jblazar Loc: Sunnyvale, CA

I just got a new Canon 5d Mk IV. I was changing lenses yesterday and happened to look at the mirror. It had a dust particle on it, so I blew it off with the torpedo blower (?). At the same time, I noticed one prominent line about 1 cm long toward the bottom of the mirror and a couple of smaller lines close by. I'm assuming that these should not be there. Should I try to clean them off? By the way, I've never touched the mirror, never tried to clean it, etc. So I don't see how I could have gotten those lines there by anything that I've done.

Thanks for your help.

DeanS Loc: Capital City area of North Carolina

Suggest you contact Canon direct. Best source for info/solution is with manufacturer. I have always been satisfied with my discussions with Canon techies.

jerryc41 Loc: Catskill Mts of NY

When you spend that much money on a good camera, you don't want it to arrive with scratches, inside or out. Can you see the scratches when you look through the viewfinder? All the mirror does is project the image from the lens into the viewfinder. The photo will be unaffected.

photoman022 Loc: Manchester CT USA

Take a number of photos to be sure there's nothing wrong with the sensor (be sure to enlarge them in post processing).

leftj Loc: Texas

Do you see the lines when you look through the viewfinder? If not probably not an issue. The other consideration is that since it's a new camera under warranty you might want to get it checked out.

amfoto1 Loc: San Jose, Calif. USA

I don't have a 5DIV (yet), but most Canon have semi-transparent mirrors, to allow some light to pass through to meter or AF sensors located behind the mirror. It might be that the "lines" you are seeing are actually supposed to be there. Or it could just be that some hairs or something settled onto the mirror when you used the blower.

My recommendation.... DON'T TRY TO CLEAN IT with anything more than a gentle puff of air from a bulb blower.

First, that mirror is front-surfaced with vaporized aluminum. It's easily damaged by improper cleaning. If it gets damaged, the repair will be costly and not covered by warranty.



Second, taking photos will prove nothing, so would just be a waste of time. Anything on the mirror makes no difference what-so-ever... it's just a minor nuisance if it's visible in the viewfinder (and there's nearly always something on those mirrors, if you look closely enough... cameras are not built in, kept in or used in a "clean room"). Anything on the mirror absolutely WILL NOT show up in your images... unless it somehow manages to migrate off the mirror, past the closed shutter, settle onto the image sensor and is able to adhere there so that the self-cleaning sensor isn't able to shake it off. You may not even be able to see small things on the mirror when looking through the viewfinder (which is much more relevant than peering into the front of the camera with the lens off). If large enough to be seen, things on the mirror will appear out of focus and blurry in the viewfinder (things on the focus screen, also delicate and should be left alone, will appear more sharply in focus).

I recommend you just leave it alone. Sometime in the future with normal use the image sensor will need a cleaning. You'll see spots on your images. Have the image sensor cleaning done professionally and properly, along with cleaning the mirror and focus screen at the same time if it's still needed. In the meantime, just ignore it, since it doesn't effect the images you make with the camera.

crphoto8 Loc: Anaheim, California

Get in touch with Canon support. You said the camera is new, so it should be under warranty. Is there a Canon service center nearby? If yes, take the camera there.

bdk Loc: Sanibel Fl.

I would have someone look at it for you BUT dirt on a mirror has nothing to do with your photos. The mirror flips up or down or out of the way when the photo is taken. Its only job is so u can see what the camera will see when u hit the shutter button.

CO

Do you see the lines when you're looking through the viewfinder? If so, it's likely that it's dust or a fiber on the focusing screen. When you have the lens off you will see a rectangular plate at the top of the mirror box. That's the focusing screen. Get a filtered blower and blow some puffs of air at it. I got the Koh Global Hepa Jet Air II filtered blower.
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bluezzzzz Loc: Stamping Ground, KY

I just looked at my 5DMk4 mirror and it has lines like you described. Don't know what they do but they are obviously a manufactured part of the Canon mirror design or they wouldn't be there.

Whatever you do, please don't try to clean them off!

Marshall Smith