Re: pigment

I'm going to throw out something here you all can hash over.

I don't use Prussian blue just because of some brands' purported fading in
sunlight and recovering in the dark...Maimeri, Sennelier, Schmincke, Wand
N...

Page says she has not seen it recover.

Whether this is fact or fallacy, thalo works so much better with more color
saturation and clearer and smoother. But it seems to me that this chance
would be akin to working with Alizarin nowadays when there are better,
permanent reds.
Chris

----- Original Message -----
From: "Jack Fulton" <jefulton1@comcast.net>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Monday, November 21, 2005 10:15 PM
Subject: Re: pigment

> Yes, the 'blue' of the cyanotype is Prussian Blue. The cool thing about
> it is that it was the first true blue that was what one might call
> inexpensive. It came around in the early 1700's, so Herschel knew all
> about it when developing the cyanotype.
>
> One interesting anecdote for today's climate of terrorism is that
> Prussian Blue and Potassium Iodide can be ingested to aid in the removal
> of radioactive materials from the body. Both of these are chemicals of
> our medium. The FDA approval of Prussion Blue is either coming up or was
> recently approved. The U.S. is stockpiling capsules of it.
> Jack Fulton
>
>
>
> On Nov 21, 2005, at 8:49 PM, Katharine Thayer wrote:
>
>>
>>
>>
>> On Nov 21, 2005, at 6:55 PM, Dave Rose wrote:
>>
>>> Isn't Prussian Blue the same pigment/chemical that forms cyanotype
>>> prints?
>>
>> Is it? I guess I've never heard or thought about what the final product
>> is that forms a cyanotype print, but Prussian blue is hydrous ferric
>> ferrocyanide or feriammonium ferrocyanide, is that what it is?
>>
>> To my eye, Prussian blue pigment has a greener cast to it than most
>> cyanotypes I've seen, or than pthalo, which to my eye has probably the
>> purest cyan hue for tricolor of the blue pigments available, followed by
>> ultramarine. And to me it's a duller blue than either pthalo or
>> ultramarine, and for those two reasons I didn't suggest it for tricolor.
>> But I can't say for sure that it's not good for tricolor, because I've
>> never tried it. I guess I was also influenced by someone who wrote the
>> other day that he had tried Prussian for tricolor and it didn't work
>> well at all.
>>
>> I feel another test
>> kt
>>
>
Received on Tue Nov 22 08:09:39 2005