Graflex.org

[troublemaker]

I picked up a Cooke 7" f~4.5 Series II 5x7 anastigmat lens. Though the lens says 5x7 it came factory or professionally mounted on a black phenolic lens board that fits my Mini-Speed. However, I am wondering if this is also the same lens board for perhaps the same model period Graflex SLR cameras?
I am guessing it has a date of 1930's to mid 40's? The image quality is very good as far as sharpness, better than the 7-1/2" Kodak lens on my RB Series B. It is considerably better than the 7-1/2" Paragon currently mounted on my Speed 45 and which it will probably replace, thus lightening the camera from heavy Ilex shutter to compact lightweight barrel (will also have a board to mount it on Speed 23's and keep the Mini Board).
Because of the mounting I am assuming this was an option lens available at one time for Graflex cameras.
Any info would be appreciated, thanks


[ This Message was edited by: troublemaker on 2006-04-11 08:22 ]

[45PSS]

From the Lens Vade Mecum:
Series 11 Cooke Anastigmat f4.5 These were triplets, normally made in f4.5 and later in f3.5, and are portrait
lenses in the larger sizes. The foci were: 4.0, 5.0, 6.0, 7.0, 8.0, 10.5, 13, 14.5, 16in. The layout is as shown in
Tay003, Tay004. There may be slight changes in the designs here as the diagrams seen do seem to vary. It
was at first sold as a portrait lens, and the B.J.A. 1921, 557; 1925, p665 shows it as this:
10.5in focus 270mm for 8x5in format.
12.75in 325mm 9x7in
15in 380mm 10x8in
18in 460mm 12x10in
but it also developed into a first-choice standard lens for reflex and press cameras, a 1912 list showing it as a
triplet. It was suggested to use 13in for 10x8in, 6.5in for 5x4in. For portraits, it gave adjustable sharpness by
moving the rear glass and was sharpest with this 3 turns out. (B.J.A. 1900, p893), and this is engraved on the
rear cell at the example seen, No19,20x in brass. Shorter examples do not have the soft feature, eg at
No34,89x, for a 6.5in f4.5 lens in brass. It is a sharp lens then, and not very soft even screwed home.
Early in the Century, exchange rear cells were made. These were revised in 1910 (see B.J.A.) and replaced
the front glass of the lens instead of the back as in the other series. Series 11 (and Series 1V) was noted in
B.J.A. 1906 and there was an impressive set of test data by Mr S.D.Chalmers of the Northampton Institute
especially for field flatness.
It was also in 1910 that TTH began the supply of lenses in sunk mounts for reflex and hand cameras, and
these initially were 5, 5.5, 6, 8, 10.5in, in Series II, III, IV and V.

_________________
The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

[troublemaker]

well thanks very much.
The 7" I have here does appear to be a triplet and breaks down into three individual cells easily and does not appear to have any cemented cells making it the triplet you write of. It has the single element in front. The lens appears to be sharp with the rear cell all the way in or backed out a few turns. For the softy look I will just dress it up in some stockings or such...and keep all sorts of netting and other things around which work well also...
The lens makes focus up to four feet easily on the Speed 23 it is currently presiding on as I spun a lens board out on the lathe and this seems like it will make a superb portrait and long lens.
I assume that it is called an Anistigmat refers to its flat field rather than construction?
Anyway, thanks for all the suplemental info.

[45PSS]

That was a copy-paste from the Vague Mecum and the closest match to your inquiry. There are probably many minor varaitions of a base design.
Diagram TAY003 light travel-convex element with flat side rear-air space-double concave element-aperture-larger air space-convex rear element, flat side to inside of lens, may be slightly thicker than front element.
Diagram TAY004 light travel-convex element thicker than tay003 front element rear side slightly convex-air space-double concave element-aperture-large air space-convex facing rear element double thickness of tay003 rear element, not two elements cemented.
The Vade (vague) Mecum was based on lens sold in England (UK) and not the U.S.
Charles

_________________
The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

[troublemaker]

Thanks again Charles.
Just for curiosity I am always interested in the approx manufacturing dates of my gear. Do you know anywhere I might find this based on the Serial number? But like I wrote earlier, I am assuming late thirties to early forties due to the factory looking mount.
As a side note, though it looks too long at first glance, the Speed 23 closes easily with it installed. I do not know yet how accurate or close I will be able to get the RF to run with it. Experience suggests to me that I will be able to get it to work from about 6-8ft and maybe to infinity with the short arm of the smaller camera. Thus I eventually intend to install on a Speed 45 I have been working up. It will be nice to use this Cooke barrel in place of the Paragon in a heavy Ilex shutter.

[Dan Fromm]

[troublemaker]

Serial # 56069

[Dan Fromm]

[mav6977]

I have a catalog probably printed
somwhere between 1913 and 1915 from
the Z.T. Briggs Co. in Kansas City.
It shows several series of Cooke
lenses, including the Series II. About which it says "These ultra rapid anastigmats
are designed for subjects demanding
extreme speed. For pictures of fast
moving subjects at close range, and for difficult portraiture in dull lights, the lenses are unrivaled. The brilliance of the image is phenomenal". It show the 7 inch as a No. 21 and a half covering 5*7 with a screw flange diameter of 1 and three quarters of an inch that sold for $57.50 in iris diaphragm. It does not show the lens priced with a shutter of any kind. The coverage by the way is at full aperture. There are several types of Cooke lenses shown, such as Series IV F/5.6, Series IIIa F/6.5, Telar F/7 (Telephoto lenses), and Series IV Portrait Lenses. It also shows Cooke extension lenses to increase the focal lengths.

[troublemaker]

Interesting, I did not think the lens to be that old. I'll have to get it rigged up on a 4x5 and see how she does. If it covers wide open as suggested in the catalog, I did good as I got it for considerably less than the original selling price nearly a hundred years later.
So hey thanks for looking up the info; it is much appreciated.

[45PSS]

A $57.50 lens in 1915 would cost $1131.21 today. I think there are a few nice lens available for that price.

_________________
The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU.

[troublemaker]

Well good, I saved $1,094.21.

[troublemaker]

The rear group in this Cooke 7" doesn't change image sharpness much if at all when backed out as suggested above for other Cooke lenses. However, the forward element of the rear group looks almost as if it were meant to be moved the way the ring is knurled and easily turned. So I checked it out at half, one and two turns and the lens certainly does change personality when doing so. I shot film with it straight and it is really nice wide open. though certainly not as contrasty as the later coated Optar I was also using. I will run a testwith it with the rear manipulated for softnessand get back about it's usefulness, but it reacts in a unique way that should be fun, and can't be reproduced with mesh screen or soft suplimental add ons...

[troublemaker]

Two turns is too much. Where the image looks really nice and dreamy on the GG it created more of a double image flare rather than the foggy soft focus look. Stopping down even one stop from wide open at f~4.5 to 5.6 really negates the softness. Thus I will try it at one turn and a half turn this weekend.
Film developed from images this lens shot at Joshua Tree N.P. a week ago are very nice indeed. I used it mounted on one of my Speed 23's, shot it wide open in its normal configuration and got some highly detailed stuff. Definately a much sharper performer than the 8" Tele-Raptar, and much lighter... A nice option with lots of coverage. Now it goes for a spin on the 4x5...