oops... Keith just said that :o) Looks like the gang's all here this morning.
susan
On 4/8/07, SusanV <susanvoss3@gmail.com> wrote:
> Oh, and warming the plate is common when working with copper or zinc
> printing plates. it makes the ink "melt" into the surface and move
> around easier. I've been afraid to warm the polymer ever since I
> melted some in the oven trying to warm-dry it. I do however, work my
> ink on a warm surface sometimes... been experimenting with that. I
> use a large ceramic tile, and sometimes I warm it with a hot pad under
> it. Not so sure it's worth the trouble though unless the studio is
> especially cold.
>
> Susan
>
> On 4/8/07, SusanV <susanvoss3@gmail.com> wrote:
> > Hey Chris,
> >
> > thanks for taking time to post this info! Very interesting stuff. I
> > look forward to someone jumping in here to translate... one of the
> > many nice things about this list :o)
> >
> > susan
> >
> > On 4/8/07, Jon Lybrook <jon@terabear.com> wrote:
> > > \Christina Z. Anderson wrote:
> > > > 2. Exposing is done in 3 stages--main exposure first for **15**
> > > > minutes with the light source at 1/2 the distance of the aquatint
> > > > exposure. Aquatint exposure SECOND--**15** minutes with the distance
> > > > of the light 1 1/2 the diagonal of the vacuum frame measure. Post
> > > > exposure 5 minutes. (on a Stouffers dark steps 8, 9, and 10 should be
> > > > "clearly defined").
> > > Maybe he's using a maglight to make his exposures. ;-)
> > >
> > > > With the inverse square law of light 1/2 the distance of the positive
> > > > means it is 4x the length of exposure, correct? So Ponsaing's ratio
> > > > of exposure is 4pos/1aquatint. Can you believe the length of his
> > > > times??!! I can't read the text to see what his light source is,
> > > > though, unfortunately. I can glean that he is using Japanese plates KM73.
> > > >
> > > > Oh, here are his light choices: "uv lys, kviksolvdamplampe hpr 125,
> > > > drosselspole bhl 125 eller l44, metalhalogenhampe, xenon lampe. And
> > > > then Ikke alle lyskilder er egnede til vor kopiering. Der kraeves
> > > > lysbolgelaengder mellem 400-360 my i det ultraviolet-te omrade af
> > > > spektret. Ved anvendelse af FP-plader til dybtryk, er punktlys bedst
> > > > egnet, d.v.s. at lyskilden har sa lille en udstraekning som muligt.
> > > > Dette lys findes i kviksolvdamplampe, hojfjeldssol, xenonlampe,
> > > > metalhalogenlampe og kulbuelampe.
> > > >
> > > > My interest in the light source choice is to compare his longer
> > > > exposures with what we are doing with KM73s. What he is doing is
> > > > still not disproving my theory that the length of exposure is not as
> > > > crucial as the ratio, unless, say, he is using REALLY weak bulbs which
> > > > I don't think is true--I can at least decipher halogen in there. But
> > > > it still supports the theory that, like gum, the longer exposure (to a
> > > > point) the thicker the layer of goo on top of the substrate, whence
> > > > comes Welden's description of the forgiving latitude of exposure of
> > > > the plates, that exposure is not so crucial.
> > > So based on your theory Chris, if my ratio is 1:1 screen/image, I could
> > > do 10 seconds/ 10 seconds, or 1min/1min, or 15min/15min and it wouldn't
> > > make a huge difference? This might be true to some degree if one is
> > > using imagesetter film for both, since the density of imagesetter film
> > > is so heavy. I'd expect the dots would change size as time is
> > > increased though, since the longer exposures would allow more light to
> > > sneak underneath the edges of the dots. Easy enough to test
> > >
> > > Thanks for the posting!
> > >
> > > Jon
> > >
> > >
> >
> >
> > --
> > susan
> > gravure blog at www.susanvossgravures.blogspot.com
> > website www.dalyvoss.com
> >
>
>
> --
> susan
> gravure blog at www.susanvossgravures.blogspot.com
> website www.dalyvoss.com
>
--
susan
gravure blog at www.susanvossgravures.blogspot.com
website www.dalyvoss.com