[tibbitts]

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I've had various size Cokin (brand) adapter rings for decades, but for the first time the 77mm one bent recently. I store them the same way I always have, in the holders (I have one holder, in this case a since-filter holder, for each ring, so I don't have to move them between holders.) Has anybody else experienced this problem? I have found some instances in searching, but wondered if it's common, since it's never happened to me before. Has anyone successful fixed a bent ring? I fiddled with trying to bend it back but it has to be very precise and I could never get it flat enough for the threads to work again. Has anyone had better luck with any other brand of adapter ring? I imagine the problem would be even worse with an 82mm size.

[Ian Stuart Forsyth]

Never

[tibbitts]

Never

It hadn't happened to me either but I've only had a 77mm for about 8 years. Before that I had a 72 (still do) and that's significantly more difficult to bend. I really wonder what I did wrong, since I don't want the same thing to happen again. I know I could upgrade to 100mm to prevent the problem but that's a big jump in size and price for all the pieces involved.

The aluminum flexes a certain amount and bounces back (which makes flattening the ring so difficult), but also bends easily when it flexes past a certain point. I imagine it's much worse with an 82mm ring.

[35mmfilmfan]

Why not just replace it ?

77mm Adapter Ring Connector for Cokin P Series filter holder and camera Lens | eBay

[tibbitts]

Why not just replace it ?

77mm Adapter Ring Connector for Cokin P Series filter holder and camera Lens | eBay

I already did, the replacement from ebay arrived yesterday and works fine. The problem is that whatever I did to bend it could happen again, since I don't know what I did wrong/different and therefore can't prevent it. And you can't just replace one when you're traveling. A lot of people just hold the filters but I don't have much luck with that - it just scratches the filters and with a 10mm lens you've got a good chance of getting finger or the edge of the filter in your images, especially when you're doing 5 or 10sec or longer exposures.

[35mmfilmfan]

Don't know if this is feasible, but could you keep the holders permanently attached to the lens which they fit, if you have sufficient clearance in the camera bag ?

[tibbitts]

Don't know if this is feasible, but could you keep the holders permanently attached to the lens which they fit, if you have sufficient clearance in the camera bag ?

That would be a good idea except that to store the lenses in my bag I need to reverse the bayonet hoods, and that won't work with the adapter ring on.

[rjobin]

I find with the 77mm Cokin Adapter ring for the P Series Holder, the holder rotates easily, rather than staying stationary, making it difficult to use my circular Polarizing filter. Any ideas why this is? Can this be fixed?

[tibbitts]

I find with the 77mm Cokin Adapter ring for the P Series Holder, the holder rotates easily, rather than staying stationary, making it difficult to use my circular Polarizing filter. Any ideas why this is? Can this be fixed?

You mean the polarizer rotates and the adapter with it, I assume. Yes it is difficult to use a holder with a polarizer for that reason, but it's not unique to any particular sizes. It's worse with a thin polarizer like the one I have. I don't think there is a good solution.