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Geoffrey_1456
28-Mar-2001, 17:02
Hi All,

I just purchased a Rodenstock Imagon 250/5.8 soft focus lens. While playing with it, I have not been able to get to a reasonable "sharpness" I would like to hav e. Could someone kindly offer me some tips on how to use a soft focus lens? Ma ny thanks!

Bob Salomon
28-Mar-2001, 17:26
Best to call us at 800 735 4373

But here are some tips:

1: use a 5:1 lighting ratio. 2: don't use umbrelaas 3: focus at the taking condition with the disk you want to use in place and set for the effect you want. there is a focus shift when you change disks. 4: To see what a properly focused image looks like place a halogen flashlight in the scene and focus on the lit bulb. When you see that the bulb forms a cross you are in focus. Then see what the image area that is in focus looks like.

5: You have at most settings a choice of 2 degrees of softness with the Imagon.

With no disk in place you have an exposure opening of 5.8 and maximum softness. With the disk with the largest opening in place with all holes open you are still at 5.8 but are sharper.

With that disk in the fully closed position or with the middle disk with all hol es open you are at 7.7. The first disk with all holes closed will be softer then the second disk with all holes open.

The second disk fully closed and the third disk fully open are the same opening but the third disk full open is sharper then the second disk fully closed.

With the third disk fully closed the Imagon becomes a sharp lens.

david clark
28-Mar-2001, 21:49
Hi Geoffrey, from my own experience, soft focus lenses are hard to catch onto. I don't have the Imagon. I have one that is the adustable variety and one that isn't. Mine are probably old portrait lenses that I use for landscape. I take it you are enlarging 4*5 and that is another variable in the mix. For me the tricky part is knowing what you f-stop/speed is and what that looks like on the ground glass compared to the finished print. If your final print is not sharp enough, maybe you can go up one f-stop at a time until you get the printed image you want. It is just tricky to use these lenses. I understand the best of the old soft focus pictorial photos are contact prints. Good Luck, David

David A. Goldfarb
29-Mar-2001, 06:02
There is a very good post with some historical perspective on this topic in this thread:

http://hv.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=003WxF

Geoffrey_1456
29-Mar-2001, 10:58
Thanks, guys!

My primary interest is landscape/cityscape, so I can not re-create an ideal 5:1 light ratio. With the iris wide open, no matter which disk I use, I just can't focus well. It must be an aging issue (I'm now really wishing for an AUTOFOCUS Large Format camera!). However, if I close down the iris to about F11, focusing is OK. Then, open the iris and shoot. The Polaroids looked fine. Does this procedure cause any focus shift in theory? Bob, could you please explain to me how focus shift work? Thanks,

Bob Salomon
29-Mar-2001, 12:24
Yes, call me at 800 735 4373 and I can answer all of your questions at one time.

Paul Schilliger
29-Mar-2001, 12:35
I am glad the question was asked and thank you, Bob for your reply. The bright s potlight placed in the field of focus is a good idea! I seize this opportunity to ask you if the stars (spoke wh eels) produced on film by small light sources such as candels is something one can avoid by changing disks or op enings, or is it part of the Imagon design, like the white rings are part of the mirror lenses design?

Bob Salomon
29-Mar-2001, 13:50
All disks produce stars

Geoffrey_1456
29-Mar-2001, 14:43
Thanks, Bob!

cosmicexplosion
26-Jul-2012, 06:44
Yes, call me at 800 735 4373 and I can answer all of your questions at one time.


but then we all would be in the dark!

eddie
2-Aug-2012, 05:25
but then we all would be in the dark!

This could have been the oldest revival of a thread i have seen.....all ghe way from 2001.

Why not call bob. He is still active. (use skype!)

cosmicexplosion
2-Aug-2012, 06:56
Oh whoops, blush...i guess someone has to be the biggest idiot!

I must have been searching away
And forgot what time zone I was in
Lucky I'm not an absent minded time traveller
Then again....

Tin Can
7-Oct-2023, 01:38
More Imagon wisdom from past

Thanks Bob

Vaidotas
1-Nov-2023, 06:43
243487

Kind of approach, found on german LF forum.

xkaes
1-Nov-2023, 07:29
Here is information on how to focus the Fujinon soft-focus lenses -- in the Fujinon lens owner's manual. I can think of no reason it would be different for other SF lenses:

http://www.subclub.org/fujinon/lensmanual.pdf

Louis Pacilla
1-Nov-2023, 08:04
Here is information on how to focus the Fujinon soft-focus lenses -- in the Fujinon lens owner's manual. I can think of no reason it would be different for other SF lenses:

http://www.subclub.org/fujinon/lensmanual.pdf

In my experience owning quit a few different SF/ Diffused focus lenses & in my experience they do not ALL work act or alike & no one manufacturers instructions will cover use of all types/makes. The best way to know the SF/diffused optic is through use and "getting to know" the lens.

No offense meant xkeas just my experience.

