8mm Forum: Kowa Anamorphics

This is topic Kowa Anamorphics in forum 16mm Forum at 8mm Forum.

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Posted by Martin Jones (Member # 1163) on August 27, 2009, 08:46 AM:

Basically addressed to John Whittle, but input welcome.... I've been trying to find a reference to the Kowa 16-A that I have, without success. Do you know anything about it?
It focuses from 5ft to inf. has a 39 (?) mm rear thread, a 30 mm rear element and a 50 mm front element; 2:1 ratio. Mine has an adapter for B&H lenses but I don't know if that was original with it. Any help would be appreciated.
Martin

Posted by John Whittle (Member # 22) on August 27, 2009, 10:33 AM:

I'll try and remember all the various Kowa lenses.

There was the Vidoscope which was a 2x lens with the same rear barrel as the Bolex Moller (which was 1.5x).

Then the various letters which were all different than the Sankor for whatever reason:

16A that you have which I think was the same as the 16S or small barrel. These were the Japanese standard and fit the Eiki lens holder and the standard Elmo holder. The same diameter as the Sankor 16C (which was the same as the Sankor 16F which didn't have external threads on the rear barrel). Barrel is 43mm. I think the thread is 39.5mm.

16H which was the same lens as the 8Z which was the large barrel the same as the Sankor 16D. There was a special Bell & Howell lens made by Kowa which came with a screw in size rear barrel for the B&H projector lens. Barrel is 52mm.

Then there was a Kowa 1.5x lens which was used by still photographers and a Kowa 1.75X which was used by Inflite for scope pictures which were printed for it because it maintained the 35mm aspect ratio of 2.35/1 instead of the 16mm 2.66/1.

It was common for all these lenses to have available a complete set of rings and holders for various projectors. In fact back in the 1960-70s there was a full set of brackets for all the popular 16mm projectors and slight modifications were made for some lenses of various barrel diameters. In fact Panavision sold the same holder will a different bore for their Panatar 16 variable anamorphic lens and then a ring so the same brackets would hold the Superama 16 2x lens.

The same brackets and rings worked with the Sankor lenses, but there was a big difference in lens formula between the two. The Kowa 16H is much shorter than the Sankor D while both share the same rear diameter barrel and the same front element size. For my money, I've found the Kowa lens to have better contrast and in short that makes it look sharper than the Sankor.

The Sankor lenses abound in OEM circles and you'll find them engraved as Victor, Graflex, Telex, Eiki, Elmoscope, etc. Eiki and Elmo sold both Kowa and Sankor adapters. Most of the Eiki projector lenses were Kowa.

Posted by Martin Jones (Member # 1163) on August 27, 2009, 10:57 AM:

So, basically, the different letters A, Z, D etc. were physical size variants of the same Kowa lens (Except for the shorter ones which would have had to have different power elements to achieve the more compact format). I also have a Proskar 16, which looks very similar, an Iscomorphot that was made specifically for projection only and one I made myself back in the 50's before they were commercially available on the amateur market. We used that one on a GSAP aircraft gun camera to film a commercial for our college Annual Dance!
Thanks for your help.
Martin

Posted by John Whittle (Member # 22) on August 27, 2009, 01:51 PM:

Basically yes. There are formula differences between the 43mm lens and the 52mm lens (refering to the back barrel diameter).

Then of course there are differences when the compression ratio is different.

Basically any Anamorphic can be used for both photography and projection. The problem that you run across is focusing some of these lenses for normal photography (i.e. many 35mm adapters don't focus closer than 50 feet) but this can be corrected with diopters. Thru the lens focusing is necessary and you should focus your prime lens first and then the anamorphic should be adjusted. Technically the anamorphic is adjusted for astimatism correction and not focus--it only really brings in the image into "focus" in the horizontal direction.

Also most anamorphics can be reverse mounted (this was common in drive-in theatres with extreme focus requirements) but this often requires a glass to glass mounting of the adapter.

I am fond of the Old Delft lenses which are a also sold as Vistascope lenses. These were made in both 1.5x and 2x ratios and hold focus without adjustment. They are made up of two right angle prisms and the roof of each prism is cut in a cylindrical mode to provide the compression.

Once again the same lens can be used for photography and projection. The 1.5x lens was made in a "key chain size" for 8mm use. There was also a "super size" 1.5x used for slide 35mm cameras.

There are lots of variations out there and some unusual adapters turn up from time to time.

John

Posted by Kevin Wardle (Member # 1680) on August 27, 2009, 02:00 PM:

I have a Sankor 16C Scope lens on E Bay. Very good condition with original leather carry case!

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=300340985086&ssPageName=STRK:MESELX:IT

Forum members can have it £5 cheaper than listed! [Big Grin]

Thanx, Kevin

Posted by Martin Jones (Member # 1163) on August 27, 2009, 02:08 PM:

I also have one of the rarely seen "Magnarama" 1.75x Anamorphics. Very nice lens, but the "fore and aft" "Focus" adjustment is easily disturbed in use.
As you say, it's not really a focus adjustment at all; strictly speaking the lens combination is AFOCAL (a Galilean Telescope in the horizontal plane only). If anything, the lens movement relative to each other upsets this special relationship so the adjustment is a compromise between "focus" and "astigmatism".
If I recall correctly, there was also an amateur anamorphic called "Delrama" which employed two 60 degree prisms that could be rotated relative to each other to achieve various ratios, but this tended to suffer from colour dispersion. I experimented with the idea myself, but the prisms I used were very poor in that respect. A professional version for 35mm projection was made by Taylor Hobson which also was adjustable to give different ratios.
There is a Panavision Superama 16mm on UK ebay at the moment. I'm not giving a link because John has warned against the quality of this lens in the past.
Marrtin

Posted by John Whittle (Member # 22) on August 27, 2009, 04:03 PM:

The Delrama lens was made by Old Delft and the same as the Vistascope lens--just a different name. Old Delft also made a huge version for Technirama which was a foot across on the front element and weight 50 pounds or more.

The Old Delft was different than the prism method used by Panavision and Hilux and others. Those used the edge of the prism to spread on side and the second prism to correct spread the other side. By rotating the two prisms the amount of compression/expansion could be changed from 0 to 3x. These were also sold as Superscope lenses (and in fact it was the sale of those lenses around the world that introduced Sony Tape Recorders to the US in order to get their money out of Japan, the company imported the Tape Recorder rebadged as Superscope).

I remember reading of a method used in the UK that was actually off center of the projector and the image was projected in mirrors that were like the outside and inside of cans to expand the image. Lots of techniques in the early years when the original B&L lenses and licenses were horrendiously expensive.

John

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