Posted by Peter Cross on October 24, 2011 at 12:37 AM
Towards the end of the day yesterday, I noticed a spot in my viewfinder. I quickly checked my lens - nothing. Looked at the viewfinder and that seemed okay. Looked at several photos and no spot on them - whew!. When I got home, I did a thorough cleaning of the lens, filters, the viewfinder, etc. and still a spot. As this is not showing up on the photos, the only thing I can think of is that it is on the flip up mirror. If so, that should be much easier to clean than if it was actually on the sensor. Any recommendations as the the best way to remove it, if agreement as to the location? The only weird thing is that it is a perfectly round and perfect in color black spot. I would have thought dirt or whatever would be more irregular in shape as well as transparency. Camera is a Canon 60D. Thanks for any feedback on this.
Peter
Posted by Mark Seaver on October 24, 2011 at 10:33 AM
Peter, it might also be on the focus screen (at the top of the mirror box). My first choice for removal either from the focus screen or the mirror would be strong puffs of air while holding the camera body upside down. (I use a Rocket squeeze bulb.) If that doesn't work a very gentle wipe with a soft, lint free cloth (well washed cotton or microfiber or if you can find it lens tissue). Fold the wipe to make a flat edge, hold it away from the edge, and gently swipe the optics. If neither of those works, you need to look into liquid cleaners where the type of coating (if there is any) determines what liquid should be used.
Posted by RL Potts on October 24, 2011 at 10:59 AM
Try the puff method, but beyond that, you might be better off just putting up with the spot. My experience is that going after a spot on the mirror disturbs the film of crud residing there and makes you want to clean the whole thing which is a bad idea because some of these mirrors are very, very soft and prone to scratching.
Don't touch the mirror with anything other than compressed air--it will scatch in a heartbeat! Also, be very careful with the focus screen (ground glass) they will also scratch easily. If compressed air doesn't eliminate the spot, I'd just leave it, since it's not affecting your images.
Discussion
3 repliesPeter
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