B&W Filter Concern with Nikor 90mm SWgreenspun.com : LUSENET : Large format photography : One Thread
Relating to the Super Symmar 110 XL thread, should I be concerned with scratching my Nikor 90mm SW lens with my B&W filters. I have only the regular ones (i.e., not the ones made for wide field lenses). Any comments or suggestions would be greatly appreciated.
Thanks in advance,
-- Thomas W Earle (email@example.com), March 03, 2000
I don't own this lens however, the instruction manual that comes with Nikkor LF lenses advises that caution is needed to avoid scratching the lens surface when usng screw-in filters particularily with the SW 65, SW 75, SW 120, SW 150, and W 210. As you can see the SW 90 is not mentioned. It can be hard to tell if the filter glass is contacting the front element. If you're concerned that it is then I would suggest a change, either to a extra wide filter or some combination of step up ring and larger filter.
I did own the SW 120 and do own the W 210 and used/use regular B+W filters with no problems.
-- Mark Windom (firstname.lastname@example.org), March 03, 2000.
I have not yet used my B+W Black and white screw in filters on my Nikon 150SW wide angle lens, but was more than a little concerned when I read your question. I did not see any literature on this subject when I purchased the lens and after carefull evaluation of the proximity of the low mounting position of the inside glass surface in the filter mount and the curvature of the outer lens surface, there is no question of the impending danger of the two surfaces making contact. It may be possible to mitigate this by only screwing the filter in enough to bearly engage the threads, but it is defilately not worth the chance to adversely affect a very expensive but versatile lens.
A spacer ring of some sort is now probably in order. Thanks for bringing this subject to my attention.
-- Michael Kadillak (email@example.com), March 03, 2000.
Here is how I (hopefully safely) test whether a filter will contact the front element of a lens: 1) clean all dust off of the front element, 2) orient lens facing up, 3) cut a piece of soft lens tissue to cover most of the glass but not the front threads, 4) SLOWLY screw on the filter, observing whether it contacts the lens tissue. When the filter is fully screwed on, if the lens tissue is loose or only lightly touched by the filter, then it would seem safe to use the filter.
-- Michael Briggs (MichaelBriggs@earthlink.net), March 03, 2000.
Thomas: I think Michael Briggs has the right solution, but IMHO I would use a thicker piece of paper to be on the safe side. You would also need to check every filter you plan to use on that lens. Not all of them would have the same thread depth or the same filter thickness. You have a good and expensive lens and it would seem that it would be worth while to test and keep seperate a set of filters that you know is safe with the lens. Another option is to put an adapter ring permanently on the lens and use size larger filters. It makes you wonder if the folks who design lenses ever make a photo with them. That is really stupid engineering on the part of Nikon and Schnieder and anyone else who makes lenses that can be ruined by filters. A lens barrel 1/16th of an inch longer would solve the problem. Good shooting, Doug.
-- Doug Paramore (firstname.lastname@example.org), March 03, 2000.
I own the 110xl and I use a step-up ring from 67mm-77mm to be on the safe side!! Without this even "slim" filters would touch the front element. The 75mm Nikon suffers from the same problem, and it would seem that most wide-angle lenses have far too small a pitch on the screw thread. Nikon do warn of this but why not supply the lens with a step-up ring in the first place, after all these lenses are not cheap. As a matter of interest the rear of the 110XL taks 52mm filters and the surface of the filter is well clear of the rear element. Regards Paul
-- Paul Owen (email@example.com), March 04, 2000.