[alt-photo] Re: gum speckles

[Loris Medici]

Hi Matt, if everthing else is the same (emulsion pigment exposure
development etc.), and it's not a paper/sizing issue as Henry points
out, then I'm with Diana; could be something related to humidity.
Raised humidity level may lead to overexposure and overexpose may lead
to increased development times and flaking/speckling. ???


On 18 Kas 2011, at 23:31, Henry Rattle <henry.rattle at ntlworld.com> wrote:

> Matt - not sure if it is helpful, but I have had the odd sheet of paper (once, just one end of a sheet) where the factory sizing was uneven or incomplete so my added surface size became speckly too. The effect in my case was coloured speckles where pigment didn't clear, though I guess you could get the opposite effect where it washed off completely leaving those white marks. These were sheets of paper from an otherwise perfect batch.
>
> Let us know when you solve it! Best wishes Henry
>
> Sent from my iPhone
>
> On 18 Nov 2011, at 20:31, Diana Bloomfield <dhbloomfield at bellsouth.net> wrote:
>
>> I don't know, Matt.  Whenever I've had anything resembling anything close to that, it was from using too much pigment.  That speckling is so consistent, though, it almost seems like the substrate was really really textured.  But since you're using the same paper and have had no previous problems, my bet is on too much pigment.  Of course, there's always humidity issues.
>>
>> I'm sure somebody else will chime in, though, with something more helpful (unless we're the only people reading this list today). I have used certain pigments, too, that don't work as well as others.  I assume you're using the same amount, same pigment, with no previous problems.
>>
>>
>> On Nov 18, 2011, at 2:36 PM, Willen, Matthew S wrote:
>>
>>> Sorry about that folks, didn't realize I couldn't send an attachment. A sample of the gum speckling can be viewed at:
>>>
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