Author Topic: DEDUCING COLOURS FROM B/W PHOTOS  (Read 920 times)

Offline GHE

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DEDUCING COLOURS FROM B/W PHOTOS
« on: October 31, 2012, 03:46:41 AM »
Meine Herren !

Deducing colours from b/w is possible but does not come easy.

A b/w material translates colour rays into grey tones.
Ortho- or Panchromatic material does show a given colour in a given grey tone/hue.
The significant influences on this tone are shutter speed, lighting conditions, development conditions for film and(!) paper copy
and the use of optical filters to influence they grey tone / enhance a certain grey tone etc.(they could be used during the developing process, too!!)

So just deducing from the panchromatic (1906) material would be easy; you just have to find out how this material usually rendered colour.
Then one may say: this was a yellow tone.
But you still will not know, what yellow hue.
Therefore one has to gather knowledge on the then used paints etc.

The filters/lighting condition / shutter speed - influence is a hard nut to crack; it severley changes the defined panchromatic
grey tone.

In the end one may get close and it is a real scientific work and worth it, but does not come easy.
The computerized colouring of b/w-films  ("WW I in Colour") is just nice.

Very correct indeed was the Autochrome Process, delivering very good colour representations, maybe even better, than Kodachrome 64 or AGFAchrome.
Imagine: real colour photography, not b/w photos painted afterwards with albumin transparent varnish paint !

I think no one really has researched how many  WW I autochromes survived on military items.
As a tit-bit I recommend the BBC series -available in print and DVD on the French Banker Kahn ( who wanted to do a complete photostory of the whole world in autochrome colour); at least some WW I frames are shown!

viele Gre, Gunther
« Last Edit: October 31, 2012, 04:00:03 AM by GHE »
LZeppelin rocks!

Offline Checkers67

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Re: DEDUCING COLOURS FROM B/W PHOTOS
« Reply #1 on: October 31, 2012, 11:59:56 AM »
Kodachrome was light years ahead of autochromes! Actually decades.  8)
Steve

Offline GHE

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Re: DEDUCING COLOURS FROM B/W PHOTOS
« Reply #2 on: October 31, 2012, 10:11:30 PM »
I loved this film in the pre-digitalisized days !
Kodachromes at home some 60 years old now - of course stored well - still look pristine !
AGFAchromes deteriorate due to the processing method.

The interesting thing on the autochrome slides is, that the way they were made one does not assume that they produced
very correct colours.

Until now I did not find a way to  digitally reproduce this charming effect

viele Gre, Gunther

« Last Edit: November 01, 2012, 11:35:17 PM by GHE »
LZeppelin rocks!