Cleaning Bronica SQ A focusing screen... how?

[abr]

I just bought a used SQ A, and the focusing screen is grungy. I'd like to try to clean it up before resorting to buying a new one. Any ideas about what to use to clean it safely?

 

[DWThomas]

I haven't had occasion to clean mine, but I would probably start by popping the screen out and trying warm soapy water. I'm not sure I would try to do any wiping or scrubbing though, at least not on the "ground" side. If there's grease pencil type stuff, lighter fluid (naptha/mineral spirits) could probably be useful and is fairly benign as solvents go but usually effective on adhesive goo, marker pen ink and waxy/greasy stuff. "Wash, rinse and blow dry." Handle the screen by the edges, I believe the surface is pretty delicate.

 

[jime11]

I would not touch it!! The surface is DELICATE.
I have an ETRs that Bill Maxwell did his "Hi Lux" process on. I was considering selling my zoom lens before getting this done. It made all the difference in general brightness & ease of focusing.

http://www.mattclara.com/maxwell/index.html

 

[jime11]

Correction: he did the process on the focusing screen not the whole ETRs.

 

[wiltw]

As cautioned, DO NOT WIPE DRY!!! You can immerse the screen in water with dish detergent, rinse well under running tap water, THEN do final rinse with DISTILLED water and stand on end carefully and let air dry without touching the surface. Not using distilled water final rinse runs risk of junk or deposits of minerals from your water company and/or plumbing remaining on the screen.

 

[abr]

I would not touch it!! The surface is DELICATE.
I have an ETRs that Bill Maxwell did his "Hi Lux" process on. I was considering selling my zoom lens before getting this done. It made all the difference in general brightness & ease of focusing.

http://www.mattclara.com/maxwell/index.html

Thanks for the recommendation - I will give him a call. Can you give me a ballpark on what that ran you?

 

[jime11]

If I remember correctly it was about $100

http://photo.net/large-format-photography-forum/00AFok

 

[wiltw]

Just remember that all screen 'brightening' processes will alter the accuracy of metering prism finders.

 

[abr]

wiltw... true. However, not ever having tried one before, are you saying that the metered prisms are actually fairly reliable otherwise? I tend not to trust anything but my handheld meter. I'm intrigued by the possibility of not having to carry it everywhere, though.

 

[wiltw]

Metered prisms are every bit as good as any other reflected light meter in cameras. And they have similar foibles, like being fooled by subject reflectivity not 18% gray and scene averaging to something other than 18% gray.