Dust on SLR Mirror

[Canis Vulpes]

We all know we may need to remove dust from a DSLR sensor but what do you do if dust or larger particles are found on the mirror and seen in viewfinder?

[Ian]

For any dust removal I remove lens, lock up mirror and very carefully put the vacuum nozzleto the lens housing for a few seconds and this seems to work fine.

Ian

[miketoll]

If it stays on the mirror and does not transfer to the sensor then it has no effect other than being annoying. I had this problem with my film SLR and in my ignorance just wiped the marks off with a lens cleaning cloth with no harm done. I would be a little more gentle now but if it annoys (which it would me) then I see no reason not to clean the mirror like a sensor. Marks can also become apparant on the screen that is above the mirror that the mirror comes up against when it flips up during an exposure. These marks will be more in focus than the ones on the mirror itself and are more likely I would have thought to be the ones you are seeing. Again they will not effect the photo and just carefully remove.

[yelvertoft]

I used to use a blower brush, but found the silvering to be very fragile. The silvering is on the front surface of an SLR mirror, not onthe back, protected by a layer of glass. Since making a problem much worse on a film SLR, I've given the body to a repair shop whenever I've needed dust removing.

I was very saddened to see my local camera repair shop had closed down recently. I don't know who I'll use next time I need a spruce up.

[miketoll]

Originally Posted by yelvertoft

I used to use a blower brush, but found the silvering to be very fragile. The silvering is on the front surface of an SLR mirror, not onthe back, protected by a layer of glass. Since making a problem much worse on a film SLR, I've given the body to a repair shop whenever I've needed dust removing.

I was very saddened to see my local camera repair shop had closed down recently. I don't know who I'll use next time I need a spruce up.

Guess I was really lucky but mainly its been the fresnel screen I've had to clean which is probably a bit more robust than the mirror.

[Don Hoey]

Duncan has said it about the silvering on the mirror. VERY VERY delicate. The most I have ever done is to sweep with a very fine brush. I would NOT advise using any form of liquid cleaning.

I think you are more likely to find dust that is visible in the viewfinder to be on the focussing screen itself. If the spots you see are sharp then they are on the screen and not the mirror. Just dirtied my F2 to prove accuracy of that statement. ( lunatic )
The fresnal part is very finely etched onto the underside and can attract dust. The top of the screen is a polished surface.

On the older F2 and F3 cameras with a removeable/interchangeable viewfinder dust on the screen was a regular hazard. No worries about changing lenses in dodgy conditions in those days, as the screens were removable and could be cleaned with a blower.

So first thing is to determine if dust is on the screen. Fairly sharp or sharp when looking through viewfinder. If looking at the mirror and you cannot grow spuds on it then most likely on the screen.

Don

[Christine]

A link on this Forum to Intemos.com proved very helful.They sell swabs and fluid which are very east to use,they provide very easy directions as to how to use.I clean all my sensors when they show lots of dark spots.I used to send my cams off to be cleaned,but if I can clean them,anyone can.
I did try with a blower,but made things worse.So now do a wipe clean with the swabs,and yes,it does work.

[yelvertoft]

Originally Posted by Don Hoey

On the older F2 and F3 cameras with a removeable/interchangeable viewfinder dust on the screen was a regular hazard. No worries about changing lenses in dodgy conditions in those days, as the screens were removable and could be cleaned with a blower.
Don

Of course, if you've got a Pentax dSLR, you still can change the focusing screens.

[Canis Vulpes]

Focus screens can be changed on D1 and D2 series DSLR's from Nikon. I have a large particle on the focus screen but thats no problem, I can remove and clean or employ a spec grabber. When cleaning the sensor I noticed dust on mirror also.

I recently purchased a used Nikon D2Hs as a second body, it remains a second body so I after reading advise here I am more inclined to leave the little dust on the mirror but remove the particle on focus screen.

Should it require service in future I shall stipulate its is cleaned, properly.

[sassan]

Apart from delicate coating of mirror, I never trust myself to play around a moving part in camera or for that mater in most compact electronic devices.
No wonder my solution for mirror dust is "To tolerate".