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View Full Version : How to use a Cooke Soft Focus Portrait Anastigmat (knuckler)



Tim Meisburger
16-Apr-2012, 04:00
I have a beat up old knuckler I picked up on a recent trip. Its missing the front ring that normally has the focal length and name, but I think it is a Series II. I could just experiment with it to see what it does, but I'm out of fixer:eek:

So, a few questions:

- I'm not sure which direction to turn the ring for soft focus. Turning one direction moves the front element closer to the rear, while the other direction moves it away from the rear element. I cannot see the softness in the ground glass. Should I be able to? (I have not used a loupe yet)

- Turned all the way in one direction the focal length is about 9", while the other way its 11 1/2". Is that normal, or is something put together wrong?

- is the softness dependent or independent of aperture? I mean, if I stop it down with the softness on maximum, will it be sharp, or still diffused?

Thanks for your help:)

jnantz
16-Apr-2012, 04:43
hi tim

i have never used a cooke knuckler ... maybe this link might be of some help
http://www.antiquecameras.net/softfocuslenses2.html

good luck!
john

cosmicexplosion
16-Apr-2012, 05:19
craig tuffin from this forum uses one...

Tim Meisburger
16-Apr-2012, 05:27
Thanks John. I looked at that earlier. It is primarily testimonials and lens information, rather than instructions.

Cheers, Tim

Emil Schildt
16-Apr-2012, 05:40
Hi Tim.

An image of your lens would help determing what type it is...

I have two. When I hold the lens, pointing away from me, the soft focus turn is anti clock wise - (left turn) - sharp is clock wise.

iirc, when I see my image on the matt screen, I can see the softness, bu tmore suttle than onother SF lenses.
And again iirc, I think it is correct that the FL changes turning the soft focus. So chose the SF first - then focus.

In my ecperience the amount of soft focus is bigger on the negative than you'd think.

Also the direction of the light is of importance - backlight makes glowing whites...

I have a couple of examples. See attach.

Have fun and try it soon. rather addictive!!

BTW: the amount of softness is biggest on full aperture.

eddie
16-Apr-2012, 06:04
Yeah. A picture and some measurements of the size of the actual lens. Flange. Etc etc will help to determine which u have.

We know it is probably a 9 Inch lens or thereabouts.

I have several different series to compare to and Have handled pretty much all of the "regular" offerings from Cooke. So I hope to be able to help u.

Generally it takes lots of practice to see softness on many of the "sf" lenses. As a general rule any lens that has a mechanical softness dial I do not consider "true" sf lenses. BUT anyway with the mechanically adjusted lenses it is very hard to see the softness. Without lots of practice. Also subject matter comes into play.

Eddie

Tim Meisburger
16-Apr-2012, 06:05
Thank you Emil. That's very helpful. I'll try to post a picture of the lens tomorrow, and buy some fixer so I can start using it! I like the backlight effect of these soft-focus lenses. If you had to choose between the Cooke, and a Universal Heliar, which would you prefer? Or are they so different I should keep both..

Cheers, Tim

Emil Schildt
16-Apr-2012, 06:16
Thank you Emil. That's very helpful. I'll try to post a picture of the lens tomorrow, and buy some fixer so I can start using it! I like the backlight effect of these soft-focus lenses. If you had to choose between the Cooke, and a Universal Heliar, which would you prefer? Or are they so different I should keep both..

Cheers, Tim

Arck....:o

would I keep my father or my mother?

I'd keep them both. The ones I have I will never sell.
I love them both, even though they are similar (as far as I know) in the soft focusing.

And then I'd go look for more exotic sf lenses .... plasticca ex.

Tim Meisburger
16-Apr-2012, 06:44
Emil, that's what I thought you would say!

Eddie, I went and got the lens and a loupe and was finally able to decipher what is written int he black band. It says:
Cooke Portrait Anastigmat No. 415841 10 ½ Inch 270mm Series II E f4.5, so now I know. Why don't you like the lenses with mechanical softening? What would be better?

