View Full Version : 1920s Kodak to Dichroic Filter Design

Mustafa Umut Sarac
06-30-2010, 12:58 PM
I am interested in scientific especially laser optics , electronics , mechanism catalogs and I found that it is possible to order your special sensiometry filters from military , remote sensing filter makers.

I watched a excellent movie someone posted from kodak , it was 1920s kodachrome movie film.

It is said it was two color film and it makes two color special order dichroic filters.

Can anyone post these each of sensiometric curves of this two color film ?

I think this is the biggest step to get these excellent colors back to photography.

Thank you ,

Mustafa Umut Sarac


Mustafa Umut Sarac
06-30-2010, 01:24 PM
May be we can make a stereo MURA or pinhole camera - escaping from special color rendition of lens - and attach these two filters and take great colors with 3D.

I dont know the chemistry but may be we can find the chemicals for these original colors , prepare gels and injection or spin mold and mass produce these colors as filters.

May be filters might optimized for tri x film also but I think filter guys can do it. They landed to moon at 60s .

Mustafa Umut Sarac


06-30-2010, 02:16 PM
For two colour separation work the visible spectrum is not divided in three but two.

Typically cyan and orange.

06-30-2010, 02:22 PM
Two color processes were common in the early days of color photography. Many used prisms/beam-splitters to make two different-colored images on the same strip of film. The same prism was used upon projection. I don't think it would be too difficult to find this information and/or the filters themselves.

What is stereo MURA? Could you please elaborate on your pinhole idea?

That was a very cool film reel, I guess I didn't realize it was two-color!

update: here are some starting points.... (some patent links, which might have spectral characteristics)

Mustafa Umut Sarac
06-30-2010, 02:40 PM
MURA is a technology which multiple pinholes placed in front of film in a fractal order. Result is not a picture but a blur. Computer decipher it. It is a basic lens but very much light gathering capacity.
We have two filters and will have two lenses and stereo image. One is right , one is left.
MURA or pinhole do not distort the color and this is essential for this purpose.
I am not after finding 80 years old hardware but finding a simple technology for new hardwares.
So the sensiometric information is a must.
AgX , what is cyan , what is orange ? There are millions of possibilities. And I am after reinventing the original if it is possible.

Mustafa Umut Sarac
06-30-2010, 02:47 PM
And some say red orange , green cyan. I think someone have information on finding the sensiometric information.

06-30-2010, 02:47 PM
You could pick two spectra points and just experiment. Or, you could find the 80 year old hardware and study it. Either way, check the patents for the old processes.

Do you have any MURA links? It sounds fascinating and I couldn't find any (yet).

Update, found it.... http://www.paulcarlisle.net/old/codedaperture.html

Mustafa Umut Sarac
06-30-2010, 03:00 PM
Thank you Holmburgers , I just started to dig the links. Thank you.

Mustafa Umut Sarac
06-30-2010, 03:03 PM
I cant study old hardware , Its a huge difficult option. I will look to the patents. But if someone have detail in his her hand , please post .

Photo Engineer
06-30-2010, 03:05 PM
IIRC, some of this early work was done by Sir Robert Hunt of Kodak Harrow. One of the first color enlargers made by EK was designed by Bob and was placed in the George Eastman House this year. I believe that it too used dichroic filters. The early Kodachrome predates his work by quite a few years though.


Mustafa Umut Sarac
06-30-2010, 03:59 PM
Ron , It makes everything simple and cheap. Two dichroic filters cost 2 inches diameter 50 dollar , 1 inch diameter 35 dollars. Is it that simple to get the look of old films ? Is there a modern photographer of this technology ? It is huge different from todays japanese cameras and modern films. I am thankful to find my rollei 35 s with sonnar and old summitar experience showed me these lenses are very capable to produce rich colors but at dim light. This is two color technicolor. Negative of this picture is green heavy at skin colors .

http://upload.wikimedia.org/wikipedia/commons/0/08/Anna_May_Wong_holds_child_in_The_Toll_of_the_Sea.j pg

Mustafa Umut Sarac
06-30-2010, 05:55 PM
The composite is an approximation of the original colors. Technicolor had a lot of latitude in their system. They could alter the tone and density of the dyes used to make the prints, along with adjusting the contrast and brightness of each record. We assume we've come fairly close to showing the original image.

Mustafa Umut Sarac
06-30-2010, 06:04 PM
Seen top left is the red record, printed and tinted with a green-blue dye. Top right is the green record, printed and tinted with a red-orange dye. At bottom is the cemented composite print. It is understandable why Dr. Kalmus would later decide that the company would print framelines on the base film when they went to three color printing.


