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wildbillbugman
09-02-2008, 11:00 PM
" Finish has been largely ignored in the posts here, and rightly so as it is arcane "

PE[/QUOTE]

Ron, Is not mixing emulsions on a bench, like some of us are doing, "arcane"?
I thought that keeping alive these "arcane" practices is the whole point of your Wokshops,The Light Farm. and this very Forum. If not, lets all just purchace digital camers, the latest Photoshop and "To Hell with It"!
Just for the record: I for one have never said that I had any knowledge of Emulsion making, other than what I learned from you and a few others. All I said is that I was "practiced" and "Pracice" includes a bunch of failed attempts.
Joy anf Cheerio to All,
Bill

Ray Rogers
09-02-2008, 11:14 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

About watery eyes??

or the finish program that didn't.?

Well it is true about the sun outside.
But I live in a dark room. For me the safelight never sets.

Ray

Ray Rogers
09-02-2008, 11:36 PM
" Finish has been largely ignored in the posts here, and rightly so as it is arcane "

PE

Just for the record: I for one have never said that I had any knowledge of Emulsion making, other than what I learned from you and a few others. All I said is that I was "practiced" and "Pracice" includes a bunch of failed attempts.
Joy anf Cheerio to All,
Bill[/QUOTE]

---------------------------------------------
Whoa, there now Wildbill,

I feel a might responsable for this, uh confusion.
I could be always be wrong, but I surely think PE had other people in mind when he wrote that. Without a doubt!

Although it is not my place to say so, please don't take it personally, as it definately was not directed at you.

While PE did use the term arcane, he is just commenting on the fact that this method began a long time ago and things have become more automated.

I don't like it when someone "ages" my emulsions by saying the technology is decades old, and arcane does seem rather servere, but no one had you in mind when those sentences were downed.

Best Wishes

Ray

Kirk Keyes
09-03-2008, 12:12 AM
Bill - I'm curious about how you were going to test the spectral senstivity of your emulsion. What kind of test are you going to do?

Also, when you get this to work, you need to get a peristaltic pump so you can do some double runs and make a T-grain film. :^)

wildbillbugman
09-03-2008, 12:42 AM
Hi Kirk,
I might consider selling a few dozen mg of the spectral dyes to you,as you are a fellow insect fan. As of yet, I have not opened the vials they came in. They are tucked in a dark corner of a freezer.
As for testing the spectral sensitivity of my future emulsions, I intend to place a Kodak color chart transparency over the emulsion,which has been coated on glass, and expose with pops of a strobe. Thats as close to white light as I can get, ouside of going outside.
As fof your T-grain emulsions, I thought that was your baby! I am waiting for your initiative.

wildbillbugman
09-03-2008, 12:48 AM
Ray,
Thanks. Mabe I'm just overly sensative. I am painfuly aware that my carcase cannot keep up with my ambitions.
Let us forget it,
Bill

Ray Rogers
09-03-2008, 03:18 AM
(Bill, just between you and me, I think Ron was actually talking about me!:()

Photo Engineer
09-03-2008, 09:54 AM
My comments were meant for no one here on this thread at all. Sorry for the misunderstanding. I apologize for any confusion.

As for testing Bill, I suggest using a WR 98, 99 and 70 (or equivalent narrow cutting filter set) over a step chart and exposing. An in-camera exposure is difficult to read, but a 3 color filter set with and without dye will give you the exact speed change in each region affected in terms of Log E (stops) speed change.

I've tried the method you describe, Bill, and it is just not clear cut enough. However, if you wish to send me a sample, I'll expose it with my spectrosensitometer.

PE

wildbillbugman
09-03-2008, 12:40 PM
Thanks Ron,
I will follow your suggestion concerning exposing through WR filters. Sound a bit easier anyway.
Bill

Kirk Keyes
09-03-2008, 12:52 PM
Bill - you should take Ron up on the spectrosensitizer. I've seen test prints from it and it is really cool and gives results just like you seen in the graphs in books and such.

Photo Engineer
09-03-2008, 02:23 PM
[QUOTE=wildbillbugman;675714
Ron, Is not mixing emulsions on a bench, like some of us are doing, "arcane"?
I thought that keeping alive these "arcane" practices is the whole point of your Wokshops,The Light Farm. and this very Forum. If not, lets all just purchace digital camers, the latest Photoshop and "To Hell with It"!
Just for the record: I for one have never said that I had any knowledge of Emulsion making, other than what I learned from you and a few others. All I said is that I was "practiced" and "Pracice" includes a bunch of failed attempts.
Joy anf Cheerio to All,
Bill[/QUOTE]

Bill;

I forgot to reply to this.

I am trying to make emulsion making as fool proof and "un-arcane" as possible in my formulas. I hope you saw that in the emulsions we made. They are just about dump and stir.

