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Mainecoonmaniac
12-20-2011, 10:28 AM
I really like this website, but this is way over by head.

http://thelightfarm.com/cgi-bin/htmlgen.py?content=19Dec2011


Enjoy and happy holidays!

Bill Harrison
12-20-2011, 11:47 AM
Keep reading it over and over and it will start to make sense... it's not easy at the beginning

Jerevan
12-20-2011, 01:16 PM
Yes, it is a great resource, take your time, and things will get clearer. If you feeling like jumping head first, I suggest to buy some liquid emulsion and get a feel for it. Unless you don't want to try out Kevin Kleins dry plate recipe: http://thelightfarm.com/Map/DryPlate/Recipes2/DryPlatePart3.htm to get down to basics.

Mainecoonmaniac
12-20-2011, 08:33 PM
Now that's intriguing. Are there glass plates and glass plate film holders available?

wildbillbugman
12-20-2011, 10:13 PM
There are many glass plate cameras and glass plate holders for sale on Ebay. The Light Farm is NOT complicated. In fact, it is probably the most pain-free way to get started in emulsion making. But,for me, ther ain't no substitute for actualy doing it. I made four emulsions befor I had one that did not fog completely.. Now, I have made well over 200 emulsions. Do try making Kevin's emulsion,then Denise's emulsion #1. Don,t let people intimidate you by making it out for more than it is.
To heck with pre-made emulsions. They are overpriced. Bill

Photo Engineer
12-20-2011, 10:22 PM
There are many sources for glass plates, both new and vintage. I have about ten or more vintage plates right now that I bought for about $10 or less each.

As for the light farm, it is a very good resource for information up to about 1865. I am of the opinion that the texts do not give enough information on how to make the transition at that time and more recently and also that too much reliance is made on the work of Woody Thomas (Woodlief Thomas), who was NOT an emulsion maker, but rather an editor. I knew Woody personally, and he was a great process engineer, but not an emulsion chemist or product engineer.

One has to be careful, without criticizing Denise, to avoid the problems with publishing emulsions at that time. Kodak kept a tight reign on what could be published in the emulsion arena, and Grant Haist has complained to me bitterly about the editing done to the formula that he published for a lith emulsion.

The ward here is Emasculation! Sorry!

Denise is dong a good job, but only with what she can read in the published literature. That ties here hands in a sense.

PE

Hexavalent
12-20-2011, 10:41 PM
"Lantern Slides" can sometimes be found for next to nil at garage sales etc., - the glass is easily stripped clean. Lucky for me, the set I've got fit my 1920's Kodak folder. After much practice, I can pour an even layer on a slide without covering myself and the floor :)

It is not difficult to make a slow, color-blind emulsion, however a more 'modern' emulsion ( repeatable, good keeping properties, latitude, pan sensitive, etc.,) is not a trivial matter.

Warning: emulsion-making is very addictive! It has eliminated my social life, which is actually good, as I can now spend all my money on silver, chemicals, lab gear and paper instead. :p

Have fun!

Jerevan
12-21-2011, 06:44 AM
PE,

why the year 1865? Because the civil war ended? :) Seriously, do you mean washed emulsions and dry-plate technology harkens back that far?

EDIT: forgot about the dry collodion stuff - so nevermind. :)

I am of the mind that not everyone has the means to develop a fullblown lab, to make more modern film emulsions. I am with Ian that making modern emulsions seems to be a major undertaking. In this case I find it worthwhile to also have a different direction which is more basic and hobby-oriented, with all the trials and errors that entails.

The more people who are interesting in emulsion making, as a means of artistic expression, the better. Even if it starts out with store-bought liquid emulsion on a piece of paper or glass.

Both ends of the spectrum are needed, I think. Even if some of us are colorblind moles while others are panchromatic butterflies... :)

dwross
12-21-2011, 08:36 AM
The confusion between wet plate and dry plate is a common one. The wet plate collodion process was developed by Fredrick Scott Archer in 1851. It was ‘photography’ for twenty years. Wet plate gave us both the haunting documentation of the Civil War and the earliest iconic images of the American West. But, most practitioners could hardly wait to be quit of the process. Many attempts were made to produce a dry collodion process, but none had enough sensitivity to become popular.

Silver gelatin photography and ‘dry plate’ was invented in 1871 by Richard Leach Maddox, and plates were available commercially by 1873. In 1884, Josef Eder developed orthochromatic emulsions, and in 1889, Kodak started putting emulsion on nitro-cellulose film. By the 1940’s, silver gelatin emulsions were available in so many forms and variations of stunning beauty, most of which have never been surpassed, that many consider that time frame the apex of silver gelatin artistry. Yet most have been lost to us commercially. There are countless d.i.y. /artistic possibilities available to us today without ever worrying about producing a T-grain... Addictive, indeed!

Another common area of confusion is the role of a book editor. He or she is responsible for the organization of a book, not --by and large -- the writing. The authors of the SPSE Handbook are a who’s who of emulsion engineering and chemistry greats, and as can be expected among such a crowd: intensely peer-reviewed.

c.d.ewen
12-21-2011, 09:56 AM
Mainecoonmaniac:

A good source for glass plates is down in Worcester, MA: S I Howard Glass (http://howardglassco.thomasnet.com/viewitems/soda-lime-glass/soda-lime-glass-2). I use the 1.2mm soda lime glass. They do have a $50 minimum order, though.

You can find wooden plate holders on eBay, but sellers never know a film holder from a plate holder. The best 4x5 plate holders are Linhofs, but they've become terribly scarce. Be careful, however: you want the ones with the plate ejector (auswerfer) on the side. Look for an arrow on the front of the holder; no arrow = no auswerfer.

How many toes does your cat have?

