what process came before C-22 if any?.

Recent Classifieds

Forum statistics

Threads
177,079
Messages
2,429,099
Members
94,125
Latest member
photomancottrell
Recent bookmarks
1

spoolman

Subscriber
Joined
Sep 7, 2007
Messages
599
Location
Toronto Onta
Shooter
Med. Format Pan
I was curious as to whether there was any process that preceded C-22 if any?. I googled "kodak colour processes for colour negs" and got a whole lot of vague material but no definitive answer.

Doug:smile:
 

septim

Member
Joined
Aug 15, 2013
Messages
59
Location
Blue Mountai
Shooter
Multi Format
All the information I can find seems to point to the color negative process prior to C-22 was just refereed to as Kodacolor Processing. Below is some of the information I found (for revision two of the Kodacolor processing):

The film had a black and white contrast “mask” layer between the yellow filter later and the green sensitive layer. The mask layer was a very slow speed, blue sensitive emulsion, too slow to be affected by any camera exposure. The film was processed to form a dye negative image in each of the three colour coupling layers. The film was then exposed to blue light through the base, printing the already developed cyan dye and magenta dye layers onto the mask layer. The exposure did not affect the blue sensitive top layer because the yellow filter , underneath the blue sensitive layer would “stop” any blue light. The mask layer was then processed in a soft working black and white developer to form a weak positive mask image of the shadow areas of the green sensitive layer and red sensitive layer. The exposure of this layer took place after the film had passed through the Bleach bath. The idea was, when the negative was printed onto Kodacolor paper, obviously through the base of he film,the mask would have held back some of the exposing light from the shadow areas of the negative, thus lowering the contrast. The processing sequence may have been something like the one used for the original Kodacolor film outlined above but with additional steps.
DeveloperForms a dye image in the three colour coupling layers
Stop-bath or Wash
BleachThe Bleach bath converts the exposed and developed metallic silver (camera exposure) to silver halide so it can be made soluble in the Fixer. The Bleach works only on the exposed, developed silver halide so the mask layer is unaffected
Re-ExposureThe film is re-exposed to blue light to print the two developed dye forming layers onto the mask layer. The film is exposed through the base
Black and White developmentThe Mask layer is developed in a soft working black and white developer
After black and white development and before fixing the film may have looked like this from the emulsion side downwards:
Yellow layer – Bleached exposed silver halide.
Yellow Filter - Still present.
Mask layer - Developed but not fixed.
Magenta layer – Bleached exposed silver halide.
Cyan layer – Bleached exposed silver halide
Fixer, performs the actions itemised:1. Colour Negative. Removes silver halide formed by Bleach in exposed dye layers to leave pure dye.
2. Colour Negative. Removes silver halide in unexposed dye layers.
3. Black and white positive mask. Removes silver halide in unexposed black and white layer to leave positive mask.
4. Removes yellow filter layer (or it is also possible that the yellow filter layer might have been removed in a separate bath inserted between steps 8 and 10 (see below), or it may have been removed in the black and white developer.
The Fixer leaves exposed metallic silver in the mask layer as this was not turned into removeable silver halide in the Bleach. All silver halide is removed from the negative dye forming layers to make a colour negative.

So I have also found reference to "Type B Processing" and "B-41" processing for EKTACOLOR (Yes, color not chrome) and "Vericolor Processing" for Type S and L Vericolor (1) film (Prior to Vericolor II/III which used standard C-41) the B and B41 processing certainly predates C22 but I believe that the Vericolor Processing was around at the same time as the C-22 processing.
 
Last edited by a moderator:

Mr Bill

Member
Joined
Aug 22, 2006
Messages
1,091
Shooter
Multi Format
Hi, there is a little bit of history in this thread: (there was a url link here which no longer exists)
 

MattKing

Moderator
Moderator
Joined
Apr 24, 2005
Messages
37,801
Location
Delta, BC, Canada
Shooter
Multi Format
As far as I am aware, the Vericolour I films used the same processing as the amateur films. I expect that the labs who processed a lot of Vericolour I probably were pro labs, with high volumes and increased quality control efforts, so a reference to Vericolour processing may have been a reference to the quality control procedures used by those labs.
 
OP
OP

spoolman

Subscriber
Joined
Sep 7, 2007
Messages
599
Location
Toronto Onta
Shooter
Med. Format Pan
Thanks Mr. Bill for that info. I remember when I worked at B.G.M. colour lab in Toronto in the mid to late 70's when we were in the process of converting from C-22 to C-41 that we kept getting film marked "Vericolour" no I,II, or III and someone pointed out that it was process C-22 not C-41. Before that, some of this film accidently made it into C-41 and gummed up the processor because of the temp. differences.

Doug:smile:
 

nworth

Member
Joined
Aug 27, 2005
Messages
2,228
Location
Los Alamos,
Shooter
Multi Format
I've never seen anything about Kodak's proprietary Kodacolor process; septim's comments are quite a revelation. The bleach used must have been similar to the bleach for black and white reversal films, removing developed silver but leaving undeveloped halide. The method of producing the mask is quite innovative. Unfortunately, the product was not so great.
 
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Ilford Photo ADOX Freestyle Photographic Photo Warehouse Stearman Press Weldon Color Lab
Top Bottom