U of S | Mailing List Archive | alt-photo-process-l | Re: gum negatives redux

Re: gum negatives redux

Sorry, I can't help with amounts (besides, amounts will vary by brands, since brands vary widely in their degree of pigmentation) because like a painter, I mix to a particular "look" rather than measuring the pigment. When it's the right dark, then it's right. To my mind, this is the only reasonably accurate, sensible and reliable way of mixing pigments, but everybody has their own thing that works for them. It's really something you have to get a sense of by trial and error, sorry.

On Sep 14, 2009, at 9:23 AM, Paul Viapiano wrote:

OK...more pigment than 1 gr to 2 ml ?

You see, I guess I don't know what a good general ratio is for high, mids and lows. I know pigment varies, colors vary, etc but I'll figger it out...

Thanks, Katharine...much appreciated...


----- Original Message ----- From: "Katharine Thayer" <kthayer@pacifier.com>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, September 14, 2009 9:12 AM
Subject: Re: gum negatives redux

Sorry I'm late here; I was busy on a different project.

I'd say you didn't expose it long enough; it should be of course exposed at least enough to retain DMax, which it doesn't sound like this was.

And no, I wouldn't say you should expect a much shorter development when exposing for the shadows;. in order to express the detail in the shadows it needs to be developed enough to open the shadows and to release any of the darker pigment from the lighter midtones and highlights.

Ivory black is also a much weaker pigment than some of the other blacks, like lamp black; you'd need to use more pigment to get a good dark. Hope any of that is useful,

On Sep 13, 2009, at 4:24 PM, Paul Viapiano wrote:

Katharine & Jim...

I tried the ivory black at 1 gram / 2 ml gum in a 1:1 ratio with the pot dichromate.

Exposed for approx half my highlight exposure, but at 25 min in development, there was hardly any black pigment left on the print.

I need to step-tablet this negative and try a few different pigments...but...

When doing an exposure for the shadows, would you expect a much shorter dev time?


----- Original Message ----- From: "Katharine Thayer" <kthayer@pacifier.com>
To: <alt-photo-process-l@usask.ca>
Sent: Saturday, September 12, 2009 6:17 PM
Subject: Re: gum negatives redux

Suggestion: I'd use ivory black, not too heavy (at a medium- heavy concentration, it's a lovely dark chocolate brown color, the color of bittersweet chocolate) to fill in the shadows; that would anchor your image well, IMO.

The pigment concentration should vary with the pigment, but what you're done here looks okay to me. The earth pigments are weaker as a rule than some others, but your burnt umber looks good there for midtones. You'll never be able to print the burnt umber dark enough to really give dark shadows, it's not in its nature, which is why I'm suggesting ivory black for the darker parts.

Glad you're having a printing day that doesn't require chugging the Everclear,

On Sep 12, 2009, at 5:54 PM, Paul Viapiano wrote:

1st layer: Burnt umber 5 1/2 minutes

2nd and 3rd layers: Raw umber 2 1/2 minutes (1 gr pigment / 2 ml gum) Is this concentration high enuff?

I think 2 1/2 min is not enough time with these Pd negs...I'm thinking 3 1/2 m


----- Original Message ----- From: "Katharine Thayer" <kthayer@pacifier.com>
To: <alt-photo-process-l@usask.ca>
Sent: Saturday, September 12, 2009 5:30 PM
Subject: Re: gum negatives redux

Yeah, I'd say hit it with a really heavy pigment concentration for a short time for darker shadows. What's your pigment?

On Sep 12, 2009, at 5:00 PM, Paul Viapiano wrote:

Well, not finished yet...needs some more shadow work...but...


----- Original Message -----
From: Jeremy Moore
To: alt-photo-process-l@usask.ca
Sent: Saturday, September 12, 2009 4:34 PM
Subject: Re: gum negatives redux

Any scans or shots of the images? There has been a dearth of new alt prints in my life as of recent.

On Sat, Sep 12, 2009 at 2:42 PM, Paul Viapiano <viapiano@pacbell.net> wrote:
I should've been more clear...I'm getting better gum results from palladium negs than using less contrasty negs for gum. My palladium prints print wonderfully with the palladium negs ;-)

This would be a huge advantage for me, in not having to keep track of two different styles of digital negatives.

Now, I'm wondering how the palladium negs will work with tri- color gum...only one way to find out!


----- Original Message -----
From: "Paul Viapiano" <viapiano@pacbell.net>
To: <alt-photo-process-l@usask.ca>
Sent: Saturday, September 12, 2009 12:20 PM
Subject: gum negatives redux

> Hi all...
> I'm getting much better results using my QTR inkjet palladium
negatives for
> pure gum purposes. Detail is much sharper with these contrasty
negs and I'm
> getting a pretty full range of tones.
> Exposures with 1:1 gum/dichromate ratio (pot di) are 6-7 min for
> 2 1/2 min for shadows and mids somewhere btw those.
> This is for exposure in full blazing blue sky sun, Southern
> style.
> Still adjusting and experimenting, but happy to have a printing
day that is
> not frustrating ;-)...of course, it's not over yet.
> Paul