(no subject)

 
 
 
Loris
 
I made it clear that the rex preocess has such latititude that the single
comparison you suggest is inappropriate. But if that is the comparison you
want, the same density can be obtained with the rex process after an exposure of
one minute where the equivalent for the original process would be thirty
minutes or about five stops.
 
 
Terry
 
 
 
 
 
In a message dated 16/02/2006 06:10:21 GMT Standard Time,
mail@loris.medici.name writes:

If you remember, in my very first message to you I requested a speed
comparison in terms of stops. You can direct scientific tests similar to
those made by Sandy King while he was evaluating different lightsources
for alternative processes. See
http://unblinkingeye.com/Articles/Light/L2/l2.html

It's easy: just print a Traditional Cyanotype step wedge showing steps 1
and 2 merged to dmax, do the same for Cyanotype-Rex (using the same
artificial lightsource for both test) and note the exposure times. This
will give you the speed (exposure time) and contrast (printed steps)
difference between the emulsions in a very scientific and exact manner.

Will you be kind enough to do this test and share the results with us?

TIA,
Loris.

Terry King FRPS

RPS Historical Group (Chairman)

_www.hands-on-pictures.com/_ (http://www.hands-on-pictures.com/)

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Received on Thu Feb 16 02:02:25 2006