Daniel Unkefer
1-Nov-2023, 09:29
I have Olde Imagon literature (a lot of it, some in German) which states the Imagon is "focus extending". The idea of a "belt of focus" rather than a "plane of focus" as described in the above attachment, seems about right to me. It is an acquired skill to get used to focus the Imagons. I do love mine and I have am happy to have a complete set from 120mm to 420mm. Somebody should 3D print Imagon discs for $$$, the chances of finding correct original discs (especially the large ones) is miniscule. I know I would buy some :)

jnantz
1-Nov-2023, 09:38
the WOllensak Veritar instruction manual it says to stop the lens down a little and then open it up afterwards to the desired level of softness. works well with imagon, vitax, verito, vesta, fast tessars and homemade Wollaston .. might work with others too .. can't be sure ..

Tin Can
1-Nov-2023, 10:23
Some times what you see is not what you get

jp
1-Nov-2023, 10:58
Focusing technique will vary slightly between lenses. What aperture to use can not be adequately judged on the groundglass. You really have to try some different apertures on different subjects to fine tune what you like for sharp versus soft, as the aperture choice affects softness as well as focus. After 50-100 sheets of film, you'll find an aperture choice you like best for that lens and learn to keep the lens at that aperture.

Tin Can
1-Nov-2023, 12:24
Some times what you see is not what you get

jnantz
1-Nov-2023, 12:35
Focusing technique will vary slightly between lenses. What aperture to use can not be adequately judged on the groundglass. You really have to try some different apertures on different subjects to fine tune what you like for sharp versus soft, as the aperture choice affects softness as well as focus. After 50-100 sheets of film, you'll find an aperture choice you like best for that lens and learn to keep the lens at that aperture.

yup. like everything experience is the key because WYSIWYG might be WYSMNBWYG

cowanw
1-Nov-2023, 13:45
One thing that becomes apparent with these lenses is that wysiwyg on the GG is not really true.
I have found it very heplful to use a sharp specular light source such as a old maglight with the top screwed off, with the older style of bulb, not LED.
With various soft focus lenses, I find a real difference in the nature of the depth of field in front of and behind the subject (the light filament)
The Universal Heliar, Kodak Portrait, Verito, Imagon and Veritar all maintain the central core of the filament when the bellows are focused closer. Focusing towards Infinity the filament changes to a diffuse circle with a dark core. This suggests that the most appealing use of the increased depth of field is found if these lenses are focused on the nose to use the depth of field to extend back to the catch light of the eyes.
The Kodak portrait lens manual on Camera eccentric agrees with this, describing racking the bellows out to focus "the tip of the nose to bring the face into the depth of field". It is a bit confusing about the depth of field being behind the lens focus but it is clear the bellows is racked out to the nose so the face is in the depth of field. "The lack of depth of field is in front of the focused plane." (not behind)
The Kodak manual for the Portrait lens says to use the normal focusing point and then apply a correction for the lack of depth of field in front of the lens, focusing at the working aperture. The plane of focus is moved forward say to the tip of the nose to include the face in the depth of field. Rack out 1/8th inch for a 2 inch head; 3/8th in for a 3 inch head and ½ in for a 5 inch head.
Or just focus on the nose.
The Graf Variable, the RVP and the Komuranon SF maintain the best use of extended depth of field when the bellows are focused towards infinity or shortening the bellows. The manual of the Graf suggests focusing on the eyes and the instructions warns against too much bellows extension.
The Cooke soft and the Velostigmat soft favour neither front or rear depth of field.
Whether you focus forward or behind your chosen focal plane depends on the nature of the soft focus lens you are using.

xkaes
1-Nov-2023, 14:02
the WOllensak Veritar instruction manual it says to stop the lens down a little and then open it up afterwards to the desired level of softness. works well with imagon, vitax, verito, vesta, fast tessars and homemade Wollaston .. might work with others too .. can't be sure ..

That's exactly what Fujinon says as well. If nothing else, it's a great place to start. Kind of like the manufacturer's recommended ISO.

xkaes
1-Nov-2023, 14:07
I have found it very heplful to use a sharp specular light source

That's also what Fujinon suggests.

Tin Can
2-Nov-2023, 06:46
Many dislike Fujinon SF as Harsh

So I never bought one

Cooke SF changed instructions way back, I have 2, I like both Knucklers

1 big Verito almost mounted

2 Wolliston modern, affordable

! huge SF KODAK the most difficult

I really like my 3 Imagon as they have better tricks

more are waiting for time

Daniel Unkefer
2-Nov-2023, 07:42
https://live.staticflickr.com/65535/53304814651_c12da98bc9_b.jpg (https://flic.kr/p/2pdn7ht)Imagon Tiefenbildner 1 (https://flic.kr/p/2pdn7ht) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

https://live.staticflickr.com/65535/53303972657_bec99501f7_b.jpg (https://flic.kr/p/2pdhMZk)Imagon Tiefenbildner 2 (https://flic.kr/p/2pdhMZk) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Notice how the "belt of focus" is slightly forward in terms of DOF.

