How to clean a canon 35mm VF. any pitfalls?

H

hap

Well-known
Local time
8:50 AM
Joined
May 9, 2009
Messages
1,327
Irecently acquired the black tubular VF 35mm with parallax gizmo. I'd like to clean it up a little. Any issues or pitfalls of opening this up?

thanks
 
I have not stripped and cleaned the one you mention (either in 35mm or 28mm - these ones in chrome and black livery are both later versions). But I have stripped and cleaned the 35mm all chrome earlier version. It was some time ago and I do not recall of the details but my overall memory is that it was very straight forward. Unlike varifocal finders, I do not think there were any prisms or anything like that inside - just a couple (?) of glass elements. In that instance the front retaining ring simply unscrewed, allowing access to the metal 35mm framing "window" and the front element. After that there was not a hell of a lot to the internals as I recall it - no diopter mechanism or anything like that so the "guts" are very straight forward. I do not recall if I removed the rear element or if I just cleaned them in situ using an ear bud dampened with cleaner.

BTW the metal framing window should have a couple of metal lugs which engage with slots in the body to keep it properly aligned and unable to rotate out of alignment. I do recall that on mine the window seemed slightly out of alignment for some reason after I reassembled it but with a little fiddling it eventually came good. I feel sure I would have cleaned the optics with glass cleaner, then allowed them to dry thoroughly and then reassembled the unit.

I have a small collection of accessory viewfinders of various sorts and they are all a little prone to fogging but I do not think any have been so bad as to require more than a relatively light cleaning of the glass. On the other hand I have sometimes had extraordinary problems getting some haze off the internal elements of some lenses but that is more because lenses have helicoids, helicoids are lubricated and some lube types can out-gass or migrate onto the internal elements and become very difficult to remove over time when they have set in place. With that type of hazing I have had recent success treating the hazed elements with a hydrocarbon based dry cleaning fluid which dissolves the "gunk". Having said that, sometimes the haze in lenses is permanent because it has etched the elements' coatings and this then really cannot be treated.

Viewfinders seem not to suffer any of these more extreme hazing issues in my experience presumably due to the lack of lubricants in the mix, so any hazing is, in my experience, easier to deal with in most cases.
 
peterm1 said:
I have not stripped and cleaned the one you mention (either in 35mm or 28mm - these ones in chrome and black livery are both later versions). But I have stripped and cleaned the 35mm all chrome earlier version. It was some time ago and I do not recall of the details but my overall memory is that it was very straight forward. Unlike varifocal finders, I do not think there were any prisms or anything like that inside - just a couple (?) of glass elements. In that instance the front retaining ring simply unscrewed, allowing access to the metal 35mm framing "window" and the front element. After that there was not a hell of a lot to the internals as I recall it - no diopter mechanism or anything like that so the "guts" are very straight forward. I do not recall if I removed the rear element or if I just cleaned them in situ using an ear bud dampened with cleaner.

BTW the metal framing window should have a couple of metal lugs which engage with slots in the body to keep it properly aligned and unable to rotate out of alignment. I do recall that on mine the window seemed slightly out of alignment for some reason after I reassembled it but with a little fiddling it eventually came good. I feel sure I would have cleaned the optics with glass cleaner, then allowed them to dry thoroughly and then reassembled the unit.

I have a small collection of accessory viewfinders of various sorts and they are all a little prone to fogging but I do not think any have been so bad as to require more than a relatively light cleaning of the glass. On the other hand I have sometimes had extraordinary problems getting some haze off the internal elements of some lenses but that is more because lenses have helicoids, helicoids are lubricated and some lube types can out-gass or migrate onto the internal elements and become very difficult to remove over time when they have set in place. With that type of hazing I have had recent success treating the hazed elements with a hydrocarbon based dry cleaning fluid which dissolves the "gunk". Having said that, sometimes the haze in lenses is permanent because it has etched the elements' coatings and this then really cannot be treated.

Viewfinders seem not to suffer any of these more extreme hazing issues in my experience presumably due to the lack of lubricants in the mix, so any hazing is, in my experience, easier to deal with in most cases.
Click to expand...

hi Peter... I have removed the retaining ring in front but then decided to get expert advice going further. I suspect it is as straightforward as you predict. I intend to use lens cleaner on a "bud". I am interested in what sort of dry cleaning fluid brand do you use for lens haze.
 
I cleaned the chrome 28mm Canon finder that came with my Serenar 28mm lens, it was relatively easy. As always be very careful not to tighten retaining rings against the glass elements too much and risk cracking the glass.
 
You must log in or register to reply here.
Back
Top