Rodenstock Imagon 360mm in a Compound shutter

[philippe_metayer]

First of all, thank you for your answers to my original question.

Now, I am not sure if I got this one right so correct me if I am

wrong.

I understand that the Imagon 360mm barrel lens will cover 8X10 and

allow camera movements.

So will an Imagon 360mm in a Packard shutter.

But specifically, will an Imagon 360mm lens in a Compound shutter

cover 8X10 without or with some camera movements?

I am asking because I would like to work with the 8X10 format but

only if I can use this particular lens in the Compound shutter. I

plan to shoot only on Polaroid film and I absolutely need a shutter

that gives me accurate speeds in the range of 1 sec. to 1/50 sec.

I have just purchased this particular lens/shutter combination but

before I invest in an 8X10 camera, I would like to make sure that it

will cover 8X10.

This lens came with the 3 discs and the previous owner marked the

f/stops on the lens so it can be used accurately without the discs.

I also purchased this same lens without a shutter and I had the S.K.

Grimes factory install a brand new Packard shutter. This was before I

purchased the one in the Compound shutter. And I will put the Packard

one up for sale if the Compound one covers 8X10.

Thank you for reading and thank you for your answers.

[john_shriver]

Make a "view camera" out of a cardboard box, with a peice of paper as a focusing screen. That will let you test the image circle. With all three of the lenses.

 

But, a shutter should not change the speed of a lens, so long as it has an even reasonably large shutter opening. Put the shutter on T, measure the size of the "hole". Measure the size of the iris at "wide open" on the barrel lens. So long as the shutter hole is as large or larger, you're OK.

[michael_briggs2]

<p>Seth Broder has posted scans of two Imagon brochures at

<a href="http://www.cameraeccentric.com/html/info.html">http://www.cameraeccentric.com/html/info.html</a>.

The newer one (with what appears to be a date code for 1964) has

a coverage table that lists the coverage of the 360 mm Imagon

in Compound V as 13 x 18 cm (i.e., 5x7, not 8x10)-- see <a href="http://www.cameraeccentric.com/html/info/rimagoncat/rimagone.html">http://www.cameraeccentric.com/html/info/rimagoncat/rimagone.html</a>.

But as people write on the internet, YMMV -- maybe you will like the effect of the softness on the corners. I think I have seen postings of people using the 360 Imagon on 8x10.</p>

 

<p>The brochure makes it clear that Rodenstock once sold the 360 Imagon in the Compound V shutter, so your lens may not be a re-mount.

As long as the throat of the shutter doesn't restrict the optical path, I don't see any reason why the shutter should reduce the coverage. The disk is all the way at the front, and the optical group all the way at the back. There is no shutter element in front of the disk, or behind the single optical group, to obstruct light rays.

If the shutter opening between the disk and the glass lens is as wide as the opening of the barrel version, the coverage of the shutter version should be the same as the barrel version -- it is that simple. You have both versions -- do they look to have the same dimensions?</p>

 

 

<p> The main issue is whether the single optical element delivers a sharp image over a large enough angular field to cover 8x10. From the brochure mentioned above, Rodenstock didn't think so. You will probably have to form you own opinion. Perhaps you can rent a 8x10 camera for a weekend or a few days? Or arrange to borrow one? Even if you have to pay to have a lensboard machined to hold one of your lenses, that is a lot cheaper than buying an 8x10 camera and then changing your mind. It might be cheaper to experiment with a 10 sheet box of transparency film and a few filmholders, unless you already have the Polaroid equipment.</p>

 

<p>If you find the coverage just shy of 8x10, you could arrange you compositions to avoid details in the corners, or crop the polaroids slightly.</p>

 

<p>The brochures on Seth's page (link above) give some guidelines on using the lenses. The manufacturer intended the disks to be used to control the exposure and the softness effect, not the aperture of the shutter. So you don't need the markings made by the previous owner. Of course, you can use the lens in any way that you wish. I made some remarks about the theory and usage of these lenses at <i>Fujinon 180 SF vs Rodenstock 200mm Imagon</i> / <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00BSYF">http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00BSYF</a>.</p>

 

 

 

<p>P.S. I don't think a projecting an image onto a piece of paper will tell you the useful coverage of a lens -- this more a determination of the circle of illumination. You won't be able to judge the resolution as well as you would a piece of film.

The image might look OK projected on the paper, but lack sufficient

resolution to look excellent for a contact print. (And the problem is even more severe for someone who wants to make images onto film that will be enlarged.)</p>