What size centre filter for 65mm F8 SA

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I have just bought a 65mm F8 SA and a centre filter (schneider centre filter III). The lens is a 49mm filter thread but the centre filter delivered with it is a 65mm filter. They werent sold as a pair but I asked for a centre filter for the lens and both were bought at the same time. Question is - is this right ? I would have to buy a 49-65 stepping ring to be able to fit the filter to the lens but I would have thought that centre filters were matched to a specific lens and that I needed one with a 49mm filter thread.

Any help would be appreciated



-- David Tolcher (davidjt@btinternet.com), November 28, 2001


I was surprised to learn recently that Hoya make, or at least, once made, centre filters, and I snapped up a 72mm version to prove it. Very nice, all multi-coated and everything.
Sorry, that was beside the point.
I'm guessing that no-one makes a centre filter in a 49mm size, and that 65mm (weird filter size or what?) is the smallest option. There was a shallow hood made to fit the 65mm SA, and the filter is probably designed to fit into that.
A stepping ring won't do you much good, since the filter needs to nearly fill the angle of view of the lens to be effective.

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 28, 2001.

To work properly you need a center filter that fits directly.

-- Bob Salomon (bob@hpmarketingcorp.com), November 28, 2001.

I've just realised that the filter size you've been sold is the same diameter as the focal length of the lens. Did some idiot salesman think that you needed a 65mm filter to fit a 65mm lens??? Nah! Nobody's that stupid. Are they?

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 28, 2001.

Thanks for the responses. The filter was for 65 and 75mm lens rather than a dumb salesman - good thought - brightened my day :-). I'll phone the shop and ask.

I cant see how a 65mm filter would work properly on a 49mm filter thread.

-- David Tolcher (davidjt@btinternet.com), November 28, 2001.

Actually a 65mm filter on a 49mm thread would be about right. All center filters are wide-angle designs with the male thread being smaller than the female thread. Mine start out at 67mm and end up at 86mm - the glass will mate with the 86mm side - this prevents vignetting. A "proper" center filter with a 49mm male thread will have a female thread of ~62-67mm. Yours should have two different thread sizes. Try Schneider's site to see if a manufacturer's filter is available.

-- Wayne DeWitt (wdewitt@snip.net), November 28, 2001.

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