Mustafa Umut Sarac
06-30-2010, 06:06 PM

Mustafa Umut Sarac
06-30-2010, 06:08 PM
Is it possible to find the original sensiometry of these emerald green and burnt orange colors. I think I have to learn this.

Marco B
07-01-2010, 03:09 AM
Mustafa, I actually see two questions intermingled in your thread:

- What were the cut-off points of the filters used to create the two images on the two parallel running films?

- What was the exact dye composition of the dyes used in this two color process?

I am slightly afraid there will not be a hard answer to these, as you yourself already wrote:

The composite is an approximation of the original colors. Technicolor had a lot of latitude in their system. They could alter the tone and density of the dyes used to make the prints, along with adjusting the contrast and brightness of each record. We assume we've come fairly close to showing the original image.

I think both the used filters, and dyes, will have been experimented with quite a lot, and maybe even changed upon need.

Of course, some record of used equipment and dyes might help to get in the ballpark for replicating the process and colors, but in the end, I think you will just have to give it a try and see what works best. Maybe you could consider contacting George Eastman House, as the original video I posted here on APUG and that spurred your interest in all this, came from there. They may have some records on this.

Mustafa Umut Sarac
07-01-2010, 08:03 AM
Marco , I spent the last night diving in the internet and I found a russian site which posted 1940 Dye Technologies of Kodak book. I saw there many chemicals for example for green have extremelly different sensitometry. And I found ph degrees change the curve also. But When I look to the patents , for two color process of 1922 to 1927 , used salt of sulfonic acids. This information narrows the search.

I think I need the first book of Kodak written at 1920 , not 1940. I believe this will make the search field narrower. I wrote to Eastman House and waiting an answer also. Its too difficult for me to read book from screen and I think I will order a print and look for the clues.

This video was a eye opener for me and Thank you very much.

It is quite interesting how much research done on this field and the wide palette of chemicals even 90 years ago.

So I need answers to my specific questions , try and hit is impossible , its like finding the technology of Egypt Pyramids building technology with experiment.

Marco B
07-01-2010, 09:30 AM

You may also find this link useful. It is a research site of the George Eastman House, with lots of documentation, including historic stuff:


Especially this "Materials" page might be of some help:


And maybe the there linked summaries of the historic British Journal of Photography as compiled in a PDF:


Other possible useful links:
British photographic history - Information and discussion on all aspects of British photographic history (http://britishphotohistory.ning.com/)
American Institute for Conservation of Historic and Artistic Works (http://www.conservation-us.org/)
Canadian Conservation Institute (http://www.cci-icc.gc.ca/index-eng.aspx)


Mustafa Umut Sarac
07-01-2010, 09:45 AM
Thank you Marco , I have to look at archive org for 1920 Dye Technologies book from Kodak also.
I researched patents until 1930 and it says after applying dyes to the film , rinse with water. Is it makes water soluble sulfonates ?

Mustafa Umut Sarac
07-27-2010, 06:32 PM
I found this at cinematographer website. It is about filters and their use at technicolor process.

>The 1956 production of MOBY DICK was shot in Technicolor and so >muted that when the film started you wondered if it was color or just a >tinted stock.

Actually it was shot on Eastmancolor 5248 (25 ASA tungsten) and printed using Technicolor's dye transfer process. What gave the prints that unique look (and the studio only allowed half the prints to be made this way) was that the three B&W positive separations made from the monopack Eastmancolor negative used "broad" or "wide cut" filters instead of the correct "narrow" or "clean cut" filters.

This means that the separate red, green, and blue records on the B&W positive "matrices" still contained information from the other two colors. When recombined using the dye transfer method onto the blank receiver, a very desaturated and somewhat low-contrast image resulted.

Technicolor Labs had developed this technique to make prints for film-chain transfers to TV. Ozzie Morris saw one of these prints being screened at Technicolor and decided to use that approach for "Moby Dick". The only problem was the low-contrast look, which they didn't want. Luckily, Technicolor still had set-up in their dye transfer printing line a fourth pass for adding a silver "key" image, used in the 1930's to improve the blacks in the print but discontinued when the process was improved and didn't need the silver key image, allowing the stronger color saturation of late 1930's dye transfer prints.

John Huston and Ozzie Morris did shoot "Moulin Rouge" using the 3-strip Technicolor camera process but it was discontinued by the time of "Moby Dick."

John Huston wanted to use the same printing technique on "Reflections In a Golden Eye" as he did on "Moby Dick" but by then, Technicolor had removed the fourth silver key printer from the dye transfer line-up (or perhaps Technicolor Italia, who did the printing, never had the fourth printer installed). Instead, a more elaborate method of printing a B&W dupe image over the color image was used. I don't recall the exact method but I do have the old "American Cinematographer" article on it somewhere in a box.

David Mullen
Cinematographer / L.A.