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kbrede
12-06-2012, 10:31 PM
One more question. Is making your own photographic paper cheaper than purchasing or not? I wouldn't be doing this for saving money, I'm just curious. :)
Thanks,

Photo Engineer
12-06-2012, 10:52 PM
Good work Denise.

Mark and I will be teaching a course in March. I urge you all, interested in emulsion making, to take the workshop at George Eastman House. http://www.eastmanhouse.org/events/detail.php?title=photo-workshop-3-2013

The person in the photo is a student at our last workshop and is an Academy Award winner!

We have some great people coming to GEH to learn about photography. Join us for an amazing experience!

PE

marenmcgowan
12-06-2012, 10:53 PM
Sweet...I love this site. I'm currently trying to get a darkroom set up and this is the kind of thing I would love to be doing. THanks for the awesome resource!

dwross
12-07-2012, 08:16 AM
One more question. Is making your own photographic paper cheaper than purchasing or not? I wouldn't be doing this for saving money, I'm just curious. :)
Thanks,

Kenton,

The short answer is "it depends."

Here's the long answer: The papers I use most frequently are Arches HP 90 lb and 140 lb. At Dick Blick right now they're $4.19 and $4.83 per 22"x30" sheet. I keep my eyes (and inbox) open for specials, especially the free shipping ones, so I end up paying less, but let's say $4.50 a sheet. I use 2-1/2 sheets per recipe that calls for 5 grams of silver nitrate. I get eight to ten 8x10-inch sheets, plus enough selvage for test strips (or a lot of 5x7 pieces.) That comes out to $11.25 for paper and approximately $5 for silver nitrate = $1.50 to $2.25 per 8x10 piece of printing paper).

Beyond the one-time cost of the tools, paper and silver nitrate are the only real expenses. Depending on what you can raid from your kitchen, and how many of the items I listed you might need to talk to Santa about, (http://thelightfarm.com/cgi-bin/htmltutgen.py?content=02Dec2012) the equipment costs to start up will range from zip to less than $250. Since you need some of the tools and materials even if you're printing with commercial paper, how you count those costs is an individual matter, as is your philosophy of amortization.

Another factor in determining cost is the value you place on time. Making your own materials isn't "efficient" in the sense we've all come to expect efficiency. No craft is. Having said that, basic paper pulls together really fast. If you don't count drying time, I spend less time per recipe than I do making a loaf of bread.

Last but not least, as you hinted, what price satisfaction, or heck, just plain fun?

Hope you give this a try!
d

kb3lms
12-07-2012, 08:48 AM
Just to add to what Denise said, the complexity of the emulsion process at a basic level is about the same as baking a cake from scratch. (raw ingredients vs a "box cake") Now that level of effort isn't going to get you "Tri-X from your basement," but it will get you something quite usable. After that, it is how much do you want to experiment or try to invent so it's up to you.

Also 50 or 100 grams of silver nitrate goes quite a long way. My last batch of TLF2 has given 7 120 rolls plus extra used for testing, single frames, etc,. for 6 grams AgNO3. Total materials involved in that batch probably cost under $10 (US).

P.S. the term "proof" in regards to liquor gives the alcohol content. It is double the actual percentage of alcohol. So 100 proof is 50% alcohol.

P.P.S Thanks for the word on Chemsavers. Have bought from them through eBay but did not know they had a web site. Watch them for AgNO3. Occasionally they have a sale on it.

kb3lms
12-07-2012, 09:08 AM
Lastly, one other (OT) thing I will post here since this thread is getting some traffic.

CHEMSAVERS on eBay has listed at this moment 250mg of 1,1′-Diethyl-4,4′-carbocyanine Iodide, otherwise known as kryptocyanine for $27 plus shipping. This is one of the sensitizing dyes on PE's list and, IIRC, is a sensitizer for the red and near infrared. Go on eBay and search on "carbocyanine."

This is why I say to watch eBay. Maybe it is available through their website as well.

I'm not going after panchromatic emulsions at this time so I'm not picking it up but thought someone else in the forum might be interested.

Now, back to the topic...

-- Jason

dwross
12-07-2012, 09:10 AM
I love the scratch cake v. box cake analogy. Spot on.

Need to clarify an important point though. It's a frustrating (to me) source of confusion.

"Silver gelatin emulsions" is a big universe, covering not just space (i.e. products available commercially today), but also time (i.e. products available at different times since 1880.) That part is pretty general knowledge. What can be confusing are the very real differences between paper emulsions (almost all neutral, unwashed, unsensitized -- don't worry about what those terms mean now: all will be revealed! -- just think old-timey) and negative materials emulsions -- which range from basic dry plate to the most sophisticated modern film.

