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Photo Engineer
02-13-2011, 03:07 PM
At our recent GEH workshop, someone passed out a table containing formulas for 5 grades of Brovira paper which were taken from Glafkides. I tried looking at Glafkides, but there is not a copy to be had locally as far as I can determine. I looked in Duffin, and he quotes Glafkides on two formulas and states that all of the data in Glafkides and also Duffin regarding emulsion formulas in that chapter come from the FIAT and BIOS reports on Agfa and other German manufacturers at the end of the war.

Well, someone helped me out and I read all of these formulas in the original FIAT and BIOS reports and have made some interesting findings.

1. Step #9, reported in the table I have, is wrong. One entire ingredient is omitted, and the values for the others quantities are offset downwards by one therefore making this entire portion incorrect.

2. The original formulas specify the exact type of gelatin at each step, ie. Hard, Medium, Weak and etc, referring to the amount of Sulfur ripening provided by the gelatin. This would have to translate into a modern Sulfur sensitizing step if one were to make any of them today.

3. Times of addition are specified in most cases, but the table purportedly from Glafkides omits it all.

And, most stunning, in the original reports, the English interpreter runs the German SZ together turning it into a B in English, and creates 2 words. Now, either way this can be still read properly but it depends on whether you are a cook or a chemist.

In cooking, it translates as "to begin cooking dump over" or "baste with sauce" but to an emulsion maker it means "to make a coating use this to prepare properly". It implies dump into or coat over though. This may be critical.

Since there are 7 ingredients, including gelatin which was omitted in the table, it is vague as to whether these are finals to be added before coating or to be coated as an overcoat. Since a group of "finals" are added earlier in the formula, this could be an overcoat, but I doubt it. I have discussed this with a native German speaker who is an emulsion maker, and he too is in doubts, but we both feel it could go either way. We lean towards additional finals but without proof.

I peeked at other Brovira formulas (there are 10 in all) and Portriga as well. These latter contain sensitizing dyes and stabilizers to protect the paper during keeping.

This is to let experimenters who have the Glafkides table know that there are errors, omissions and uncertainties. I hope to gather all of it together and post more information on part #9 which pretty much renders the tables useless.

PE

Ray Rogers
02-13-2011, 09:26 PM
Well yes, in that table, there is a big goof.
But I don't see that nor even the total of all the omissions and goofs as a disaster.
The ingredients he goofed up on are not particulary crucial players in the overall picture.

They appear to me as final additions not a supercoat.

Good to know, but not really all that important.

I have all known versions and one or two that were never published - but other than out of curiosity, I never felt the desire to "copy" them. (Out of the question anyway)

I am much more interested in your emulsions! ;)
They are The Real Mystery IMHO!

My2c

Photo Engineer
02-13-2011, 09:39 PM
Ok Ray, then make 5 contrast grades of Brovira from that formula if it is so obvious.

Sorry, but the actual corrections are obscure!

PE

Hexavalent
02-13-2011, 09:59 PM
Well yes, in that table, there is a big goof.
But I don't see that nor even the total of all the omissions and goofs as a disaster.
The ingredients he goofed up on are not particulary crucial players in the overall picture.

....

I have all known versions and one or two that were never published - but other than out of curiosity, I never felt the desire to "copy" them. (Out of the question anyway)

I am much more interested in your emulsions! ;)
They are The Real Mystery IMHO!

My2c
Ray,

Please share these deep dark mysterious Brovia 'goofed up' ingredients. It would help those of us who Would like to replicate Brovira

Ray Rogers
02-13-2011, 10:06 PM
The second part is somewhat too vague to respond to...:confused:

Is the first part rhetorical? :wizard:

Ray Rogers
02-13-2011, 10:17 PM
Ian,

If I understand what PE said, he gave you most of the corrections.
I can fill in the holes he left, but as I said before, there are many versions.

If you are just asking for the items in #9 that PE mentions above as being a "kinky"
(or would that be a Jog?) dislocation (Sorry-dumb emulsion makers joke)
yea I could do that. Is that what you meant?

Photo Engineer
02-13-2011, 10:48 PM
Ray, since I am busy preparing workshops and the book, why don't you do it.

Thanks.

PE

Ray Rogers
02-13-2011, 11:09 PM
Ray, since I am busy preparing workshops and the book, why don't you do it.

Thanks.

PE

You sound serious...

Photo Engineer
02-14-2011, 09:02 AM
Ray;

I was handed the 5 formulas in class and asked to comment. Since enlarging papers were outside of the scope of the workshop, I promised to look into the matter and give the students my comments. Finding such errors when I did the actual research surprised me so I decided to post the results here. I did not say anything in the workshop about this subject.

So, if you have the correct data, please post it here. Otherwise, I have to create a table of corrections and scan it in. Why not do it for me if you have the same thing at hand, and do it with my thanks and those of the rest of the interested parties. BTW, this is NOT my enlarging paper formula by any means. The only similarities are the use of Silver, halides and Rhodium. It uses a Sulfur sensitization and inactive gelatin. There is quite a difference! ;)

PE

Ray Rogers
02-14-2011, 09:16 AM
So everyone present got a copy already?

Photo Engineer
02-14-2011, 10:00 AM
I believe that everyone was given a copy by one of the students. That is the incorrect copy as attributed to Glafkides. I was told that this same incorrect copy is somewhere here on APUG. And, you said above that you have a copy.

PE

Ray Rogers
02-14-2011, 10:12 AM
OK so I will just post the corrections.
They will not be made easy reading
but they should not be too hard to follow,
if one has table 9... (unseen by me):

The 7 ingredients:
1st item should be gelatin (but it does not appear in the table)
Thus there are only 6 ingredients to be found in the table.
Items 2-7 are those, in the order given

The Amounts:
1st row of amounts given are the amount of gelatin, (should be grams but appears as cc)
2nd row of amounts given is for the first item listed there,
3rd row of amounts given is for the 2nd ingredient listed there
4th row of amounts given is for the 3rd ingredient listed there
5th row of amounts given is for the 4th ingredient listed there

Amounts for the 5th ingredient listed there ARE MISSING!
Those amounts should be zero,
except for emulsion #2 (reading l to R),
which should be 0.1 cc

6th row of amounts given is for the 7th ingredient listed there

Note that there may be other versions wh. I have not examined here.

Photo Engineer
02-14-2011, 10:19 AM
Thanks Ray.

PE

Ray Rogers
02-14-2011, 10:41 AM
Happy to be of use.

Photo Engineer
03-04-2011, 03:47 PM
I finally located a copy of Glafkides. I was looking under the wrong book title!

Anyhow, Volume #1, page 342-343 gives the table posted here on APUG and handed out at our last workshop. The original in Glafkides is wrong, as described in the OP and as corrected above. Glafkides does mention in the text the need to use different gelatins for the different grades of paper, but gives no details.

The interpretation of step #9 is still ambiguous due to the original German and the English translation error.

PE