Cleaning Hasselblad Focusing Screens

[rob_martin5]

Not so much a question as simply sharing a very stupid thing I did

recently...

 

I bought a "new" 503CW on ebay, and it was nearly immaculate except

that the focusing screen was rather filthy--not scratched in any way-

-just dirty. It actually looked as though someone had sneezed on it

or something. I figured it would take a bit more than simply

blowing it off with a duster, and I'd read that these screens are

acrylic--not glass; so, lens cleaner would be a no-no. I decided to

very gently wash it under warm running water with mild soap. It

cleaned up quite nicely with no resulting scratches. The problem is

that I hadn't realized that these screens apparently consist of two

plates that are sandwiched together. Rinsing the screen under

running water resulted in water/moisture being trapped between these

plates. It's difficult for me to describe the appearance, but it

seems to be slowly clearing up. I did this several days ago, and

the adverse effect is all but gone now. I'm hoping it will

completely clear up, but it's been a slow process.

 

Dumb, dumb, dumb thing to have done, and I just thought I'd share it

so someone else doesn't try the same thing. It might have (and, may

still) cost me a new screen.

 

Rob

[paul_neuthaler]

Don't beat yourself up: be patient -- water evaporates!

[simon_platt1]

Rob

If the marks don't all disappear trying washing it again in distilled water (often aso sold as De-ionised water)This should dry completely clear as it will have no minerals in it.

 

Advice for anyone else in the future. A cotton bud damped with distilled water probably would have done the job better.

[cpj]

Stand it on EDGE, behind window glass, and where it can get some sunlight. (Glass filters

ultraviolet light) Don't let it get "hot" but a couple of hours ought to drive out the water

vapor that's trapped. It should be no problem unless you got some soap in there. If you

have soap stains, then the distilled water suggestion is the way to go.

 

For the future, there is a product out called "iKlear Apple Polish" which is sold in a pump-

misting spray bottle and has no harmful stuff in it. It is designed for computer screens and

especially Apple Computer flat panel displays found in their Powerbook portable

computers. It works great and I use it all the time on my "plastic" eyeglasses as well as on

the computer. It comes with a very fine, lint-free wiping cloth about 12 x 12 inches. Use

only a very small amount. Check it out at www.KlearScreen.com

 

PETE

[chenwah_lee]

I have the same experience like Rob but I later found out that you can take the pair of plates out of the metal frame which holds the two plates together. Then you can clean each plate separately. Of course you need to put them back together in it's original sequence and direction otherwise focusing will not be accurate.

Happy New Year.

[rob_martin5]

Interesting, Chenwah...I hadn't considered taking such a risk (e.g., deforming the frame structure, introducing dust between the plates, etc.). However, at this point the odd effects continue to linger with no apparent signs of further improvement. So, I just separated the plates, and I'm going to attempt to wash them with distilled water and see what happens.

 

Rob

[q.g._de_bakker]

But be careful!<br>You know how much these thingies cost. And while the plastic bit is fairly 'safe', the glass is rather thin. The frame will never fit together as snug as it did originally, but that may be just a matter of cosmetics. Unless it is just that bit too much out of shape. Then it will be a matter if out-of-focus.

[rob_martin5]

Phew...well, I think I got it back together pretty well enough; and, it does look a whole lot better. In fact, aside from one tiny speck of dust I allowed to get between the plates, it looks as good as new. After so much handling of each piece, though, I'm only 99% sure I reassembled it correctly. The etched surface does go on the outside (facing downward, toward the mirror), right? I couldn't tell a difference in surfaces of the thin plate, but I think I replaced it as it was originally. I know it lies on top (as the screen sets in the camera). The camera appears to focus normally, although, I'm new to MF and don't have much of a point of reference. I'm finding it generally difficult to focus anyway but figure this just takes a bit of practice/experience.

 

Rob

[q.g._de_bakker]

Rob,<br><br>It certainly sounds like you got it the right way round, yes.