Here is a cell phone picture.

72126

Tim Meisburger
16-Apr-2012, 07:13
Interesting. Now that I know what the lens is I googled it and came up with this LFP thread from 2010: http://www.largeformatphotography.info/forum/showthread.php?64918-Taylor-Hobson-Portrait-Anastigmat-4-5-10-5in. The lens is the same, and the serial number is just three off from mine! Condition is quite different, of course, as mine came from a country where it was probably in daily use until a few years ago.

jnantz
16-Apr-2012, 07:21
tim

the booklet had a detail of your knuckler so you could tell which way was soft and sharp ( you weren't sure ) ...

good luck !
john

Tim Meisburger
16-Apr-2012, 07:40
Thanks John. Yes, I have figured it out now. The site had a link to an early 1920s catalog that recommended taking a sharp portrait, then using the same lens at maximum diffusion to soften the portrait during enlargement! I might give that a try sometime.

jnantz
16-Apr-2012, 08:11
yeah, a lot of these lenses worked "double duty" as both an enlarging/and taking lens.
i use a meniscus lens from time to time to enlarge, it works pretty well ..

Mark Sawyer
16-Apr-2012, 11:49
I was sorting out my Cooke's a few years ago. Here are examples from my 16 inch Cooke Series II wide open at f/4,.5:

Full sharp:
http://i55.photobucket.com/albums/g139/Owen21k/Cooke16a.jpg

Full soft:
http://i55.photobucket.com/albums/g139/Owen21k/Cooke16b.jpg

Detail, full sharp:
http://i55.photobucket.com/albums/g139/Owen21k/eyesCooke16a.jpg

Detail, full soft:
http://i55.photobucket.com/albums/g139/Owen21k/eyesCooke16b.jpg

The Cooke f/4.5 Portrait Lenses don't go as soft as other dedicated soft lenses. They're more a "true" portrait lens meant to smooth out skin blemishes, rather than to add the heavy shimmering atmosheric effects of a pictorial soft focus lens. There's definitely some spherical aberration spreading the depth of firld, you can see it in the wicker chair detail. My Cooke f/3.5 Portrait Lens goes a little softer wide open.

Wonderful lenses. The Cooke's seem to give a little something extra in the tonal range...

Tim Meisburger
16-Apr-2012, 16:18
Thanks Mark. Its very interesting to see the increased depth of field in the shawl and wicker. It is not the theatrical effect I expected, but does have a wonderful look, and clearly improves even teenage skin. I have some lights in the mail and am looking forward to doing some tests with this lens when they arrive.

It was interesting to read that this lens was intended for 4x5! It would never fit on mine, and just fits on the 5x7 B&J I have. The glass is so heavy the front standard tilts...

jnantz
17-Apr-2012, 05:30
hi mark

with the tests you posted, do you remember if your focus point was her eyes? it seems that the sharp/soft dial also changed the focus point
and "front focuses" your subject ( and softens everything behind the new focus point ) ...
this lens must do magic between 5.6 and 8 and the dial turned ...

john



I was sorting out my Cooke's a few years ago. Here are examples from my 16 inch Cooke Series II wide open at f/4,.5:

Full sharp:
http://i55.photobucket.com/albums/g139/Owen21k/Cooke16a.jpg

Full soft:
http://i55.photobucket.com/albums/g139/Owen21k/Cooke16b.jpg

Detail, full sharp:
http://i55.photobucket.com/albums/g139/Owen21k/eyesCooke16a.jpg

Detail, full soft:
http://i55.photobucket.com/albums/g139/Owen21k/eyesCooke16b.jpg

The Cooke f/4.5 Portrait Lenses don't go as soft as other dedicated soft lenses. They're more a "true" portrait lens meant to smooth out skin blemishes, rather than to add the heavy shimmering atmosheric effects of a pictorial soft focus lens. There's definitely some spherical aberration spreading the depth of firld, you can see it in the wicker chair detail. My Cooke f/3.5 Portrait Lens goes a little softer wide open.

