Cleaning an HB Acute Matte D?

[bags27]

Is it even possible, let alone desirable?

I have an annoying what looks like a little water mark near the center, plus some very tiny black flecks (a black finder) seem caught around the Fresnel. I can certainly ignore this and probably should. But if anyone has a reliable method, I might be crazy enough to try it. Thanks!

 

[mshchem]

I would be very careful. I'm sure someone here will know. I wouldn't use anything liquid at all. Camels hair brush.

 

[Light Capture]

Handheld bulb dust blower is the safest.
Cover glass on top can be cleaned with slightly moist lens cleaning cloth. You have to be very careful not to get any liquid under the frame (some screens don't have the cover glass. So anyone reading who has a screen without top cover glass - don't clean those screens this way).

Other than that, the only thing safe for plastic surface is Pec pad. Haven't tried it with any liquids but it will dust it off if needed.

Third option is something I saw but never tried is Visible Dust Focusing screen cleaning swabs for (D)SLR's. Will probably try it at some point since I did use them on some smaller sensors and digital backs. They are quite expensive to use as they can be only used once per side.

In 99% of cases what you see that looks like a watermark stain isn't cleanable.

 

[campy51]

I generally use dishwasher soap and water and use my finger , rinse and pat dry on my Rolleiflex and others.

 

[OAPOli]

In principle you can open the metal frame and separate the cover glass from the screen to clean the mating surfaces. I've never done it. Opening the frame without scratching the screen seems tricky.

 

[itsdoable]

Hasselblad acute matte screens are 2 layers, the top layer is a glass (you can add/remove guideline marks on it with a fine grease pen) and the bottom is the acrylic acute matte surface, which is on the exposed bottom of the screen.

DO NOT use a liquid cleaner (or be extremely careful if you do!!!), as the liquid will wick between the layers and dry there, causing visible stains. The same is true for precipitation, don't let too much fall on the screen or it will wick and stain.

The screen can be disassembled for cleaning, but it is almost impossible to do this without leaving some marks.

My recommendation is - if the screen is still usable after cleaning with a blower brush - ie: you can focus easily and the stains/debris is not bothersome, then just use it as is. If it is really bad or bothersome, you can get some one to disassemble the screen and clean the panels (dish soap and water is what I use), with the understanding that it will probably sustain some marks (possibly some fine scratches on the screen, and marks near the edge). The top and bottom of the metal frame snaps apart/together. Care must be taken on the bottom layer which is not very scratch resistant.

 

[Sirius Glass]

Very carefully clean with a bulb air blower and a very soft brush. Then only if necessary clean the underside and replace exactly as it came out. If and only if necessary then clean with a lens cleaner as necessary using only minimal amount of lens cleaner.

 

[Slixtiesix]

Also be careful not to touch the underside of the screen, as you could damage it. I would leave the screen in the camera and just carefully clean the top glass with a brush and if this does not help, with a cloth and a little bit of lens cleaning fluid.

 

[bdial]

I don’t have any experience with Acute Matte screens, but my camel hair brush left faint marks on one of my standard screens. The brush was clean and I used what seemed like a light enough touch.

As others have said, be really careful, and only touch the plastic part of the screen if you can’t live with the speck. Otherwise, IME, you’re better off leaving it.

 

[bags27]

Thanks, all. I think I'll go very, very lightly on the surface with a blower. Maybe that's all that I need for now.

Through odd circumstances, I came into an unused one of these:

https://www.bhphotovideo.com/c/product/1218198-REG/hasselblad_3042264_focusing_screen_for_cfv_50c.html

I do have a Blad 50 c II, but just ballpark when I use the digital back on my 500 c/m. But maybe I'll put this on the 500 and just ignore the lines when I shoot film, which is most of the time.

 

[itsdoable]

Thanks, all. I think I'll go very, very lightly on the surface with a blower. Maybe that's all that I need for now.

Through odd circumstances, I came into an unused one of these:

https://www.bhphotovideo.com/c/product/1218198-REG/hasselblad_3042264_focusing_screen_for_cfv_50c.html

I do have a Blad 50 c II, but just ballpark when I use the digital back on my 500 c/m. But maybe I'll put this on the 500 and just ignore the lines when I shoot film, which is most of the time.

That screen has markings for a 36x48 sensor (cfv39/50), the 50c is a 33x44 sensor.

I've just cut cardboard or thin plastic masks that sit on top of the screen. A clear plastic mask works if you want to see the rest of the screen.

 

[bags27]

That screen has markings for a 36x48 sensor (cfv39/50), the 50c is a 33x44 sensor.

I've just cut cardboard or thin plastic masks that sit on top of the screen. A clear plastic mask works if you want to see the rest of the screen.

Thanks!
How does one get and put a clear plastic mask on?

 

[itsdoable]

Thanks!
How does one get and put a clear plastic mask on?

You just drop them on top of the screen, and slide the wlf or prism back on .
3D printed masks are available, for instance (https://www.ebay.com/itm/234564007279)

I cut clear ones out of a piece of clear PET food/bubble packaging