I have one on the top of my focus screen on my 5D III. It makes me sad, and makes my OCD go crazy. But I am working hard to ignore it.

Every SLR I've had has wound up in the same predicament. What can you do? Professional cleaning is really the only option, but you'll probably wind up getting another one anyways. I would get the camera cleaned only when you have several spots.

Another reason to go mirrorless

I have lots & lots of big stuff in my viewfinders. It's just normal. As you said, it doesn't affect anything that matters, so there's really no reason to bother trying to get rid of it. It's as meaningless as bugs and bird poop on your windshield - if you remove them, more will immediately take their place . . . so why bother?

Most it is a simple fix. Take the lens off and turn camera upside down. Lightly bow up in the area of the viewfinder.

Never blow with your mouth, only a air bulb blower, and never compressed air. You'll destroy your mirror.

I had a few dust bunnies in my prism on my 5D3 that I would not get out with a bulb blower... Sent in for a check/clean and it came back spotless. Although recently, I just got a few more dust bunnies up there again so its a bit of a bummer... Hoping when I send my body in this winter they will clean it out again for me, because I know it can be labor intensive on some bodies I believe.

It sounds like pentaprism dust. I ignored mine for years but got very tired of having other users ask about the mess and having to explain in short sentences why it was OK, why it didn't bother me, why I was OK to use their cameras in trade when I was obviously a greasy thumbed slob. I sent it to canon. I might have tried it myself with the instructions I found here today, but it was a good excuse to buy a used back up body while I waited for my main body to come back and I have been happy to have my spare many times since. Every failure is an opportunity for improvement!