Help! Filter stuck on Hasselblad 80

[fong]

Hi, long-time lurker, first-time poster here.

I bought a used Hasselblad 503CW + 80 CF lens last year... unfortunately, the lens has a Hasselblad UV filter mounted on it that seems to be totally stuck. I can turn it a bit in each direction (about 3 cm at most) but it never quite keeps going and eventually "grinds" to a stop. I've tried a few ways to remove it (putting it in the freezer for a few minutes, using rubber gloves to twist the filter off), but to no avail. Is there anything else I can try myself before I give up and send it to a repair person?

Thanks!

[Thanasis]

Hi there fong,

Have you been able to get this filter on and off before?
It sounds like it *should* come off especially after it travels 3 cm. Are you aware that it is a bayonet style filter and not a screw thread? It should twist in one direction (for about 3cm as you have described) and then feel loose enough to pull off. If it doesnt feel lose, DO NO FORCE IT. Try to wiggle it off.

Hope this helps.
Regards,
Thanasis

PS: Welcome to APUG

[fong]

Hey Thanasis, thanks for the tip about the filter! :o I received the lens like this (with the filter on it), so no, I've never actually had it removed or mounted it myself before. It certainly feels a lot tighter than it should when I try to turn it... I'm not sure what to make of it. I definitely cannot wiggle it at all, the only way I can get the filter to budge (somewhat) is to force it (a little). Based on everything I've read thus far, I've refrained from trying to apply any lubrication.

If worse comes to worse, is it possible for a technician to cut the filter off without damaging the lens? (That would obviously be a last-resort thing, but at this point, I'd like to explore my options since I'd like to eventually try some IR photography on the 'blad.)

[Bruce Osgood]

Welcome to APUG.

Cold is the wrong temperature for such an operation... it contracts and binds the two pieces. Warmth is the better temperature. I have been successful separating filters from lenses by placing the palm of my hand over the surface of the filter and letting the warmth penetrate for a couple of minutes. Keeping my palm in position exert equal pressure around the edges by gently pushing down and turning off. Doesn't always work though.

They also sell a wrench for removing jammed filters. It fits around the circumference of the filter and with its' handle the filter can be wrenched off.

Hope this helps.

[fong]

One other thing I should probably mention: it takes quite a bit of effort for me to move the filter at all. When it does move, it's very tight and definitely feels like some metal-to-metal contact is happening (almost gritty). There is no obvious evidence that the filter was somehow mis-mounted or that there is dirt in there.

I didn't get a manual with the camera — this probably sounds dumb, but how exactly does one remove a Hasselblad filter? I'm used to the screw-in type and have never dealt with a bayonet mount filter before. I see some "threads" on the front of the filter... can I use those as a guide as to when I should expect to be able to wiggle the filter off?

Thanks again!

[bobwysiwyg]

I've had to remove filters with a filter wrench when they are just jammed on too tight and they work great. I would be careful on this one though, sounds like, with the small amount of movement then stops, that you could be talking about stripped threads.

[Photo Engineer]

You cannot use a filter wrench with a bayonet mount filter!

PE

[Thanasis]

I've had to remove filters with a filter wrench when they are just jammed on too tight and they work great. I would be careful on this one though, sounds like, with the small amount of movement then stops, that you could be talking about stripped threads.

There are no threads. It is a bayonet type mount.

[Thanasis]

If worse comes to worse, is it possible for a technician to cut the filter off without damaging the lens? (That would obviously be a last-resort thing, but at this point, I'd like to explore my options since I'd like to eventually try some IR photography on the 'blad.)

Cutting the filter off sounds very drastic (I've never heard of it being done, by the way) and I can be fairly confident in saying that your lens will not survive the operation unscathed. Try warmer temerature. The grittiness you observe is fairly common to bayonet filters. Unless it sounds like its really wrecking the bayonet mount its probably nothing to worry about. I would try using warmer temp to get things to expand and possibly loosen up.

[c6h6o3]

I would take it to an authorized repair person to have it removed. It sounds like the camera was dropped with the filter mounted and one of the little dovetails was crimped over the corresonding lug on the filter.

I once had to have a Bay 50 lens shade cut off of my 250mm Sonnar. I had the camera on a tripod with a Manfrotto quick release head on it and slung it over my shoulder. A tree branch caught the release and the camera went straight down and hit the concrete square on the lens shade. It wouldn't budge. The camera and lens were fine. Those things sure are built well. Nevertheless, I use it only on a Ries tripod now.