Re: Brush Marks on Platinum/ Pd. prints

John Rudiak (wizard@laplaza.org)
Sun, 05 Apr 1998 19:01:08 -0600

Jeffrey D. Mathias wrote:
>
> > Stephen R Harrison wrote:
> > >
>
> John Rudiak wrote:
>
> > Hey Stephen- what do your "brush marks" look like?
>
> ...
>
> > While you are using almost twice the amount of sensitizer than I do on
> > 12X20's,
>
> ...
>
> > Maybe you are abrading the paper by pushing the sensitizer around
> > for too long a time period. ... If you
> > are brushing long enough for it to start to dry that could very well be
> > the cause of problems.
> >
> > This assuming the paper itself is not at fault.
> >
>
> Stephen,
>
> John makes some good points. However, as to the amount of solution, I also would
> use 72 drops per 12x20. The reason is that I have found that less chemistry
> seems to give less "depth" in the print. Of course different papers will require
> different optimum amounts of chemistry. I recommend you stay with the 72 drop
> amount. It is far better to go for the best print possible than to save a little
> money.
>

I believe he said 4.5ml. of A and 4.5ml of B. that's 9ml per 12X20. As
far as the 72 drops, he said equivalent (I measure 20 drops per ml in my
lab) but because he said eqiuvalent I assume he is using a pipette for
measurement and using 9ml per print. Anyway I don't think this is the
problem.


> As to your problem:
> a) it is difficult to analyze without seeing the "brush marks" (if that's what
> they are).
> b) try a different paper, preferably one you know works well.
> c) do not abrade the paper and do not let coating dry while coating (work
> quickly, this becomes more difficult the larger the print, practice).
> d) both too thin or too thick a coating may cause marks in final print.
> e) view the problem print on a light table; check dark areas as well as
> highlights.
> f) wait until coating appears dull (not glossy) before hitting with blow dryer.
> g) apply only a single coat; once coating is dry, do not touch, especially with
> anything wet.
> h) also, check your brush for old converted chemistry; if bad use a new one. It
> is good practice to always rinse the brush well with distilled water after the
> coating session; and keep brushes stored in the dark.
>
> Hope this all helps.
>
> Jeff

-- 
ÿWPCÛ