I'm trying to make the advanced emulsions easy as well, but they will cost more in terms of equipment though.

I have not addressed finishing yet, I've merely used a standard condition more or less worked out by trial and error here at home with the bench top emulsions.

I was not pointing a finger at anyone here in this thread, nor intending anything bad about anyones work. Sometimes though I feel like a person who has started a huge rock rolling downhill. I have to step back to get out of the way. Other times, people point at me and say "its all his fault and he doesn't know what he is doing" as the rock goes bounding down hill. :D

So, that is all there was to my comment. I feel as if I want to be there to help!

Now for finishing, you are using thiocyanate + gold. Here is the order of use timewise from early days to modern:

Active gelatins > Allyl Thiourea > Thiourea > Thiocyanate > Sodium Thiosulfate

Gold was used after about 1945 at Kodak with all of the above, but hypo was used exclusively for Sulfur sensitization since the 50s or 60s. Of course there is Reduction Sensitization (R type) which uses Stannous Chloride and a whole variety of other methods. Hypo seems to be the compound of choice for sulfur + gold though, but the hypo must be freshly mixed.

Hypo and the others above put Silver Sulfide specks on the grain, but Stannous Chloride forms Silver metal specks on the grain.

Other methods include addition of strong alkali, strong acid and a host of other methods to form a speck on the grain to "jump start" latent image formation.

PE

dyetransfer
09-03-2008, 05:00 PM
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

Hi Ray - I did watch them do this. Every 10 minutes or so, they would coat a glass plate with emulsion, expose it with a projection system. and develop (but not fix it). They would bring the plate into the emulsion chemist's office in a box and she would evaluate it quickly after removing the lid in full office light. She whould inspect it for fogging, and color change. Of course, since it wasn't fixed out, she had to work quickly. I'm not sure how long the process took to do, but the important thing was the record of samples 10 minutes apart which were done as the emulsion was sensitizing. Take a look at the attached file.

Regards - Jim Browning

dyetransfer
09-03-2008, 05:03 PM
Hi Bill - I use glyoxal now as a substitute for formalin in my hardner. I use the same concentration, and it works well. This is the hardner I use on the matrix after it has been washed off. This makes for a much more durable matrix. Not sure how it would work in an emulsion though, that is a much more complex thing.

Regards - Jim

Ray Rogers
09-03-2008, 06:51 PM
Hi Ray - I'm not sure how long the process took to do....

Regards - Jim Browning

Jim, what size plate are we looking at?

I was wondering about
how long and completely
the emulsion was allowed to set.

Interesting chart- do you have a close up of it, or know where its from?

Ray

Photo Engineer
09-03-2008, 06:51 PM
The method of using the glass plate that Jim describes above is limited in some cases such as our lab bench scale emulsions. A plate coating for a 4x5 takes about 6 ml of emulsion and over a 60 minute finish will therefore require about 36 ml of emulsion from a 200 ml batch as one example. That is a lot to use before you even start. To add to this, often we are making slow speed emulsions that cannot be easily printed by projection. Some print film and paper emulsions could not be tested this way due to speed and volume being made.

Just some thoughts. It is useful but there is a better way.

PE

Ray Rogers
09-03-2008, 08:02 PM
"...people point at me and say "its all his fault... he doesn't know what he is doing"

I must say that I have seen both sides of the story.
I see a lot of misunderstanding mixed in with a lot of ego conflict / ego injury.

Alas, we are but human!

Thives of another animal's breast milk!

Ray Rogers

dyetransfer
09-03-2008, 11:47 PM
Hi Ray - the plate size was 4 x 5". Not sure how long it took the gel to set or if the plate was chilled, but I imagine that it was. Obviously, you want to develop the image as soon as possible after coating it so the emulsion doesn't continue to evolve. The chart was a glass plate (I think) that was placed in a very old looking projector - black wrinkle finish. But the projector looked to be very well made and the projected image was sharp. I don't know what they developed the plate in, but I doubt it was pyro.

Regards - Jim

Ray Rogers
09-04-2008, 12:50 AM
Hi Ray - the plate size was 4 x 5". Regards - Jim

OK,

Thanks Jim.

Kirk Keyes
09-04-2008, 12:09 PM
The method of using the glass plate that Jim describes above is limited in some cases such as our lab bench scale emulsions. A plate coating for a 4x5 takes about 6 ml of emulsion and over a 60 minute finish will therefore require about 36 ml of emulsion from a 200 ml batch as one example.

Ron - You may have missed it, but Bill said he was going to make 1L of emulsion, so he should have plenty to test with. But for much smaller batched, this method would cut in quite a bit to the final volume.

Kirk Keyes
09-04-2008, 12:11 PM
The method of using the glass plate ...
Just some thoughts. It is useful but there is a better way.

OK - did I miss the description of the better way? Or have I just forgotten it?

Kirk