filter holder/system for wide angle/90mm lens on 4x5

**Bob Salomon** · 3-Sep-2015, 13:55

Originally Posted by xkaes

Sure, but you can test this -- if you happen to know how much swinging/tilting/shifting/rising you will do with the lens. With many wide-angle lenses their is little room for movements even without any filters! And with a pretty collapsed bellows you are physically limited to small movements anyway. My 47mm just barely covers 4x5 but I can't move much at infinity even with a recessed board due to the nearly completely collapsed bellows. My 105mm just barely covers 4x5 but I can't move much at infinity due to the small image circle. But I find I don't need, nor use, much movement with my very wide-angle lenses.

That is with your camera. But there are cameras with much more flexible bellows, there are cameras that can use recessed boards and there are cameras that accept a bag bellows. All of these can let you use as much movement as the lens allows the camera of your choice. In other words, themovementsare limited only by the bellows and the lens coverage on these cameras and not because of restrictions in the camera's design.

**xkaes** · 3-Sep-2015, 18:45

I ran some tests today to check things out for my own benefit, but others on this board might find it helpful. I know the orginal discussion was about 90mm lenses, but I did not use a 90mm lens. I decided not to use a 90mm lens because I don't have one. I have a Schnieder 47mm XL f5.6, Fujinon SWD 75mm f5.6 and a Fujinon NSW 105mm f5.6. Since the 47mm and 105mm have such small image circles, 166mm and 174mm respectively, I did not see the point. With the 47mm, I can move about 6mm, and with the 105mm about 10mm. On my cameras that's about all I can move due to the bellows restriction. With the 105mm, I can move more than 10mm, but get vignetting at that point without any filters.

So I opted to test my 75mm which has a much larger image circle -- 196mm -- so I can move about 25mm before I get vignetting without any filters. That's about all I would need anyway. Plus this 75mm lens has a flange focal length of 85mm on a bellows that collapses to 65mm. So there is plenty of room to move with this lens. I first tested the lens, focused at infinity, and did not see any vignetting with a 25mm rise. I then added a 67mm UV filter and 67-to-77mm step up ring. Again, there was no vignetting with a 25mm move. I then started adding filters. When I added two -- that makes more than 3 filters with the UV and step-up ring. Here I saw a tiny bit of vignetting at 25mm. If I needed to get to a 25mm move, I could always remove the UV filter. And if I didn't need a 25mm move, I could add at least one or two more filters -- a very unlikely scenario.

I then added the Cokin P adapter to the 67mm UV and step-up ring. I could not get close to a 25mm move before vignetting occurred. But I can still use the Cokin P as long as I don't need lots of movement. So a 90mm should work fine with either of these two approaches, assuming it has as wide an image circle.

Then just for kicks, I put on a #2 close-up filter. Since this shortens the focal length I had to refocus, shortening the bellows. With the UV filter, step up ring and #2 close-up filter, I saw a tiny bit of vignetting with a 25mm move. So this approach will improve my lens flexibility especially when I don't need much movement.

I have #1, #2, #4 and #10 77mm close-up lenses. They can be used singly or stacked. I did not purchase these to use as close-up lenses nor to shorten the focal length of my lenses. I got them to use as soft-focus lenses. If you remove the glass from a #1 Copal shutter and find or make an adapter to attach the close-up lens to the shutter, you end up with a very nice soft-focus lens -- on the cheap. The image is nice and bright and easy to focus. You can use it wide open for very soft effects or stop down for a sharper image. You need to figure out what the f-stops really are, but that it not too difficult. I have a Copal #1 to Leica adapter and use step-up rings to get to 77mm. Actually smaller Close-up filters will work just fine as well. The #10 is a 100mm lens on a 4x5 camera, for example -- pretty wide, actually. Stack a #1, #2, #4 and #10 together and you get a 60mm lens!

So I encourage anyone interested to go out and test your lenses. It's not only fun, but helpful.