Red Sensitive Dye ?

[Tom1956]

The reason I'm following this thread is a hairbrain idea of wondering if you could simply soak sheets of green X-Ray film in a solution of this violet stuff and raise the sensitivity closer into the red end of the spectrum. If anybody wants to comment on this knucklehead idea, I'll read it gratefully.

 

[falotico]

Wow, X-ray film! My recollection is that X-ray film contains chemicals which will fluoresce when irradiated with x-rays. The x-ray exposure causes fluorescence and the silver halide grains are sensitive to the visible light which is produced in this manner. I hazard a guess that the visible light is green/blue in color, so the x-ray film is probably sensitized to green/blue. Sensitizing dyes tend to be ionically attached to the silver halide grains so they should be removed in order to make room for the red sensitizing dye. You might mix the red dye sensitizing solution with ammonia which might dissolve some of the built-in dyes; it will certainly dissolve the small percentage of silver chloride grains since silver chloride is soluble in ammonia. Also ammonia might soften the gelatin which has probably been hardened--a softer gelatin will encourage the up take of the red sensitizing dye. Hydrogen peroxide will also soften hardened gelatin. All this is fairly convenient chemistry.

 

[Tom1956]

Well I figured it couldn't be that easy. It PE even saw read that hairbrained post of mine, he's probably rolling his eyes and possibly rolling on the floor laughing. I'll exit the thread and let all it to return to the better minds like the OP had sought.

 

[dwross]

Did anyone see and note holmburger's suggestion? Post #12. It was very sound. Pinacyanol chloride, together with erythrosin b, makes a perfect (and I mean that pretty much literally) panchromatic emulsion.

d

 

[kb3lms]

My recollection is that X-ray film contains chemicals which will fluoresce when irradiated with x-rays.

Not exactly. The film is either just blue sensitive or orthochromatic. When used it is sandwiched in a cassette (flat film holder that opens like a book) between two phosphor coated plastic sheets, called screens, that fluoresce when struck by x-rays. In many ways it is a fairly conventional film although the spectral response is tuned to the spectral emission of the screens for maximum sensitivity. It is also coated on both sides, no anti halation and often on a blue colored base. Whether the dye trick would work or not I do not know but there is nothing really different about the film. Large format photographers use it sometimes because it is cheaper as it is still made in considerable quantity - compared to sheet films.

 

[Photo Engineer]

Guys, X-Ray film is placed in contact with a screen the fluoresces when struck by X-Rays. Nuclear emulsions, sensitive to radiation, contain a substance to enhance their sensitivity to specific radiation. See Mees or Mees and James for this.

Chlorophyll is used by Mark Osterman at GEH. He uses Ivy, and extracts the dye getting a greenish solution. It does not keep its properties long.

Chris' list should serve us well, as should his suggestion.

I have not been able to get any information from my contacts, but some of the chemicals Chris suggests are available commercially.

There, that should answer most questions.

PE

 

[Hexavalent]

Pinacyanol has been discussed at great length over the past few years. AFAIK, the variability in aggregation, and a tendency to floculate can make it a bit tricky for controllable and repeatable results within the "home lab".

 

[Tom1956]

Guys, X-Ray film is placed in contact with a screen the fluoresces when struck by X-Rays. Nuclear emulsions, sensitive to radiation, contain a substance to enhance their sensitivity to specific radiation. See Mees or Mees and James for this.

Chlorophyll is used by Mark Osterman at GEH. He uses Ivy, and extracts the dye getting a greenish solution. It does not keep its properties long.

Chris' list should serve us well, as should his suggestion.

I have not been able to get any information from my contacts, but some of the chemicals Chris suggests are available commercially.

There, that should answer most questions.

PE

Did it answer MY question too, because if it did, I'm sure I'm not versed enough to notice.

 

[Photo Engineer]

IDK. Restate the question!

PE

 

[Tom1956]

Post 26 and 28:
08-22-13 04:47 PM (there was a url link here which no longer exists)
(there was a url link here which no longer exists)

Join DateMay 2013LocationUSShooterLarge FormatPosts626

The reason I'm following this thread is a hairbrain idea of wondering if you could simply soak sheets of green X-Ray film in a solution of this violet stuff and raise the sensitivity closer into the red end of the spectrum. If anybody wants to comment on this knucklehead idea, I'll read it gratefully.​

 

[dwross]

Pinacyanol has been discussed at great length over the past few years. AFAIK, the variability in aggregation, and a tendency to floculate can make it a bit tricky for controllable and repeatable results within the "home lab".

I think I see the crux of the problem for this forum. (At least I see it as a problem.) "...has been discussed at great length..." Yes, much discussion of everything under the sun. Much less doing. And, far too many conclusions drawn from the discussions -- with little empirical evidence to back up said conclusions. I'm a retired scientist. I'm not much given by nature or training to act that way. I've got a number of lovely handmade panchromatic film negatives and glass dry plates on my light table.

d

 

[Photo Engineer]

Post 26 and 28:
08-22-13 04:47 PM (there was a url link here which no longer exists)
(there was a url link here which no longer exists)

Join DateMay 2013LocationUSShooterLarge FormatPosts626

The reason I'm following this thread is a hairbrain idea of wondering if you could simply soak sheets of green X-Ray film in a solution of this violet stuff and raise the sensitivity closer into the red end of the spectrum. If anybody wants to comment on this knucklehead idea, I'll read it gratefully.​

Thanks.

