[ARC5] WW II Aircraft factory pictures

[Bob Macklin]

I got on to Ektachrome when I was using 120(6X6) TLR cameras.

Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"
----- Original Message ----- 
From: "J. Forster" <jfor at quikus.com>
To: "Richard Knoppow" <1oldlens1 at ix.netcom.com>
Cc: "Bob Macklin" <macklinbob at msn.com>; <jfor at quikus.com>; "Christopher 
Bowne" <aj1g at sbcglobal.net>; <arc5 at mailman.qth.net>; "Clare Owens" 
<clare.owens at gmail.com>
Sent: Sunday, February 17, 2013 12:00 PM
Subject: Re: [ARC5] WW II Aircraft factory pictures


> My belief has always been that Ektachrome was the better film for natural
> color rendition. IMO, Kodachrome produced "WHAM, POW, SOCK" cartoon-like
> images.
>
> YMMV.
>
> -John
>
> ======================
>
>
>
>>
>> ----- Original Message -----
>> From: "Bob Macklin" <macklinbob at msn.com>
>> To: "Richard Knoppow" <1oldlens1 at ix.netcom.com>;
>> <jfor at quikus.com>; "Christopher Bowne" <aj1g at sbcglobal.net>
>> Cc: <arc5 at mailman.qth.net>; "Clare Owens"
>> <clare.owens at gmail.com>
>> Sent: Sunday, February 17, 2013 9:48 AM
>> Subject: Re: [ARC5] WW II Aircraft factory pictures
>>
>>
>>> My memory of Kodachrome says that Kodachrome was only
>>> processed by Kodak labs?
>>>
>>> I have been using Exctachrome for slides for may years.
>>> Still have 6 rolls in the fridge.
>>>
>>> Bob Macklin
>>> K5MYJ
>>> Seattle, Wa.
>>
>>      Kodak originally processed Kodachrome only at the
>> factory at Rochester, N.Y. After about a year a simpler
>> method of processing was devised and Kodak established
>> processing stations in other cities.  I think eventually
>> there were about four.  Sometime in the 1960s (by memory)
>> Kodak was sued for restraint of trade because they included
>> the cost of processing in the price of the film. They had to
>> stop this practice but at about the same time begain to
>> license independant laboratories to process Kodachrome.
>> Kodak supplied the machinery and chemistry since, even with
>> simplification of the original proces, it was still complex
>> and difficult to control.  Kodak had a vested interest in
>> maintaining the quality of the results so was pretty careful
>> about the independant processors.  Kodak also continued to
>> process the film in their own labs.
>>      Kodachrome is a three layer film but the "couplers" or
>> dye intermediate chemicals are not included in the layers.
>> This was because Kodak could not find a way of
>> "sequestering"  them to keep them from wandering into the
>> wrong layer.  So, the couplers were put into the reversal
>> developers.  The film was developed to black and white
>> silver images in all three layers then re-developed in three
>> separate reversal baths to generate the color, the silver
>> being removed after processing.  It was the method of
>> insuring the right color would appear in the right layer
>> which was changed from the early to the later processing
>> method.  The original method, which  I beleive was used only
>> for about a year, required the controlled penetration of a
>> bleach into the developed film.  After the initial B&W
>> processing the film was developed again in a bath with the
>> coupler for the bottom layer, this produced color dyes in
>> all three layers. It was then floated on a bleach bath which
>> bleached the color out of the top two layers then developed
>> again in a bath with the coupler for the center layer. Then
>> the top layer was bleached out and developed with the proper
>> coupler for the color there. In between these steps the film
>> was washed and _dried_. The drying was done to control the
>> rate of up take of the bleach bath.  After about a year
>> another method was devised; this one used differential
>> re-exposure and made use of the remaining color sensitiivty
>> of the layers.  It still took three re-development baths but
>> the bleach steps were eliminated.  After this method as
>> adopted Kodachrome became available in many formats other
>> than 16 mm film.  Up to about 1948, when Ektachrome was
>> announced, Kodachrome was made in sheet sized up to 16x20
>> inches!  All the larger films were processed in Rochester.
>> Commercial and advertising photographers who had come to
>> rely on Kodacrhome were very upset at its discontinuance in
>> sheet sizes because Ektachrome was thoroughly inferior.
>> Ektachrome had the advantage that any commercial lab could
>> ste up to process it although it was still quite fussy.
>>      Kodak had discovered a method of sequestering the
>> couplers in the early 1940s which was used first for
>> Kodacolor and its print paper. The color was inferior to
>> Kodachrome but the processing was much easier.  At about the
>> same time as Kodachrome was announced AGFA had come up with
>> a multiple layer color film but using incorporated couplers.
>> They had come up with a different method of sequestering the
>> couplers than Kodak used.  Agfacolor was not sold outside of
>> Germany and most seems to have been used by the government.
>>      Both methods of sequestering the couplers continued to
>> be used for decades, I am not sure which method survives.
>>
>>
>> --
>> Richard Knoppow
>> Los Angeles
>> WB6KBL
>> dickburk at ix.netcom.com
>>
>>
>
>
>