Re: Your print on Al
Loris,
You have burnt midnight oil in responding to my request and I thank
you for all the detail you provide.
It might take me a while to shift from the familiarity I have
developed with Masa (which I am using for my current project on Still
Life), before I set up and shift to Al. But I have every hope of
doing so for the time and trouble you have taken to so generously
inform the list and me.
Many thanks and I look forward to seeing the outcomes of the passes
on your premier Al opus.
Best wishes, Rajul
On 3-Mar-09, at 1:21 AM, Loris Medici wrote:
Dear Rajul, I will cc this to the list also (it may be useful for
others
too)...
Negatives:
I use a thin paper for the negatives; it's Keith's infamous "18lb
Translucent Inkjet Bond" from Freedompaper. I print my negatives
with a
HP9180 printer, using "Gray Only" inks. I use a simple curve
(actually no
curve, just levels adjustment, which is applied to the positive,
not to
the negative), which was derived by printing a 101 step tablet at
standart
exposure time (which was determined not by testing, but by feel!) and
adjusting the gamma slider so that the reading from the printed 18%
gray
patch matches the reading from the original file at the same location.
Actually, not much critical with gum; as you have so much play in
coating
solution formulation, exposure, development, and whatnot...
Most info below comes from my exchanges with Keith:
To prepare the sheet I first mix 25g acrylic gesso + 50ml water + 50g
calcium carbonate powder thorougly (you may also replace 10g calcium
carbonate with 10g titanium white to get a whiter base and slightly
less
absorbent ground), then I add further 50ml water (stir/mix thoroughly
again) to dilute the mixture for easy application. I apply the
mixture to
the cleaned / degreased (with rubbing alcohol) sheet using a 5"
foam paint
roller. I quickly dry the first layer with a hairdryer at hottest
setting
and apply a second layer (using the roller at a perpendicular angle
to the
previous layer). I repeat this until I have 4 layers (always altering
directions). The criteria/purpose is to have an even and opaque
layer. I
leave the sheet to dry thoroughly for a day or two, then I prepare
a 1.5%
gelatin solution (w/ 0.5ml formalin) and apply this to the sheet. It's
ready to print on after the gelatin dries and hardens. You may opt
to sand
the surface for a smooth finish, since the texture is quite pronounced
when coating with a foam roller.
Side info:
I use 5% ammonium dichromate as sensitizer. My coating solutions
consist
of 1:1 gum/pigment:dichromate. I expose the sheet for 12 minutes (base
exposure; may differ dependint to pigment/sensitizer strenghts and
intent.
I use 40W 24" UVBL tubes BTW...) and develop face up for 30 - 40
minutes.
Agitating the tray and changing water every 10 minutes.
For obtaining the sheets:
I obtain my sheets from specialized wholesale stores. I use 0.3mm (28
gauge / 12mil) thick sheets which come at 1x2m (39 3/8x59") size. I
have
them cutted to size for few extra bucks at a near workshop. The whole
sheet + cutting will cost about $15. That is $1 per 13x15 6/8"
sheet (for
instance); comparable to fine watercolor paper, with the added
bonus of
being an ultra-quick drying material/surface which is also very
durable
(much more than paper) and recycleable - just coat another ground
layer
over a bad print or use the back side since it's exactly the same,
unlike
most papers... I can't speak for / suggest anything for your case,
since
we're in very different environments (Turkey <--> US?)...
Hope this helps,
Loris.
2 Mart 2009, Pazartesi, 1:15 am tarihinde, Rajul yazmış:
Hi Loris!
I am writing to you after a long time! I must tell you how far I feel
this medium will take you and your negatives in the
days to come. You have probably hit a mine.
I would very much like to know how you produce your large paper
negs. I also would like to have a go at printing on Al sheets and
would appreciate details of the type of media you work on (where you
obtain it) and how you prepare the surface.
I have very much enjoyed working on Masa and it was worth all the
trouble taming it. Once mounted on to a support, it takes pretty
harsh treatment and at least 4-6 passes!
Many thanks for any info you can provide on Al.
Rajul
|