PDA

View Full Version : Red Sensitive Dye ?



Pages : [1] 2 3 4 5

wildbillbugman
06-19-2013, 12:46 PM
Hello PE and Everybody else,
I wonder if anyone out there has had any success sensitizing an emulsion to Red. Sand's SDA3057 works very well to this purpose. But at $600/gram plus a Convenience Fee it is just cost prohibitive. A while back PE wrote of one of his connections possibly producing some dyes for Emulsion Makers. I wonder, is this still possible.
If I have no alternative, I will buy more of the SDA3057. For my work, nothing but panchromatic emulsions will do. I have been evaluating some dyes. But none do as well as "J Agrigated" SDA3057.
Believe it or not, chlorophyll, freshly extracted from spinach, shows some red sensitivity, but nothing like SDA3057.
Just Dreaming,

kb3lms
06-20-2013, 12:26 AM
Hi Bill,

In some very old literature, I have read about "Brilliant Green" and "Malachite Green" giving some red sensitization. I doubt it's what you are after tough. Brilliant Green is cheap, though, and I have a bit coming in to try out. It's used in Russia like Mercurochrome as an antiseptic. You can get it through eBay.

I have just tried using chlorophyll but with no effect at all. When do you add the chlorophyll and how much? Maybe I did not do it right.

I've also tried erythrosine for green but added just before coating which did not do much of anything. Next time I will try during precipitation like PE says to do.

-- Jason

falotico
06-20-2013, 02:26 AM
Erythrosine was used by du Hauron in 1878 to produce the first color photographic print using cyan, magenta and yellow. This dye barely sensitized the emulsion to red light--mostly it sensitized it to green. Consequently the exposure through the green filter was for twenty seconds or so, but the exposure through the red filter (actually orange) was for as long as three minutes.

A discussion of ways to sensitize emulsions can be found in a book which is available for free online, E.J. Wall's "The History of Three Color Photography" (1925), here:

http://archive.org/details/historyofthreeco00ejwa

Read his chapter on "Color-sensitive Gelatin Plates". He discusses two good candidates: ethyl violet; and pinacyanol blue. Ethyl violet, IIRC, was the sensitiser used in Autochrome screen plates. It produced passable reds although not as sensitive to deep red colors as more modern emulsions. Ethyl violet is available from Sigma-Aldrich, 25 grams for $39.90.

The other likely candidate is pinacyanol blue, aka pinacyanol chloride. This is available also from Sigma-Aldrich, a quarter of a gram for $20.20. Besides Wall, see US patent 2047022. There are other dyes, consider cyanine. I understand that Malachite Green tends to fog film, but Wall does mention it in one recipe.

kb3lms
06-20-2013, 11:40 AM
There are so many mentioned by the likes of Eder, and probably many more today than were available in his time. The cyanines are the best, as we know, but they are also expensive. Some of these other cheaper dyes are interesting to try, though, as alternatives. But who would have time to try them all!

wildbillbugman
06-20-2013, 01:37 PM
Thanks for more response than I dared to hope for! I Think I might already have some of the dyes mentioned. I will be doing some tests soon.
I requested a new quote for SDA3057. They keep making it more expensive.
For chlorophyll, I always start with packages of baby spinach leaves from the suoermarket. I have been using 92% Isopropyl alcohol. I add the chlorophyll at 200-ng per mole of AgNO3
It may be better to add befor preipitation. Also IPA may not be the best solvent
Bill.
Bill

Kirk Keyes
06-22-2013, 09:50 AM
Bill, we use acetone as a solvent for chlorophyll analysis at work.

wildbillbugman
06-22-2013, 01:16 PM
Hi Kirk,
I am glad to hear from you! There are at least 6 different "kinds" of chlorophyll, A through F. Different solvents may extract different types, or worse, alter different types. Someone suggested that Heptane would extract Chlorophyll B from a more hodge podged mixture. Yes, "hodge podged" is a recognized Scientific term.
We are still waiting for you to make a T-grain emulsion.
Bill

Kirk Keyes
06-23-2013, 03:01 AM
We'll need to wait a bitmore for my next emulsion. But my daughter was quite excited by all the little praying manti that hatched from the eggs we bought last week! She wanted to keep several as pets, but I talked her into letting them go into the garden. I secretly named them all "Lenny"....

wildbillbugman
06-23-2013, 11:56 AM
Kirk,
You made the right choice by not keeping these mantids. Not all species are suited to be pets. Those species from arid areas are aggressive because they need to be. Those species, like Lenny, from forested areas can just let their meals come to then. These are the gentle mantids who do not mind being handled.

Kirk Keyes
06-23-2013, 10:16 PM
Thanks for that info, Bill. I had been thinking about getting one as a pet. I'll do some research in species first though!

"The Gentle Mantids" - that would be a good name for a band!

wildbillbugman
06-23-2013, 11:20 PM
Kirk,
I forgot to say, you never want to be bitten by a mantid! The pain is far worse than any bee sting. And the little twerps do not wanna let go.

holmburgers
06-25-2013, 06:26 PM
Howdy gents,

Ron informed me that there was a thread about trying to find some red sensitizing dyes. Although I've not started messing around with any color sensitizing dyes myself yet, I do come across a lot of information regarding it. Attached is an excellent list of sensitizers from Hans Bjelkhagen's Silver Halide Recording Materials: For Holography and Their Processing. I'd consider this list an authoritative survey of the currently available sensitizing dyes.

