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Linas Kudzma
21-Jan-2005, 13:32
Hello ULF friends,

Im just up from the darkroom after developing a 8x20 negative. My Kowa 240mm f9 almost covers 8x20, missing the corners by merely inch with nice resolution until just the very edge of the circle. This is better than my 10x12 Protar V, which misses the corners of 8x20 by an inch. The Kowas coverage is almost identical to my Wollensak Velostigmat 11x14 WA Ser. III f9.5 (focal approx 240mm). The negative clearly shows that the Kowa is more contrasty than the uncoated Wollensak. I know of no other modern coated lens under 270mm with such coverage that can be had for less than several thousand dollars.

I also just discovered that my Kowa 240 cells screw directly into an old Copal 3 of mine, but NOT into a modern 3. Did older Copal 3s have the same threads as the new Copal 3S (which are said to accept Kowa cells directly)? My old Copal 3 clearly says Copal-No. 3 with no S to be seen. Curious.

The above coverage test was using the Kowa 240 in barrel. I need to test the lens again in the old Copal 3, which spaces the cells 1mm further apart than in the original barrel.

Linas

Michael Mutmansky
21-Jan-2005, 13:43
Linas,

I believe, but someone can correct me on this if I'm wrong, that the Fujinon lenses in Copal #3 shutters are actually in #3S shutters. This means that older shutters you have may not actually be a #3, but a #3S, and just not have the label. I say this because my Fujinon 600C is in a 3S and is simply says "3" on the shutter.

As for the 240mm Kowa, if you are that close at infinity, I bet if you use a reasonable hyperfocal distance with the lens, you will be able to get it to cover. Since you have to use the lens stopped down to help address field curvature issues anyway, you can sefely move the lens out a bit from infinity.

---Michael

Linas Kudzma
21-Jan-2005, 15:31
Michael,

Thanks for the info. I neglected to mention that the Kowa 240 coverage test was with the lens focused approximately 20 feet away and at f90. Hyperfocal using a typical 8x10 circle of confusion would be about 8.5 feet at f90. So you are right, I might just squeeze out some more coverage this way.

My old Copal 3 is the home of a 12 inch Dagor and is apparently, as you speculate, really a 3S. Very fortuitous! I will be swapping the Dagor for the Kowa cells when needed. This allows the convenience of a shutter without the need to buy a Copal 3S, saving me a fair amount of coins.

Linas

luca_3797
21-Jan-2005, 18:14
Hi,
I'm interested on the discussion of the Copal # 3 .
There are some different old Copal # 3 model.
I have one that is all black and one it is white (witha old Fujinon W 300.
I 'm wondering if the front cell of a new fujinon 600 C can be fited on the new one....
Thanks
Luca

sanking
22-Jan-2005, 11:54
Linas,

If I were you I would try to obtain a 270 mm Kowa or Computar for your 8X20. The 240mm, though it might just barely cover, leaves you without the option of using any movements at all on this format. With the 270mm you would have up to about two inches or so of movemnts.

The 270mm Kowa/Computar, like the 240mm Kowa/Computar and the 300mm Computar, will screw directly into a Copal 3S shutter.

But for 7X17 the 240mm Kowa/Computar is great.

Linas Kudzma
22-Jan-2005, 12:24
Sandy,

Thanks for the suggestion. I will keep an eye out for a Kowa 270 at a reasonable price. Especially since you say it will fit my shutter.

Im sure Ill find my 240 useful also. Lately Ive been shooting with extended panoramas in mind, somewhat like work by Art Sinsabaugh. A 5x20 contact print can exclude the corners of the negative and its an interesting format that Im starting to like very much. This is the reason for my mini collection of ultra-wides for 8x20. Ill finally settle on one lens (likely the Kowa 240) and sell the others.

Linas

Jim Galli
22-Jan-2005, 20:06
Here's the deal with the old Copal 3 shutters. When Schneider switched to Copal 3 shutters about 1970 or so Copal made them to the exact size and spacing as the old Compound 3 they were replacing. So you'll find early Copal 3 shutters with 56mm thread but the throat spacing is quite a bit different than the modern ones. You should measure your 240 with a caliper front to back in the barrel and then compare when it's in the early Copal. I think you may find the cell spacing is about 5mm+ more in the shutter than the barrel. That could compromise performance more than you can tolerate. The early shutters are great if you have a 420 Repro Claron or a 210 6.8 Angulon in a balky Compound and want to modernize a bit. They're most often found with 1970-ish 210 f4.5 Xenar and 300 / 500 Convertible Symmar.

luca_3797
24-Jan-2005, 02:33
Thanks Jim,
so what I have is the older early version Copal 3 shutters with 55 ~56 mm thread. It's white one and not black.(only the ring is painted black)

Linas Kudzma
24-Jan-2005, 05:45
Thanks for the info Jim. I carefully remeasured the total length of my Kowa 240 in barrel and in the old copal 3 (3S). Interestingly, the cells are 1.5mm closer in the shutter. Note this is the opposite of what I said in my first post. Im not sure how I made that mistake, but the below is correct:

Total length of lens in original Graphic-Kowa barrel 45 mm

Total length of lens in old Copal 3(3S) 43.5 mm