Yes, it can probably be done but most sensitizing dyes are also desensitizers and so getting the correct amount is difficult. And proving it works is another matter.

PE

 

[Photo Engineer]

I think I see the crux of the problem for this forum. (At least I see it as a problem.) "...has been discussed at great length..." Yes, much discussion of everything under the sun. Much less doing. And, far too many conclusions drawn from the discussions -- with little empirical evidence to back up said conclusions. I'm a retired scientist. I'm not much given by nature or training to act that way. I've got a number of lovely handmade panchromatic film negatives and glass dry plates on my light table.

d

Denise, I agree. However, I must ask if you have wedge spectrograms of your pan emulsions showing good red sensitivity? This would be hard scientific evidence that it works. If you don't, I would be happy to expose a few of your plates for you and return them to you for processing, as I have a Spectro Sensitometer. That is the ultimate proof.

PE

 

[dwross]

Thank you. That's a generous offer. I know how valuable your time is.

Actually, I disagree with that approach for us at this time and place in the history of our craft. I think it is a fundamental mistake to consider our efforts a de facto competition with standards based on the latest modern materials that come from a Kodak factory. That's the exact rabbit hole the discussions here so often travel down.

Today, my hat says 'artist'. I believe good art more often comes from good practices more than from dumb luck, but it is still art. An artist makes the materials his or her own according to personal vision. In other words, the "proof" is in the product (i.e. the art), not a number on a machine. Arbitrary, spurious precision may be seductive, but mostly it's an excuse to procrastinate making good art.

d

 

[Photo Engineer]

Denise, I was going by your previous post suggesting that we all get more evidence of our conclusions. This test would compare nothing to nothing in the sense that your plates would be for you alone (even I would not see the results!) and thus you would have that concrete evidence of pan sensitization rather than a guesstimate.

Any time, I am available for helping you just as I spend time with others here either designing processing solutions or making emulsions.

Ron

 

[dwross]

Well, dichotomous philosophical camps it is. I feel like I'm talking to a brick wall. I have to imagine you feel the same way. Viva la. Hopefully our two camps are yin and yang and not pushmepullyou!
,
d

 

[VesaL]

Still waiting the mailman to deliver the methyl violet and and milligram/gram scale, i have not yet been unable to try the sensitizition. Wondering how long you will have to keep the plates in chilled alcohol bath.. Well, one plate and exposure/processing at the time

 

[Andrew O'Neill]

Any results, VesaL?

 

[wildbillbugman]

"Crusader Rabbit" Reporting back to duty! Has everyone forgotten about Sand's SDA3057? This stuff, suggested by PE about 5 years ago, really works. Pricy at about $400/gram after Convenience Fee and taxes. But TIME is money too. After spending some time with 2 cheaper red sensitive dyes, I am giving serious consideration to just suspending my search for a cheaper red sensitive dye and biting the bullet for $400.
I am not getting younger and my research needs to be showing some images, not just talk.
I have just finished taking a class in Layered glass fusing. I am gonna stop gluing my layers together and start fusing them together. This will require a reliable panchro emulsion.
I will report more as I progress. But, for full color images I will need to abandon water color pigments in favor of fineable Frit. I intend to load a panchro emulsion with Cyan, magenta or yellow Frit. For those who are not familiar with Warm Glass Working, Frit is pigment dispersed in glass and ground. It is usually used in free hand art on glass, or screen printed on glass. But I intend to photo image it onto glass before firing it in 4-16 layers. I will be using Pt/Pd/Au for the grayscale portions of this work.
Who would ever consider placing a piece of art on paper anyway? Paper belongs to the trees!
Bill

 

[Photo Engineer]

Keep that Sands dye alive guys.

Here is the big secret! It is the red sensitizer for KODACHROME! It is one of the few dyes that can survive development and still be active. So, someday, if there is a researcher who wants to recreate Kodachrome, this is the dye to use.

PE

 

[kb3lms]

It is the red sensitizer for KODACHROME!

I was wondering if that wasn't the case. Not necessarily Kodachrome but one of the available films. On a related note, I have obtained a bit of 2718 from "THE LIST." Looking forward to trying it out.

Jason

 

[wildbillbugman]

Hello PE,
I am still a bit confused about what appears to me to be a contradiction between your original recommendation of 200mg SDA3057 per mole of Ag and a latter statement that the dye should be used at 60 mg per mole of Ag. Because of J aggregations, the dye needs to be double coated over the particles of silver halide. Without the j aggregation, SDA3057 is just another green sensitive dye.

 

[Photo Engineer]

Bill;

In practice, you must determine the best level of dye by trial and error. I always do a concentration series.

And, the amount varies from emulsion to emulsion and of course if you want J aggregation it takes 2x the amount, however if aggregation is going to take place it will and may only cover 1/2 of the emulsion. Therefore it is best in this case to optimize for the aggregate to form rather than some sort of mix.

PE

 

[wildbillbugman]

OK, Here I go again. Hexavalent and I are gonna get together on a gram of SDA3057. I will only ask once. Is anyone else interested?
PE- I have been using SDE3008 as a green sensitive dye, in conjunction with the SDA3057. BUT(!) Making two different emulsions, one with 3057, the other with 3008, I have seen evidence of j aggregation with the 3008. The emulsion turns lavender, like with 3057. But it takes standing overnight for this color shift to happen,

 

[Photo Engineer]

Bill, sensitize and then coat. Once dry it should be ok.

There are a number of solutions to this. I have not observed the 3009 aggregating, but then I sensitize and coat.

PE