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Re: staining in the center of a ziatype (long post)
Kathryn and all,
> Not just cyanotypes!
> I am also doing ziatypes. Although I get exasperated with the humidity
> requirements, I like the image when it's working!
>
> I'm having a problem - sometimes - with staining in the
> highlights. Generally, I get good clearing on the fringes of the image no
> matter what; sometimes I have problems clearing in the *center* of the
> image. I suspect this is due to lack of humidity control. Any
suggestions?
>
> My routine is currently: humidify the paper for 20 seconds or so, 10 on
> each side. Coat with equal parts afo, lith p generally 9 drops is what I
> need for the sheet, with a partial drop of tween and a partial drop of
> sodium tgs. Dry fairly completely with fan in reduced light, this takes
> about 3 or 4 minutes. Rehumidify about 20 seconds and expose as
> needed. I'm clearing in citric acid.
>
> The reason I like to dry to near complete-ness is because I ran into
images
> that had blurry areas... I think caused by almost-damp areas. I am not
> having this problem when I dry more thoroughly. Also, I think this
routine
> may be more repeatable in variable humidity conditions here in CO!
>
> TIA
> Kathryn
Coincidentally I have just completed two consecutive days of making
ziatypes, my first ones. First let me say that generally the process and
work flow as layed out by Carl in the New Platinum Print seem to result, for
me, acceptable results for a novice zia printer. I haven't been this excited
about printing since I first ventured into a darkroom years ago. I have to
make myself quit and go to bed. This has really been a rush.
The workflow as layed out by Carl Weese in The New Platinum Print really
helps to produce decent and somewhat predictable results. I'm using 4x5
negatives, some Polaroids and some TMAX 400 processed in trays with PMK.
These shots were specifically exposed and processed with Alt Process
printing in mind. I've printed variations of 4 negatives and all but 1 have
printed okay. 1 neg was very dense (the sky was very overexposed) and
required a 25+ minute exposure while the others are going 5-6 minutes.
My coating solution has basically been 6LiPd - 6AFO. That is the mix I've
started with for each neg. From there I have made some variants with Sodium
Tungstate and AuCl 4% sol. The TN and AuCl was added to change print color
but also to affect print contrast.
My paper has been Cranes Platine shrunk and double sized in knox gelatin and
chrome alum as outlined by the second Dick Arentz book. The light source has
been 12 20 watt BL tubes about 3 inches above the print frame.
The RH in my darkroom has ranged from 48% to 71% RH. Last night when I
entered my darkroom the RH was at 33%. To raise the humidity I ran very hot
water in my darkroom sink and that raised the relative humidty very quickly.
I then held the sheet to be coated a few inches above the water tray until I
could feel the dryness of the paper change (about a minute). I coated with a
puddle pusher and allowed to air dry for 2 minutes. Then I used a dryer on
low heat/slow air about 18 inches above the paper. The air hitting the paper
did not feel hot. After the paper was coated it tended to curl until the
emulsion was dry to the touch at which time it would "flatten" and lay down
on the coating station surface.This would occur after about a minute of
drying after the two minute soak in.
As I said generally the results are okay. I've been trying to judge the
exposure by inspection to gain experience in juding the highlight denstiy
for the POP. I usually err on the dark side. I note the print time, each
emulsion mix, and RH on the print border to help me adjust for the next
exposure. I also print a 21 step wedge with each neg to judge the print
contrast from the result of the drop mix, RH, and exposure time.
I do have a couple of questions. 1) The highlights seem to be not as bright
as I might like. I have a feeling that perhaps some of my negs may be too
dense and I'm over printing. Can the highlights be brightened? 2) The paper
surface has a fair amount of tooth. Could this be from the sizing steps?
Should Cranes be pre-soaked and sized for Zia prints? 3) Will bleaching and
redeveloping the Polaroids in PMK result in much different printing
characteristics? 4) The lower tones seem to be lumious when wet but merge
when dry (steps 1-3). I take this as normal but the seperation of lower
tones and perhaps the mid tones are not as great as I would like. Generally
the visible steps for a "properly exposed print range from 4 to 16-17. Does
this sound right?
But back to Kathryn and staining. I haven't experienced this with the
workflow listed above. I have noticed that the edges do dry last and I will
let the paper rest in a dark safe for 4-5 minutes to allow the moist feeling
of the print edges dry down. I use 1- 7 watt incandescent bulb at about 3.5
ft away from the coating station.
Thanks to all for indulging me in this long post,
Don Bryant