Mirror Cleaning

jeffreaux2

Is there a good...safe way to do this?

Art Scott

I use my ZEISS lens clothes (prewetted type) and very gently "brush" in one direction across the mirror.....haven't had any streaks yet......knocking on wood (dogs head:D and window sill)..........

gryphonslair99

For me, unless it is causing focusing issues or just bugs the heck out of you too badly, and it can't be fixed with a gentle puff of air from a Rocket Blower, I would leave it alone. If it has to be cleaned I personally would take it somewhere to have it done. The mirror can easily be damaged necessitating a replacement.

pathfinder

It is a front surface mirror - the silver is on the top surface facing the pentaprism and is very delicate and very easily scratched or corrroded.

I might consider a camel's hair brush very gently. I would use not solutions on it at all.

If a camel's hair brush was not adequate, I would stop there, personally.

We use front surface mirrors in my office, and they have not been touched for over 30 years, except for a very occasional brushing with a very soft, fine brush.

I think using alcohol on a front surface mirror is asking for trouble, but that is just my opinion, apparently the astronomers do use isopropyl alcohol diluted with distilled water.

There is an interesting discussion of the topic here but the answers are less that totally satisfactory here as well.

Here is one that is more convincing from an optical lab - http://www.lhup.edu/~dsimanek/scenario/labman3/geninst.htm

The AOS Super Plus cleaning solution described on the Arkansas Sky Observatory sounds very convincing to me - reflecting telescopes have large front surface mirrors, which may or may not have a protective coating so astronomers will be very careful cleaning their front surface mirrors also.

Mirrors in the body of an SLR really have to be pretty dirty to have any viewing effect at all, and will not affect the image on the sensor at all. Are you sure the dirt isn't on your pentaprism or focusing screen?

Tango

i used my "hill method" kit once and was very very light with a hint of the solution.... and very very light with the stroke and all was fine. but after reading pathfinder i think i got lucky and i dont think i will push my luck a second time....

Mitchell

I was always told you should never attempt to clean a front surface mirror.

Maybe PF told me that years ago?

jeffreaux2

I cannot see it through the viewfinder, but got a spot of skin oil on it from the back of my knuckle while removing the focus screen....which was filthy. Im just wondering if leaving the spot on it is worse....or better than trying to clean it. I have the wipes Art mentioned....just scared to ruin the thing.

pathfinder

If it ain't broke, don't fix it has always been my motto.:D

I notice that the link from the Arkansas Astronmy group said the same thing about cleaning front surface mirrors. Unless it really needs it, do not do it.

I scratched,slightly, a mirror in a Mamiya-Sekor SLR years ago - and I thought I was being very careful at the time. I was a lot younger and braver then.

A front surface mirror is far more delicate than an anti-aliasing filter covering a silicon sensor.

I don't think the oil will hurt the mirror if you cannot see it through the viewfinder. Leave it for the next owner of your camera as you upgrade in the next year

pathfinder

Mitchell wrote:

I was always told you should never attempt to clean a front surface mirror.

Maybe PF told me that years ago?

Mitch, you're making me sound a lot older than I really am:D