? Rodenstock Tiefenbildner Imagon 300mm and disks?

[eddie]

hi all,
i got this in a package purchase. i have never seen one before. it is a 300mm lens (rear element only) H 5,8. the disks are added to the front in a diffusion style soft filter set up.

there are 3 disks. H5.8-7.7. a 7.7-9.5. and 9.5-11.5. they all open and close the diffusion holes by turning the ring on the disks. it is in a compound shutter.

anyone got any extra info on this lens? what is the value?

i plan to shoot it this week.

thanks.

eddie

[Ole Tjugen]

http://www.cameraeccentric.com/html/...imagoncat.html

When in doubt, check with cameraeccentric.

[eddie]

thanks ole. i added camera eccentric to my bookmark.

eddie

[Ted Harris]

One problem, there is a typewritten article at cameraeccentric on using the Imagon that contains some incorrect info. If you search the archives on this Forum you will find a number of threads on the lens and how to focus it.

Eddie, the Imagon is a variable focus lens and the discs serve the same purpose as an iris on a regular lens/shutter combo. You shoot this lens with the shutter wide open and use the discs to vary the "H" stop.

I use the lens largely for portraits and product shots. Note that the 300mm lens is designed for 5x7 and will not give you the most desirable diffusion effects on 4x5 (you need the 250 for that). You must focus the lens at the taking aperture (that is the mistake in the typewritten document). The easiest way to do this is to put a point source light in the image and focus on that. When it is a sharply focused starburst you are in critical focus (thanks to Bob Salomon for this tip). After you focus remove the light source and shoot.

[Peter K]

Hi Eddi,

"H" stands for "Helligkeit" = brightness. With the largest sieve and all holes open you will need an exposure-time like at f/5.6 with a "normal" lens. With all holes closed it's like f/7.7. And so on with the other sieves. As smaller the sieve, as "sharper" the image. But when you want the softness of H 5.6 and the minimum speed of the shutter is too long, you can use the gray-filter (with very old Imagon's it was a yellow-filter) with filter-factor 4.

The Imagon uses spherical aberration. In this way each object is imaged sharply by the central part of the lens and superimposed by a soft image from the other zones. With the sieves you can choose the ratio between sharp and soft parts.

With the iris-diaphragm closed the Imagon is nearly as sharp as any other lens. You can also get nice images without any sieve.

Peter K

[Jim Galli]

Eddie, much offset in "value" is due to whether the lens is in a shutter. Some are in barrel, some in Compound shutter and finally some were in Copal 3. Each iteration increases value to a prospective purchaser.

[eddie]

thanks all.

it is in a compound shutter.

i will play wit it this week. i will use my 5x7 back and follow the above suggestions. cheers

eddie

[Thomas Greutmann]

I like the Imagon for its effects but it takes patience to really discover the potentials. I had several runs at it, some with disappointing results, some with fascinating pictures. So if you try the lens this week and don't get the results, try again in a couple of weeks or months.

The Imagon is often called a soft focus lens. I think this is the biggest misunderstanding which may lead you down the wrong path. While it has some capabilities for soft focus with the variable focus design, this is not the true strength of the Imagon. The true potential of this lens is that it can really make lights shine and radiate. This will show in subjects that have a high dynamic range with lots of contrast between light and shadow. For instance, leaves against sunlight. Try to use the lens for such subjects. If you use it for subjects with a low dynamic range the results may be disappointing.

There is a good German book about the Imagon, author is Alfons Scholz. The book is long out of print, you can get second hand copies occasionally but not cheap. The title of the book is "Lichtbilder mit dem Imagon". This is a pun but it really sums it up.
A Lichtbild is an old-fashioned word for a transparency slide but you can also read it as "image of the light". And that is, IMHO, what the Imagon does best: create images of the light. Go for the light, not for the soft/variable focus.

Greetings, Thomas