U of S | Mailing List Archive | alt-photo-process-l | Re: polymer plate drying time

Re: polymer plate drying time



Oh Susan (O'Flaherty O'Daly),

Yes, I have been getting the same dark patterns if I don't use baby
powder or spray and maintain a long drawdown time (image only, not
screen).  I'm building a little drying box today and will be at the
studio this afternoon to see if that helps more.

Jon


On 3/17/2007, "SusanV" <susanvoss3@gmail.com> wrote:

>Jon and Keith,
>
>Thanks for this discussion.  Lots of helpful information.
>
>I rigged a striplight under my exposure head so that now I can really
>watch the positive as it gets sucked down against the plate.  What I
>see are lots of little irregular shaped areas that move and change
>shape, and they're colors are rainbow-like and change... I think it's
>a Newton's rings kind of thing.  (and no I haven't been smoking
>anything :P )  The shapes are larger in the beginning, then get
>smaller but more numerous as the vacuum continues.  This is SO hard to
>describe, haha.  Do you all see anything like that happening?
>
>I'm snowed in here and happy as a clam to be heading to my studio for
>a day of printing!  Will definitely be drying my OHP now.  I'm going
>to find one of those bonnet hairdryers this week and try out using it
>to rig a drying box.
>
>Happy St Patrick's Day!!!
>
>Susan O'Flaherty O'Daly  (my real family names 2 generations back :o) )
>
>On 3/17/07, Jon Lybrook <jon@terabear.com> wrote:
>> More questions and responses below...
>>
>> Keith Taylor wrote:
>> > Jon,
>> >
>> > I remove the Mylar and dust with talc (screen and positive).
>> Do you use actual talc, or baby powder?  I've found that real talcum
>> powder is difficult to find - though I used some in Florence.  Much more
>> chalky and coarse than baby powder -- at least the batch I had access to.
>>
>> > I have a 33x43" vacuum frame with glass, get 22in Hg and I leave it
>> > for at least 3 minutes before exposure. I have a ribbed bed to the
>> > frame which causes problems with platinum prints, so I have a sheet of
>> > black plastic 1/32" thick.
>> The Kreene makes it so I can only get about 12 in the vacuum frame.
>> Images are generally pretty sharp except for the patches though.
>> >
>> > You use an anti-static spray regularly don't you?
>> Yes, due to the Kreene plastic.
>>
>> > I clean the glass with a non-ammonia, non-alcohol based cleaner, but
>> > no anti-static spray. I also use Pictorico on a roll (never sheets)
>> > with an Epson 4000. I do have a 2200 that I use infrequently with
>> > sheet Pictorico, but not for gravure - usually small platinums.
>> > I dry the OHP in the film drying cabinet for 20-30mins low heat prior
>> > to use.
>> Drying the OHP seems to be the biggest difference, since I used to have
>> glass in my vacuum frame, and do basically everything similarly to
>> you....but I've never bothered to try drying the OHP with heat for 20-30
>> minutes.  I did use to dry my plates with a hair drier until I was told
>> by an instructor that it was a waste of electricity...NOT.
>>
>> >
>> > I'm just throwing out things here that you may recognise as being
>> > different from your setup.
>>
>> Thanks Keith.   I'm very eager to dry some OHP and try dusting again,
>> both the plate and positive and will report back.
>>
>> Best regards,
>> Jon
>>
>>
>
>
>--
>susan
>gravure blog at www.susanvossgravures.blogspot.com
>website www.dalyvoss.com
>
>