U of S | Mailing List Archive | alt-photo-process-l | Re: solarplate wedgies

Re: solarplate wedgies



Those look like marks related to not using enough pressure in the press. I get them sometimes too, and when I do, I either have to crank down the pressure on the press, or run it through the press twice (or both) -- once through and then back. Similar patterns sometimes show up due to the blankets if they're too coarse. I usually put a sheet or two of newsprint on top of the paper before putting the blankets down and running it through the press to ensure patterns from the blanket don't get into the print.

How big is the drum on the press you're using? I used to use an abused little Takash press with a 5" drum. Turns out due to the drum size and/or wear and tear on it, it simply inadequate for printing poly gravure. I switched to a press with a 10" drum and rarely have this problem now, except occasionally when I'm printing full A2 sized plates.

Hope that helps!

Jon

SusanV wrote:
Hey Jon,

Go look at my blog.  All the way down at the bottom of the page there
are images of a step wedge showing the speckles.  They aren't large
areas of tonal difference... they're small "squiggles" of lighter tone
that show up mostly in the mid to lights.  I think the darker tones
just mask them though, because those areas are holding more ink, and
it gets smeared around on the tops of the light spots and doesn't get
wiped off.


susan
gravure blog at www.susanvossgravures.blogspot.com
website www.dalyvoss.com



On 4/4/07, Jon Lybrook <jon@terabear.com> wrote:
Hi Susan,

Can you post a scan of the irregularities?

Thanks,
Jon

SusanV wrote:
> Well I got mixed results.  It (acetate as described below), eliminated
> any visable newton's rings, but darnit I still have some very
> small-scale irregularities of tone that I just don't understand.  It's
> much better than it was however, so I'm not toooo discouraged.
>
> Susan
>