A basic paper emulsion (minimal tools and materials), well-coated, is virtually indistinguishable from commercial. I often compare a handmade recipe to Lodima paper and if I coat on glossy, commercial baryta, I have to make sure I take careful notes as I process or I won't able to tell which is which after the prints are dry.

It's possible to leave "hand of the maker" tells on handmade paper, but that is a creative decision, not a technical default.

dwross
12-07-2012, 09:28 AM
Thanks! Scott and Jason for the info about Chemsavers. They're a great resource that has managed to escape my notice. No longer. Bookmarked!

kb3lms
12-07-2012, 11:18 AM
Is Bostick and Sullivan on your list? I have found decent prices on some things there, such as gold chloride.

Jerevan
12-07-2012, 11:47 AM
Good to see things moving along! All thumbs up! :)

Photo Engineer
12-07-2012, 01:02 PM
Dont forget that the Formulary has a number of unlisted chemicals for emulsion making such as PMT (Phenyl Mercapto Tetrazole) and TAI (Tetra Aza Indene). These are excellent antifoggants and stbilzers that are used in a number of emulsions. With TAI (supplied as a powder or in solution) you can make your emulsion keep for a long time with no change in properties.

PE

anikin
12-07-2012, 02:53 PM
With TAI (supplied as a powder or in solution) you can make your emulsion keep for a long time with no change in properties.

Liquid emulsion or the coated film/paper?

Photo Engineer
12-07-2012, 04:52 PM
Actually, both!

PE

kbrede
12-08-2012, 10:25 AM
I've got questions about a couple items that need to be purchased.

I've got a 1/4" 11x14" piece of glass that I plan to use for contact prints in my darkroom. I haven't used it yet but I thought I could either lay paper, negs and glass on the baseboard, or get some thin foam to lay on top of the baseboard first. Will this work for the project? Or do I need to purchase the contact frame that was suggested?

Also we need a "reliable" scale that measures as low as 0.01 g. First could I get some recommendations as to which ones are "reliable?" Also what's the top end the scale should be able to measure? Some are 20g, some 500g, etc.

Would either of these fit the bill?

http://www.amazon.com/US-Balance-Digital-Scales-Silver/dp/B00123AVTO
http://www.sciencecompany.com/Parts-Counting-Compact-Scale-2000g-x-01g-P16791.aspx

Thanks,

anikin
12-08-2012, 10:53 AM
Actually, both!

PE
Cool! I'll get some. Which one is better? Or should I get/use both?

dwross
12-08-2012, 11:02 AM
Kenton,

The one from Amazon looks like a great scale.

The two scales are a perfect example of the trade-off between upper and lower end precision -- at least for any scales I can afford. The rule of thumb I was taught is that you want a decimal point of measurement beyond what you expect to weigh. i.e.: If a recipe calls for 5.5 g of doodlebugs you'll want a scale that measures to 5.50 grams. I have two scales that have almost the same ranges as the two you have here. I almost never pull out the 0.1 scale. I just don't have the room for two scales out and the work-around isn't a big deal. If I need 150 ml (grams) of water, I weigh out the water in a couple of divisions.

Important, though: You'll want a calibration weight, or even better, a set of them. The instructions for calibrating the scale will be included with your model. It's very easy, but very important.

Re: contact printing under glass. It can be done. It will be fine in the beginning as you're learning and deciding if all this is something you really love doing. But, in the long run, especially with handcoated paper that isn't dead flat when it dries, the tight contact afforded by a good spring-back frame can't be beat.

btw: excellent questions!

Photo Engineer
12-08-2012, 02:33 PM
Cool! I'll get some. Which one is better? Or should I get/use both?

They each have slightly different uses so I would get both.

If you are in Rochester for any reason, I can give you a tiny starter amount for your lab. Otherwise, the Formulary is your best bet. Sherry knows where the bottles are kept.

PE

Photo Engineer
12-08-2012, 02:35 PM
For contact printing, I use a metal framed heavy glass printer that I bought locally at a photo store. It is so heavy that no wrinkled or curled paper has defeated it! :D

Denise is right thou;gh. You want something heavy to insure flatness.

PE

Hexavalent
12-08-2012, 07:10 PM
When looking at the specs for weigh scales, note that accuracy and resolution are not the same thing!

dwross
12-10-2012, 08:31 AM
Hi Ian,

Nice to see you here again. I hope this means you've cleared your work load enough to get back to making emulsions!
d

p.s. In case anyone has missed it, emulsion101 is more than Ian's website, it is a silver gelatin emulsion forum he established.