U of S | Mailing List Archive | alt-photo-process-l | Re: Tacky attraction

Re: Tacky attraction



yet another thought:

So the polymer is placed under a vacuum.  It is entirely possible that
doing that actually pulls air out of the polymer itself, causing the
air pockets under the ohp.  The stuff is water soluble, and not rigid,
so I would BET that it is porous and contains air and water = vapor.

solution:  place the plate alone, under vacuum (no light), for a
couple of minutes prior to exposure to evacuate any air that wants to
leave, THEN do the positive exposure.

who knows... maybe, maybe not.

(In fact, the heat of a longer exposure might even exacerbate such a
phenomenon.)

susan

On 2/28/07, SusanV <susanvoss3@gmail.com> wrote:
::::::::: smacking self in forehead :::::::::::

susan

On 2/28/07, taylordow <taylordow@sprintmail.com> wrote:
> Susan,
>
> Trim the film! I cut mine so that I have just the image - not even a
> clear border. If I don't trim it down to less than the plate size, I
> always get contact problems.
>
> Keith.
>
>
> On Feb 28, 2007, at 12:09 PM, SusanV wrote:
>
> Hello,
>
> Another day, another idea...  I haven't been cutting my positive films
> to match the outside edge of my plates.  I've just been letting the
> excess hang off all around the edges.  That "hangover" gets pulled
> down by the vacuum pressure, probably creating a tight fit along the
> perimeter of the plate, further hampering the attempted exit of
> terrified air molecules.
>
> The little test strip I tried yesterday didn't measle.  The ohp film
> was actually a little smaller than the plate.
>
> note to self:  trim those films.
>
> susan
>
>


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


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