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mantarays
18-Feb-2008, 23:37
Hello,
I was wondering if any lens would allow
the entire circle to be exposed.
After viewing Emmit Gowin's work I became
inspired by the circle effect.
With an 8x10 it seems obvious but I do not understand how to
do it with a 4x5.

thanks in advance,
conor

Nick_3536
18-Feb-2008, 23:57
Use a lens aimed at 2x3. Just hope it's circle of lumination is small enough. Unless you want fuzzy edges.

Chuck Pere
19-Feb-2008, 05:47
Use a lens shade to cut coverage off?

Michael Graves
19-Feb-2008, 06:46
I once shot a series of photographs of an old church using that effect. I took a 135mm lens from my Mamiya TLR, removed the lens and shutter assembly from the Mamiya lensboard and mounted it onto a Speed Graphic lensboard. Perfect circle, really sharp from the center to about a 3" circe, then drops off rapidly.

Leonard Evens
19-Feb-2008, 08:23
Of course, it isn't the lens; it is the camera. The issue is whether or not the image circle of the lens is smaller than the smaller dimension of the film frame. Normal 4 x 5 lens are naturally designed to cover the 4 x 5 frame, so you would have to choose a lens with smaller coverage or use one of the tricks suggested above. Alternately, you could scan and use a photoeditor to manipulate the image. It wouldn't require much to simulate an image circle effect.

mantarays
27-Feb-2008, 13:29
I saw a post on Photo.net taking about
a VOIGTLÄNDER SKOPAR 4.5/ 10.5cm barrell lens.
When looking into the lens coverage, i noticed it had a 100mm lens coverage.
Does that mean 100mm of shap image or is that the cut off?
100mm is just under 4in.

Would this serve my purpose?

thanks in advance

-conor-

Peter K
27-Feb-2008, 14:29
Depend on your LF camera you can use an adapter-ring for 35mm lenses mounted on a recessed lens board. 35mm lenses have the image circle you are looking for.

mantarays
27-Feb-2008, 14:41
The adaptor sounds like a great idea.
I have/will have a B&J field camera.
Does anyone know of a Leica adaptor?
I have a Leicaflex SL. I use a 35mm.
With the equipment I have does this
sound like a probable option for me?
(sorry for all the questions but I
am just getting into this and I haven't heard
of such an adaptor)

-conor-

Peter K
27-Feb-2008, 15:44
There where adapter rings aviable to use Leicaflex lenses with other cameras. I've tried my Nikkor lenses mounted on a Kardan-Bi together with a WW bellows to measure the image circles. With the same adapter and a distance ring I can use the Nikon camera with LF lenses.

Emmanuel BIGLER
28-Feb-2008, 01:35
I was wondering if any lens would allow the entire circle to be exposed.

You can have a look at this article by Gilles Barbier (in French but the images speak a universal language) about a home-made wide-angle 5x7" camera fitted with a wide-angle lens, the good ol' 6.8-90mm angulon-not-super that does ... not cover the format.
http://www.galerie-photo.com/barbier-hybis-90.html

Ole Tjugen
28-Feb-2008, 02:29
But you won't get a circular image from a 90mm Angulon on 5x7"...

Search for my name and "Angulon", and you shold find a link to my 90mm Angulon shootout, on 13x18cm (5x7") film. I'm on a work computer with limited access at the moment, so you'll have to find it yourself. :)

The Voigtländer Skopar is essentially a Tessar, which cuts off rather "sloppily": The image degrades a lot before it physically vignettes. A 75mm or 80mm Tessar/Xenar/Skopar might give a circular image on 4x5" film, a 100mm or 105mm I believe not.

One possibility in the "barrel lens range" is the Leitz 90mm f:4 Elmar. Remove the rear focussing tube (it unscrews easily), and you're left with a fine little 90mm Tessar-derivative lens. :)

mantarays
28-Feb-2008, 10:29
So do you think the
Schneider Xenotar f 2.8/80 mm lens
would give a crisp circle?

by the way, thanks for the link and the advice,
i appriciate it.

Peter K
28-Feb-2008, 11:14
There is another solution for your "problem": mount a black cardbord with a round cutout from about 4 inches in a distance from about one inch to the groundglass in your camera and you can use any lens.

Ole Tjugen
29-Feb-2008, 00:35
So do you think the Schneider Xenotar f 2.8/80 mm lens would give a crisp circle?

If the Xenotar "cuts" as sharply as the very similar Zeiss Planar, it should give a nice sharp circular image with a crisp edge. :)