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wildbillbugman
09-01-2008, 06:41 PM
Hello,
After about 1 year of planning, thinking,purchasing equipment for working in total darkness and purchasing chemical,as well as becoming practiced in blue sensative emulsion making, I am about to actualy attempt to make a panchromatic silver-gelatin emulsion.
My first attempt will be to make Jim Browning's Matrix Emulsion and apply the suggestions that Ron made on 7/28/07 on this Forum to this end.
My purpose in starting this Thread is to inquire if anyone here has attempted to make a homemade Pan emulsion. I would like to read about your experiences. Mabe someone has already posted about such activities within this forum and I just have not found those posts.
I would welcome any post describing your attempts, succesful or not.
I will be posting my own results on this Thread.
Regards,
Bill

Kirk Keyes
09-02-2008, 12:41 AM
Bill, I've not tried yet. What dye are you going to use??

Kirk

PS - how did your hand surgury go?

wildbillbugman
09-02-2008, 12:24 PM
Hi Kirk,
Back about a yeae ago, Ron poasted his ideas about how Jim Brownings Dye Matrix emulsion could be converted to an in-camera pan emulsion. He recommended two specific dyes and those are what I will use. $150/GRAM + Conveniance Charge=$375!. You can search out Jim's recipe and Ron's suggested changes on this Forum.
I am having my stitches out today.IHOPE TO BE WORKING ON EMULSIONS IN A FEW DAYS.
Regards,
Bill

Photo Engineer
09-02-2008, 01:48 PM
Bill;

Before spectrally sensitzing the emulsion, please check it out beforehand with only blue sensitivity to insure that it has the desired speed, fog and contrast. Then do the dye work.

Also, remember that good green sensitization will give a reddish colored emulsion and a good red sensitization will give a greenish colored emulsion.

PE

dyetransfer
09-02-2008, 02:06 PM
Hi Bill, You may want to add a gold chloride sensitizer as well as the hypo addition. You will want to sample the emulsion at various times during the sensitization - at Fotokemika they coated glass plates, and exposed them without drying. They would expose and develop, and look for fogging or a change in the color of a step wedge image. They didn't fix the plates, just examined it in room light for a few seconds. You will probably get a bit more fogging with the gold sensitization, but at least a stop greater speed. REgards - Jim Browning

Kirk Keyes
09-02-2008, 02:43 PM
Bill - that sounds great! I'm glad the hand is coming along.

Would you be willing to sell a couple dozen milligrams of your dye?

Ray Rogers
09-02-2008, 02:43 PM
...they coated glass plates, and exposed them without drying. They would expose and develop, and look for fogging or a change in the color of a step wedge image. They didn't fix the plates, just examined it in room light for a few seconds.


Hi Jim,

You watched then do this?
How long diid it take between coating and judgment?
After this sort of test, what were their possible moves?

Ray

Ray Rogers
09-02-2008, 02:46 PM
Would you be willing to sell a couple dozen milligrams of your dye?

To others?

Photo Engineer
09-02-2008, 03:34 PM
Ray;

We did something similar at Kodak. You test samples for the maximum amount of sulfur + gold and the maximum time and the maximum temperature. It is an emulsion factor we call EOF or Extent Of Finish and is measured in KCal / mole of silver. So our method, while similar is quantized.

PE

wildbillbugman
09-02-2008, 04:45 PM
Yes Ron and Jim,
I will certainly test the emulsion befor spectral sensitzation. And at every step durring the entire process.And I will try a gold chloride sensitizer(Stiegmann's?), after I haved looked at it without one.
Making the Big asumption that other things go well, do you reccomend glyoxal as a hardiner? I don't intend to harden anything until I have my other ducks in a row?
Also, I will work in smaller batches than Jim's formula calls for. My first batch will be for 1 liter,total .
Thanks,
Bill

Photo Engineer
09-02-2008, 05:16 PM
For film, glyoxal or chrome alum or both in a mixture, but for plates only chrome alum is suggested.

Be careful of chrome alum with some sensitizing dyes. It will harden faster with some dyes due to an interaction of some sort. I have had one small batch with chrome alum set up on me during the coating session.

PE

Ray Rogers
09-02-2008, 06:22 PM
Ray;

We did something similar at Kodak. You test samples for the maximum amount of sulfur + gold and the maximum time and the maximum temperature. It is an emulsion factor we call EOF or Extent Of Finish and is measured in KCal / mole of silver. So our method, while similar is quantized.

PE

???

What did you measure?
The actual incorporation of S+Au vs. time and temperature?
While My Chemistry Gently Sleeps, I must ask, do you actually measure KCal or just calculate it?

How we get KCal out of density data?

Are you talking about the standard enthalpy of formation or (standard heat of formation) and if so which compound?

???
Ray

Photo Engineer
09-02-2008, 06:36 PM
You run a series at different levels of S/Au, temperature and time. The measurements are speed and fog. From the optimum time and temperature, you can derive Kilo Calories input / mole of silver. If you then vary the temp/time or rise and fall profile, but keep KCal / mole constant, the finish should give about the same result but with slightly altered properties. I don't intend to go into detail any more than this. It is one of the little factors that those who say they "know a lot about emulsions" never seem to get around mentioning.

Just as we had models to work with making and scaling emulsions, we had a computer program which did all of this for us. Unfortunately, I am reduced to doing this all by trial and error, and at great cost in time and silver nitrate. :(

PE

Ray Rogers
09-02-2008, 07:25 PM
...you can derive...input / mole of silver.PE

Thanks Ron.

I use a different parameter than KCal (plus several not mentioned) but I know what you are talking about.

Ray

Ray Rogers
09-02-2008, 07:29 PM
Just as we had models to work with making and scaling emulsions, we had a computer program which did all of this for us. Unfortunately, I am reduced to doing this all by trial and error, and at great cost in time and silver nitrate. :(

PE

Are you bragging or complaining?!!

The fact that you had the people and equipment to help you model, predict and compute must have made you lazy!:D

Ray

Photo Engineer
09-02-2008, 07:39 PM
Are you bragging or complaining?!!

The fact that you had the people and equipment to help you model, predict and compute must have made you lazy!:D

Ray

Au contraire, I wrote a good portion of the modeling program so it was hard work all the way.

PE

Ray Rogers
09-02-2008, 08:04 PM
I don't intend to go into detail any more than this. It is one of the little factors that those who say they "know a lot about emulsions" never seem to get around mentioning.PE

Who do you mean by that remark? !

Honestly, I wish people would stop gving him a hard time.

Why DO you keep picking on the poor guy?

You might not know this, but Ron (aka "PE") DOES know a lot about emulsions!
So back off and give him a break!

Golly Gee Willikers!:D

Photo Engineer
09-02-2008, 08:58 PM
Golly Ned Ray! My aqueous humor is tearing me apart. :D (pun there for those that get it)

No one has given me a hard time Ray. They just avoid the topic and allude to their "vast knowledge" when it is really "half vast". 'Nother pun. Finish has been largely ignored in the posts here, and rightly so as it is arcane and was really outside of my main area of expertise. I was writing finish model programs when I retired and it kept going after I left. I can do them, and know what is going on, but I don't know the details of the more complex varieties used in some cases.

PE

Ray Rogers
09-02-2008, 09:39 PM
"half vast"
PE

Nice one and appropriate, too!

Well, it has been fun!
But now I have to do something productive!

(like DREAMING)

;)
Ray

Photo Engineer
09-02-2008, 09:45 PM
Ray;

Since it is bright afternoon where you are and dark night in Rochester, you are way out of synch. I guess you missed the other pun.

PE