View Single Post
  #24  
Old December 31st 06, 02:35 AM posted to rec.photo.equipment.large-format
Richard Knoppow
external usenet poster
 
Posts: 751
Default morse contact printers


"Richard Knoppow" wrote in message
ps.com...

Richard Knoppow wrote:
"Nermal" wrote in message
news
I have used one of these for printing-out paper. The
exposure time was 2 - 5 minutes. The heat build up
during
the exposure time was minimal. I also printed to blue
print
paper.

If I had one of these things now, I would print some of
my
old negatives to a home made silver chloride coated
paper.



Richard Knoppow wrote:
"Thor Lancelot Simon" wrote in message
...


I am very surprized that you got this result. My
experience with printing out paper is that it requires a
few
minutes in direct sunlight. The intensity of my Morse
printer is very much below this. They were intended for
printing aerial camera negatives on rather slow contact
paper, something like Azo, with a few seconds exposure
time.
The lamps are very low power Argon lamps. BTW, I found a
bunch of the lamps at a ham radio swap meet a couple of
months ago for a dollar each! I don't think the guy
selling
them knew what they were.


--
---
Richard Knoppow
Los Angeles, CA, USA


I will try this. I have experimented in the past with
photolytic
images from sunlight on conventional printing paper. They
are not
strong but appear. it will be simple enough to try it
with the
printer.
I wonder if we are talking about two different kinds of
printers. I
don't know if Morse ever made plate burners but what you
describe
sounds like it might be one.

Richard Knoppow


Well, I tried this and was astonished to find it worked!
I tested with a sheet of enlarging paper placed on the inner
diffusing glass with some opaque cardboard under half of it.
I gave it ten minutes. The exposed end was quite purple. I
didn't use the top glass plate because it is not original on
my printer and has significant UV absorption. I presume the
original plate was clear glass rather than green glass with
much greater UV transmission. The attenuation of UV on mine
is probably actually an advantage since exposure time is
very short.
Previous experiments with photolytic printing using
ordinary developing out paper suggest that the Morse printer
_would_ probably print POP in a few minutes. POP is still
made by Kentmere in England and sold in the US under the
Centenial POP name. For those not familar with POP it is
printed directly in sunlight. The image is not permanent
unless treated in toner and fixed. The original image color
is a sort of purplish brown but it can be toned to many
colors.


--
---
Richard Knoppow
Los Angeles, CA, USA




--
Posted via a free Usenet account from
http://www.teranews.com