From: Joachim (joachim@microdsi.net)
Date: 04/12/00-03:08:43 PM Z
A few observations regarding AZO paper since the recent article by Michael
A. Smith in March/April "View Camera": I have used it for years with an
ancient contact print box. It has all the dynamic range Ansel Adams raved
about. Its longer shelf life is surely related to the slow photic reaction
of silver chloride, the thing that makes it ill-suited for enlarging and
which provides its wide tonal range. The two distinct disadvantages are the
tendency of the paper to crinkle, requiring drymounting and a dry press, but
more significantly the prints have a somewhat nauseating greening color.
The latter can be readily overcome by toning (selenium, usually) and the
prints tone very readily and also split tone beautifully. These
disadvantages are obviously not insurmountable. Bromide enlarging papers
are fast, chlor-bromide a compromise between fast bromide and slow chloride.
Contact printing is less flexible than light controls in enlarging, but some
degree of control is possible in a print box by turning lights off
selectively and using masking materials. Tonal range flexibility with AZO
can be achieved to some degree in development (Selectol Soft, for example)
but AZO contact, more than enlarging papers, demands a very good negative.
JOACHIM
> -----Original Message-----
> From: Richard Maddox [mailto:slow_emulsions@yahoo.co.uk]
> Sent: Tuesday, April 11, 2000 10:13 AM
> To: alt-photo-process-l@sask.usask.ca
> Subject: Re: Kodak Azo Paper Question
>
>
> Uh,
> Do you have the sheets for grades '0', '4' and '5'?
> these are the ones I am missing. Since it was '43-'46
> that you mentioned, perhaps the curves for all 6
> grades are on one data sheet.(?)
>
> "...the old Kodak Reference Handbook",
> Is this the title? When was it published?
> Is it the same thing as the Kodak Data Guide?
>
> --- Richard Knoppow <dickburk@ix.netcom.com> wrote:
> > It should be kept in mind that a negative will
> > print more contrasty on a
> > condenser enlarger than it will on a contact printer
> > or diffusion enlarger.
> > The difference is about a paper grade. A negative
> > which prints right on #2
> > paper on a condenser enlarger will need #3 paper to
> > have the same contrast
> > when contact printed.
>
> Good point.
>
> But would you really expect to see the same amount of
> contrast loss with the contact printer? Perhaps so, I
> just thought the contact print would have a bit more
> contrast than the diffusion enlargement....
> My powers of reasoning are on strike most of the time,
> so would you entertain this purely theoretical
> question...how does contrast change with increasing
> enlarging distance? I am thinking that it must
> decrease, since there is light loss from both
> highlight and shadow areas, but once the shadows are
> depleted, contrast has no where to go except down.
>
> If this is so, is it an issue someone enlarging would
> ever have to deal with? Perhaps some one who has made
> a number of very small and very large prints from the
> same negative would have noticed if contrast was
> affected or not.
>
> Does your information hint at any difference between
> earlier AZO version(s) and the AZO available today?
> I belive what I might have been thinking... was that
> perhaps AZO has changed over this century, growing in
> speed and perhaps with changes in its contrast...
> reflecting changes in the type of negatives which were
> being made....
>
> Just curious,
>
> RM.
>
>
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