https://live.staticflickr.com/65535/53305215994_180c2c54db_b.jpg (https://flic.kr/p/2pdpaAb)Imagon Tiefenbildner 3 (https://flic.kr/p/2pdpaAb) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

Notice the low values remain sharp.

jp
2-Nov-2023, 07:49
Here's what I've enjoyed with sufficient practice (wasted film and worthwhile images)
Gundlach Hyperion 9"
Verito 7.25"
Kodak 305 on 8x10
Wollaston Meniscus
Magnifying glass with spaghetti measure aperture

I've tried the Fujinon with 4x5 and didn't find it soft enough but depth of field didn't drop off a cliff like a tessar/planar. If you want a gentle smooth triplet like the meyer trioplan, this is a good shuttered option.

I still have to spend some quality time with a wider Verito and a Spencer port-land.

Daniel Unkefer
2-Dec-2023, 12:22
https://live.staticflickr.com/65535/53371277319_41e215a9ea_h.jpg (https://flic.kr/p/2pjeKjx)Rodenstock Imagon 1 (https://flic.kr/p/2pjeKjx) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

https://live.staticflickr.com/65535/53371150818_a71bbd805c_h.jpg (https://flic.kr/p/2pje6Hu)Rodenstock Imagon 2 (https://flic.kr/p/2pje6Hu) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

russyoung
24-Dec-2023, 06:36
Here in ENGLISH are Heinrich Kuhn's instructions for using his Imagon invention: https://www.cameraeccentric.com/static/img/pdfs/imagon_2.pdf

Russ

djdister
24-Dec-2023, 07:18
These instructions for the Verito from 1916 says to simply focus at whatever f stop is most pleasing for the effect...
244946

Mark Sawyer
24-Dec-2023, 14:06
Here in ENGLISH are Heinrich Kuhn's instructions for using his Imagon invention: https://www.cameraeccentric.com/static/img/pdfs/imagon_2.pdf

Russ

It should be noted that the technique for focusing the Imagon with h/stops is very different than for other soft focus lenses with conventional f/stops. With the Imagon, you focus on the sharp image with the h/stops closed, then open the h/stops to add the glow of spherical aberration. With conventional f/stops (including when using the Imagon with a conventional diaphragm), just set the aperture for the desired degree of softness and "focus to taste". With a panchromatic emulsion, what-you-see-is-what-you-get.

Bob Salomon
24-Dec-2023, 14:13
It should be noted that the technique for focusing the Imagon with h/stops is very different than for other soft focus lenses with conventional f/stops. With the Imagon, you focus on the sharp image with the h/stops closed, then open the h/stops to add the glow of spherical aberration. With conventional f/stops (including when using the Imagon with a conventional diaphragm), just set the aperture for the desired degree of softness and "focus to taste". With a panchromatic emulsion, what-you-see-is-what-you-get.
No, there is a focus shift when you change H stops on the Imagon. You must focus it at the desired H stop.

Mark Sawyer
24-Dec-2023, 14:32
No, there is a focus shift when you change H stops on the Imagon. You must focus it at the desired H stop.

Not according to Kuhn, and his method makes sense if you want a sharp image with a soft overlay. Focus for the sharp image for the central aperture, then add the soft effect from the peripheral h/stop apertures. The out-of-focus shift IS the soft effect. If you focus with the h/stops open, they may compromise the sharp image from the central aperture, which throws the dominant image.

In practice, we do what we want.

From Kuhn, in the link Russ posted:

Bob Salomon
24-Dec-2023, 14:57
Not according to Kuhn, and his method makes sense if you want a sharp image with a soft overlay. Focus for the sharp image for the central aperture, then add the soft effect from the peripheral h/stop apertures. The out-of-focus shift IS the soft effect. If you focus with the h/stops open, they may compromise the sharp image from the central aperture, which throws the dominant image.

In practice, we do what we want.

From Kuhn, in the link Russ posted:

Why not quote Rodenstock’s instructions? Then you would avoid the focus shift.

Mark Sawyer
24-Dec-2023, 15:39
Why not quote Rodenstock’s instructions? Then you would avoid the focus shift.

Having the soft image from focus shift overlaid on the sharp image is the whole point of the Imagon.

To quote from the Rodenstock's instructions online at: https://www.cameraeccentric.com/static/img/pdfs/imagon_1.pdf

xkaes
24-Dec-2023, 15:55
That's exactly what Fuji says as well -- focus stopped down on the most important feature. Then open up to get the softness you want. I posted that six weeks ago.

Around and around we go.

244949

russyoung
27-Dec-2023, 04:29
Having the soft image from focus shift overlaid on the sharp image is the whole point of the Imagon.

To quote from the Rodenstock's instructions online at: https://www.cameraeccentric.com/static/img/pdfs/imagon_1.pdf

Later instructions, written by Joseph Foldes for IMAGON also note to focus with the peripheral holes closed then open up: https://www.cameraeccentric.com/static/img/pdfs/imagon_1.pdf
russ