Charley

Photo Engineer
12-21-2011, 10:42 AM
PE,

why the year 1865? Because the civil war ended? :) Seriously, do you mean washed emulsions and dry-plate technology harkens back that far?

EDIT: forgot about the dry collodion stuff - so nevermind. :)

I am of the mind that not everyone has the means to develop a fullblown lab, to make more modern film emulsions. I am with Ian that making modern emulsions seems to be a major undertaking. In this case I find it worthwhile to also have a different direction which is more basic and hobby-oriented, with all the trials and errors that entails.

The more people who are interesting in emulsion making, as a means of artistic expression, the better. Even if it starts out with store-bought liquid emulsion on a piece of paper or glass.

Both ends of the spectrum are needed, I think. Even if some of us are colorblind moles while others are panchromatic butterflies... :)

Well, my post should have said "1965" which is about the date range of the last of the emulsions in the book that woody Thomas edited. And that is about the time I was helping edit Grant's Book (1970 or thereabouts). Sorry for the type. My eyes are in very very bad condition after the last few weeks. I am also fighting a keyboard that likes to miss keystrokes and that doubles others.

Also, I forgot to add that the Formulary now sells glass plates in 4x5 and 8x10 and will custom cut as well. I have also found a source for old plate holders and for hand made new holders but the latter I dismiss due to the extreme in price.

In books of the sort that are referenced here, one must remember that both the editor and the author are given guidelines of what may or may not appear in a given work. In this case, that would cover a lot of people and a lot of information. When I published anything, my work was both edited and "vetted" by a group of people who could "veto" words, phrases, or even whole topics thus leading to a severe "emasculation" of the topic, and thus the emulsion published in Haist is actually nearly unusable due to omissions forced by the vetting process.

You may note that some of the formulas use Cadmium. At the time of writing, Cd was obsolete and too dangerous to use in a common lab and had been replaced by at least two organic chemicals. The wash is given in terms of conductivity, and the addition method of the first silver is given as what is essentially a "dump". Mixing speed is vague. The gelatin used is assumed as active. This all points to formulas from the 1945 era, as they read much like those of that time. Specific addenda for keeping and other photographic qualities are not mentioned.

That is the problem that I see. So, one can make a simple emulsion such as these, but there are about a dozen added sentences to each one that would significantly improve each and every one.

Here is an example. To every formula, one can add TAI (Tetra Aza Indene) as described by Jim Browning and available from the Formulary. Use of this chemical will just about double or triple the keeping of the coatings and will lower fog! Washing to a given vAg would also improve the emulsion, but even using conductivity, a concrete method of measuring conductivity would help and none is really given in the article!

So, that is my take with this and why I think that the work must be modernized. And, BTW, reading my book for the last time I find that I could have done a much better job. My problem is that I am just running out of time and patience. ;)

PE

PE

Jerevan
12-21-2011, 11:42 AM
PE,

thanks for the elaborations. I am sorry to hear about your eye condition - I hope it gets better. Your contributions are very valuable.

I think that even if you find faults (who doesn't with his own work?) with the book, it is much, much better than no book!

Mainecoonmaniac
12-21-2011, 11:54 AM
Hi Charley,
You can spot a cat lover mile away. Thanks for the referral for the glass company. I'll take a look. Searched on Ebay and haven't found any plate glass holders. I'll keep searching. Again the process is very intriguing. Looks like you can make a batch and refrigerate it until you need it. I would like to coat a bunch and store it. I'm sure the emulsion is good for coating paper for prints.

Photo Engineer
12-21-2011, 12:52 PM
The average emulsion can be stored as a gelled material at about 3 deg C for nearly a year or more. With a better preservative against bug attacks it can be extended to about 2 years or so. Fog growth can be inhibited by TAI at the proper level.

Also, the emulsions that I have been making are so repeatable that I am now blending mixes, so I can make 400 g this month and two months from now, down to 200 g, I can make another 400 g, mix them and have 600 g of good stuff. I see no reason why the slower emulsions of any sort that I have read on-line could not be blended in this fashion.

PE

Jerevan
12-21-2011, 01:17 PM
I am going to do some legwork on this TAI, see what I can find out.

Photo Engineer
12-21-2011, 01:37 PM
TAI is quite benign AFAIK, but I don't have the CAS # OTOMH and the IUPAC name escapes me right now. It is used in Europe at all film manufacturers and since Fotoimpex is now selling the DVDs, maybe you can get it through them. I'll look up the # here somewhere.

It was first patented by Birr of Agfa fame in the '30s.

PE

Jerevan
12-21-2011, 01:55 PM
By googling the name, taken from the Formulary homepage, I got CAS# 2503-56-2. Great to know that Fotoimpex is selling the DVDs! Yes! :)

I gather it has this little name too: 4-Hydroxy-6-methyl[1,3,3a,7]tetrazaindene.

As for emulsion stabilizers, this thread seems to be a worthwhile read: http://www.apug.org/forums/forum205/49564-photographic-emulsion-stabliizers.html

Photo Engineer
12-21-2011, 02:13 PM
I think that is an excellent book. Lots of good information in there. I had forgotten about that thread entirely.

I think you have the right CAS #.

Go here: http://www.fotoimpex.de/cgi-bin/shop/de/index.cgi?func=det&artnr=2452&rub1=Literatur&rub2=&wkid=78689058633599515&session=1&nocache=1324397154

for the DVDs in Europe.

Thanks.

PE

wildbillbugman
12-21-2011, 02:20 PM
With regard to glas plates, Tru- Vue galss is a fine glass fot plates AND final support. It can be found on Ebay and can be cut to order. I use it for 5x7 glass plate negatives, and for my final support. It is not quite water-white($$$$) but is far less green than ordinary window glass.
Bill