Unfortunately it doesn't say which spectral region they sensitize for, but this information has been hashed out ad nauseum in historic literature. I was recently amazed at how many articles I found in British Journals of Photography, 1900-1918, that discuss red sensitization and the like. Has anyone considered bath sensitization?

Here's an interesting snippet from Bjelkhagen's book... "The particular sensitizing dyes mentioned above [below] and their combinations were discovered and used by H. Lehmann to produce the best correct-color sensitivity ever achieved in Lippmann photography. However, he kept secret his good formula for Lippmann plates and it was not revealed until after his death. If one wants to try this old photographic technique today, these dyes are definitely the first choice."

Those dyes are:
Pinacyanol ----- 1:1000 [chloride, I presume]
Orthochrom T -- 1:1000
Acridine orange - 1:500

I think this would be an excellent trio to work with as an amateur emulsion maker.

Best wishes y'all!

Kirk Keyes
06-26-2013, 01:38 AM
There's a book on IR film from the 1950s that has a similar list, by Clark, I think. It has a good discussion on the history of sensitizing dyes,with a slant towards the cyanine dyes and IR.

wildbillbugman
06-26-2013, 01:19 PM
Hi all,
I have the Bjelkhagen book and have tried to obtain some of the dyes with a lot of frustration. I have seen Bjelkhagen's work with super resolution printed holographs. They are amazing. Images that can be printed in a book, but 3D, high color saturation , resolution and contrast. Dare I use the word 'magical'?
I would recommend this book to anyone interested in holography. Dye sensitization is only one early chapter.

VesaL
08-21-2013, 12:51 PM
Hello!

Is it possible to substitute ethyl violet to Methyl violet?
Thank you for your help.

Regards,
Vesa

falotico
08-21-2013, 07:28 PM
There are recipes for methyl violet, (aka crystal violet), as a red sensitizer, cf. p. 255, Wall, "History of Three Color Photography," available online at:

http://archive.org/details/historyofthreeco00ejwa

Reading all of chapter VII is very informative about sensitizing emulsions. Methyl Violet has an absorbance spectrum very close to ethyl violet and chemically the two dyes only vary by substituting methyl groups for ethyl groups.

Tom1956
08-21-2013, 10:01 PM
Hello PE and Everybody else,
I wonder if anyone out there has had any success sensitizing an emulsion to Red. Sand's SDA3057 works very well to this purpose. But at $600/gram plus a Convenience Fee it is just cost prohibitive. A while back PE wrote of one of his connections possibly producing some dyes for Emulsion Makers. I wonder, is this still possible.
If I have no alternative, I will buy more of the SDA3057. For my work, nothing but panchromatic emulsions will do. I have been evaluating some dyes. But none do as well as "J Agrigated" SDA3057.
Believe it or not, chlorophyll, freshly extracted from spinach, shows some red sensitivity, but nothing like SDA3057.
Just Dreaming,

What in the heck kind of ANYTHING on this earth could cost $16,800 an ounce? That doesn't make sense. What good could it have possibly have been even to a company like Kodak was in film manufacture at a crazy price like that. Surely there is another reasonable alternative to making film panchro.

MattKing
08-21-2013, 10:23 PM
What in the heck kind of ANYTHING on this earth could cost $16,800 an ounce? That doesn't make sense. What good could it have possibly have been even to a company like Kodak was in film manufacture at a crazy price like that. Surely there is another reasonable alternative to making film panchro.

$16,800 an ounce would be cheap if a single ounce is/was enough to sensitize an entire run of a particular film.

Probably work out to much less than a penny a roll.

VesaL
08-22-2013, 02:23 AM
There are recipes for methyl violet, (aka crystal violet), as a red sensitizer, cf. p. 255, Wall, "History of Three Color Photography," available online at:

http://archive.org/details/historyofthreeco00ejwa

Reading all of chapter VII is very informative about sensitizing emulsions. Methyl Violet has an absorbance spectrum very close to ethyl violet and chemically the two dyes only vary by substituting methyl groups for ethyl groups.



Thank you very much for your kind help Falotico. I will try Methyl violet with suggested 50% alcohol. Now how to mix 1:20 000 is an another feat... :0)

-Vesa

falotico
08-22-2013, 02:57 AM
There are some drug stores which sell an alcoholic solution of crystal violet (aka methyl violet) using the name "Gentian Violet." These come in small bottles, about one half ounce, and are sometimes mixed with 10 percent alcohol. They are already measured into a concentration of one percent or two percent, that is 1 to 100 or 2 to 100. A half ml of the one percent solution in a liter of water/alcohol would reach a concentration of about 1:20,000. Simply observing the shade of that concentration would give you a reasonably accurate idea of what 1:20,000 looks like and you could try to match it using an eye dropper. The risk in these dyes is using too much. Interested to see how it works out--good luck!