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! 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.

 

[fong]

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.

I think I had read somewhere that cutting the filter off was a possibility, if filter wrenches and the "usual" techniques don't work, but I definitely cannot vouch for that (nor do I remember exactly where I read it).

How warm do you think I should get it to? It's currently late summer here in Montreal, with the daytime temperature ranging between 20 to 30 Celsius. I shudder at the thought of putting my lens in the oven to get it even warmer!

 

[fong]

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 was afraid of that possibility, although I must say that there is no evidence that the lens or camera were ever dropped, and I don't see any evidence of impact marks on the lens or the filter.

I believe that David Odess has a good reputation for all things Hasselblad, but I was wondering if anyone knows of someone in Montreal (or Canada, for that matter) who might be able to handle such a repair?

 

[MattKing]

I was wondering if anyone knows of someone in Montreal (or Canada, for that matter) who might be able to handle such a repair?

Does anyone in Montreal have Hassleblad equipment for rent? If there is anyone, they will know who to send it to (or be able to do it themselves).

Matt

 

[bdial]

With the lens facing away from you, it tightens to the left, loosens to the right.
I face this situation regularly, as my 80 has a damaged front. The fit of Hasselblad filters is very precise, it's not unlikely that either your filter, or the lens has some damage. Another possiblity is some corrosion if the filter has been in place for a long time. I would try applying some penetrating lubricant to the seam between the lens and the filter with a tiny brush, then give it some time to work it's way in. Don't use more than a couple drops worth, if you have a spotting brush you can sacrafice that would be ideal.

The filter turns about an inch from fully-locked to loose, but the point that you can lift the filter off starts about 6 or 8 mm shy of where it stops when you turn it fully to the right. At the full right position, the bayonet's catch again slightly so you need to be just shy of that point.

Once you can get it to turn an amount that seems suffcient, then work at pulling the filter straight off. Sliding a knife edge into the seam in a few places around the circumference may help as a last resort. Don't twist or pry with it, the thinner the better. I used an X-acto blade (Very carefully!!), it can only go in by less than a mm or so.

If you have another filter, you can use it on the front to get a better idea of how everything works, just be careful in fitting it. If the lens ring is damaged, it can distort the aluminum ring of the filter that's there, and transmit the tight fit.

I've not dealt with David Odess personally, yet, but I understand he is pretty good about giving advice, try calling or emailing him for some pointers, or references to someone around Montreal.

Barry

 

[bobwysiwyg]

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

Oops, missed that.

 

[fong]

Barry,

Thanks for the detailed tips on removing the filter! Although I have not yet tried the penetrating lubricant (and I have to admit I'm reluctant to screw things up even more than they seem to be), the filter still will not budge much, so I've sent David Odess an email... hopefully he can provide some insight!

 

[John Koehrer]

Keep the lube away from the camera! AWAY FROM THE CAMERA!
If the filter turns 3CM it should lift off. See above "turns about an inch".
I agree about a thin knife edge at the seam between filter & lens & gently pry upwards. Use something like an X-Acto knife. I'd suggest also that you do the prying at several places around the circumference. Just inserting the edge of the blade will probably be enough.
If it feels gritty, I'd give it a good cleaning once you get the filter off. The way the filter & retaining ring are made there should be NO gritty feeling as you rotate the filter, they should be buttery smooth. If they're not something has been introduced into the joint(sand,grit) it really doesn't take much

 

[fong]

Just received an email from David Odess regarding my problem.. To sum up, he recommends no lubrication whatsoever and that perhaps one of the filter mounts is damaged (therefore, neither heat nor cold will help in this particular situation).

He also recommended taking the lens to a repair shop where they could try a filter wrench to remove the filter and, failing that, cutting the filter off. He said this would be a last-resort option and can indeed be done without harming the lens.

So, kind of a good-news/bad-news scenario. Considering filter wrenches are fairly cheap, maybe I'll buy one this week and try wrenching the filter loose myself.

 

[fong]

..also wondering if anyone knows of a good repair shop in Montreal. There are several camera shops here, but I've never had to rely on any of them for repairs before.

 

[Photo Engineer]

See previous posts on filter wrenches. They often can fail to perform properly on non-screw threaded filters. The tendancy is to turn too far and harm either the filter or lens.

PE

 

[Andrew Moxom]

Before you try penetrating lubricant, (I'd advise against that as well!) try using a rubber glove and or a jam jar turning mat that helps get a better grip on the filter edge, but do not grab it by it's side, place the camera lens down on the matt/glove and apply pressure to it that way rather than distorting the edge by gripping it on the sides. Then rotate the lens. See if that moves it.