Wonderful lenses. The Cooke's seem to give a little something extra in the tonal range...

cdholden
17-Apr-2012, 06:33
John, you are correct. These lenses have a middle section that moves when the softness is adjusted. This changes the focal point because the optical formula changes as the positions of glass change with respect to each other.
In the past, I've owned a 16" Series II. I currently have a 10.5" IIa. Both are of similar construction. Both are "pre-knuckler". I think the black "knuckler" ring started being offered around 1924.

Mark Sawyer
17-Apr-2012, 10:27
John ~ Chris is quite right on all counts. I'm aware the focal length changes a touch with the moving elements in soft lenses, (the Vitax, Velostigmat, and Portrait Unar do the same thing, as I'm sure the Universal Heliar does). And yes, I always focus carefully on the eyes, usually with a little swing and tilt for other areas. For this one, I refocused after moving the mid element, and left the movements the same for comparison porposes. Something that surprised me was that the soft adjustment also softened the apparent light reflections on the skin, making it seem less shiny.

Tim Meisburger
17-Apr-2012, 15:36
Well, I'm still a bit confused, and wonder if my lens is assembled incorrectly, as when I shift the softness ring focal length at infinity changes from about 9" to 11 1/2"; i.e. not "a touch". Is that normal?

I was able to buy some hypo (and other chemicals) yesterday, but by the time I got set up the light was gone. I'll try to shoot some tests this afternoon when I return from work.

cyberjunkie
10-May-2012, 11:29
Interesting. Now that I know what the lens is I googled it and came up with this LFP thread from 2010: http://www.largeformatphotography.info/forum/showthread.php?64918-Taylor-Hobson-Portrait-Anastigmat-4-5-10-5in. The lens is the same, and the serial number is just three off from mine! Condition is quite different, of course, as mine came from a country where it was probably in daily use until a few years ago.

It's mine! :)
Did you buy yours in Thailand?
I spent many months in Thailand, during a good span of time (first time in 1978), and i like to think that i will spend the most part of the year there, as soon as i can afford it.
Are basic darkroom products and large format films available in Bangkok?

Back to the Cooke:
the IIE is the youngest brother, and i think it has more "travel" than the others, though i don't know if the amount of "soft" is increased or not.
The lenses with mechanical adjusting of "softness" are generally more subtle than those with diaphragm only... or those with no diaphragm at all, like the Plasticca (which is really super soft, and difficult to use, due to chromatic aberration).
Generally speaking, the lenses with mechanical adjusting are somewhat easier to use than an achromatic meniscus (like the Imagon), and much more than anachromatic lenses of various kind, like the Pulligny & Puyo and of course the Plasticca.
It's a matter of taste, and of course of time and personal efforts (a lens which has different chemical and visual focus isn't exactly easy to master), and of course there are individuals who are in love with their Universal Heliar or Cooke Portrait, and find a Plasticca totally unusable. BTW, i have seen a price list of the time, and with the same money you could buy about 10 Plasticcas, or ONE Universal Heliar of corresponding focal!

One personal opinion about the Cooke Portrait IIE: there are very few brass lenses that are so well made :D

have fun

CJ

Tim Meisburger
10-May-2012, 13:17
Thanks CJ. I bought it in Burma. You can still get chemicals in Thailand, but for film I normally mail order.

I have not used the Cooke much yet, as it only fits on my old B&J 5x7, but am looking forward to using it more in the next few weeks. Does the focal length of yours change when you adjust the softness? Mine changes from about nine to eleven inches, and if that is not normal then something is reversed!

Thailand is fine, but I work here, so its not like a holiday. For holiday, I'm off to Italy (Milano) with the family in July.

Cheers, Tim

coisasdavida
3-Jul-2012, 16:57
I just did a search as I was planning to place an ad for my Series II.
But after seeing the pics in the thread and reading it, I guess I'll my Cooke a second chance.