I need your help

[rowland_mowrey]

Today, I passed another benchmark, achieving ISO 100 speed with a

paper negative using one of my own homemade emulsions. It was only

sensitive to blue light. I expect higher speeds in the near future,

assuming this was no fluke and I can repeat it.

 

Having done that, I now am faced with a perplexing problem and a

question for everyone out there. It was posed to me by a very

reputable person in an exchange over my work on emulsions and the

workshop I mentioned in another thread a while back.

 

Here is the question:

 

"Why would you want to attend a workshop to learn how to make and

coat emulsions when there are products like Liquid Light that you can

buy"?

 

I answered as best I could, but hearing from you all would be a great

help to me.

 

Disinterest and negative opinions are very welcome.

 

Thanks.

 

Ron Mowrey

[skygzr]

Why would you want to....

 

"Because you feel like it" is a perfectly acceptable answer. It's art, after all. It doesn't have to make sense.

[randrew1]

Why would I bother to take a picture of Old Faithful when I can buy a post card?

[john_shriver]

I think Liquid Light is a "paper speed" emulsion -- slow. Making something fast enough to use for instantaneous photography is a different challenge.

[lex_jenkins]

Because you can.

 

Because it's there.

 

Because products like Liquid Light might not always be available. Knowing how to homebrew emulsions could be very useful.

[robert_landrigan]

Arrogance.

 

I mean, photogs are an arrogant bunch - we steal time, after all:) Being able to point to a

print on the wall and say "I made that" - including the film - well, that's art snobbery that

can't be beat!:)

 

I'm a black and white film, and digital color shooter - I'd love to be able to make my own

negative, if only for the challenge and bragging rights:)

[reinhold_schable]

Ron...

 

Keep it up!

Don't stop now!

 

We need an answer for those smug, smart*ss digidorks who ask: "what're ya gonna do

when you can't get film for that old contraption"

 

I shoot 8x20, and I can already visualize what a photo from a paper negative would look

like... yum...!

 

Go gettum.

 

Reinhold

[christiaan_phleger___honol]

Because in my reasonable lifespan, I may have to create a photographic emulsion from

scratch for myself because the large manufacturers have ceased production. Much of the

advanced photographic knowlege seems to be tied up in Non-disclosures and patents and

those older photo engineers aren't getting any younger. The info on how to make one of

the basic elements of photochemical based could be lost or more likely the lack of access

to the more developed research the could set back photography many many years. I'd

prefer if more people knew how to make emulsions.

[gary_deal]

I second Kevin's reply, "because I feel like it". Or, because I can, because I like that kind of thing, because it's the hunt, AND the kill.

 

You might ask that same person "why would anyone cook their own food when they can simply open a can?"

 

I'm also interested in how you broke the ISO 100 barrier - how's the resultant granularity?

Ron, I can mail you some pinacyanol chloride (red sensitizer) if you like, just email me.

-Gary

[chris_waller]

I know of painters who like to grind their own pigments and make their own paints. Why do they do it when they can buy tubes of paint? Because it increases the depth of engagement in the medium. Most of my photography is concerned mainly with the subject, but sometimes I take pictures purely to explore further the medium of photography. I can understand also why sculptors can spend hours chipping away at a block of stone - it's the tactility, and contact with the medium.

[stephen_allan]

The reason I have continued using film, is that I love the feeling when I remove that strip or sheet of plastic from the developing tank, and it has _my_ images on it. I know the mechanics and the chemistry of the process, but it still feels magical.

 

To be able to do everything from coating a negative to printing it? Oh YES! That is definitely worth a workshop to learn how to make and coat emulsions.

 

Steve

[chuck_pere]

I think that one important reason would be the ability to vary the emulsion to get a look that you want. To play with different mixes and see what comes up. But maybe you can get that with the store bought stuff. I've never used it. Other reasons are more technical. But these are interesting to many people.

[James G. Dainis]

Just because some people like to sit around on their butts watching mind rotting TV is no reason why they should question others who actually know how to and enjoy using their brains. (Said with a significant glare.)

[James G. Dainis]

Ron,<BR>

I'm sure the person who asked you was genuinely interested in the value of doing it. Aside from the challenge to learn/discover new things and finding it interesting, what was your response to him?

[j.w.]

Ron, I'm predominantly a pinhole photographer, using paper negatives more often than sheet film.

 

I've learned to control preflashing to achieve a more normal tonal range, and also appreciate the orthochromatic look.

 

A film-speed paper negative would be a great boon to pinhole photographers. Keep it up.

 

Perhaps you could post some of your results to the f295.tompersinger.com website, under the "Darkroom" category. Lots of pinholers there would be interested.

 

Thanks for posting this. Keep us informed.

[rowland_mowrey]

Guys;

 

Thanks for the answers. My response to this person was much along the lines of your posts, but I'm not objective about this, so I needed to see if others felt the same way. Objectivity counts!

 

As for the emulsion, here are more details.

 

It is an ammonia digest (UGH - trying to simplify and eliminate this by using another method), with about 3% iodide. It was unwashed and unfinished, but allowed to digest too long (my error which made it a bit foggy on paper support) and was coated at high silver and gelatin. It was about 700 mg/sq ft of both or about 2x over current high silver production films.

 

The paper was cut to fit a Polaroid film holder and exposed at ISO 100 in my Mamiya RZ67. It was developed for 1' in Dektol 1:3. I do plan on making a washed, finished and sensitized (ortho) version and coat it on film and paper in the near future.

 

Finishing (sulfur + gold) will gain about 1 stop, and ortho sensitzation will gain another if I'm lucky. Coating on film will lose a stop due to lack of back reflection. Adding an AH dye for sharpness will lose another stop, so net I will remain at ISO 100 with better overall quality in sharpness and grain (being on film support with AH).

 

I am using paper for simplicity. I can test quickly without washing, and I can get paper more easily than subbed film. I will be using film ASAP and will include all of this and more in the workshop.

 

Ron Mowrey

[henry_a]

I'm not sure I'd be all that interested in making the paper but I am sure I'd want to use some version of what you're making. An 8x10 original paper print without a negative sounds very appealing. So are you making a negative emulsion that will ultimately be applied to a film base or can it be a positive emulsion on paper? Or am I completely confused about your direction?

[rowland_mowrey]

What I am doing will create a set of negative emulsions of various speeds and contrasts and which can be applied to either film or paper. I am using paper right now for convenience, cost, and availability.

 

Subbed film is harder to come by and more expensive. Why experiment on it when I can use paper.

 

Thank you all for your insightful and thougthful answers.

 

Ron Mowrey

[malcolm_tentt]

{Its like a cook making an omlet and not knowing what an egg is.}

 

No, an apropos analogy in this case would be that cook straining to lay an egg.

[poul]

are you planning to post a detailed recipe somewhere? i would love to try this in large format camera. i am scanning all my negatives, so as well may scan a sheet of paper...

[James G. Dainis]

The only time I fooled with paper negatives was loading regular photo paper into an 8 x 10 film holder. It took a fairly long exposure in the 8x10 camera at f/64 (memory fails me on the details). The paper negative looked okay but contact printing gave a very soft look. A direct positive would be interesting. Totally unique but laterally reversed like tintypes/ambrotypes/daguerreotypes.

[rowland_mowrey]

The formulas for the emulsions will be finalized by the time of the workshop. At that time, all participants will get copies of the formulas as part of the workshop and will have an opportunity to make any or all of them.

 

After that, I am trying to work out a method to publish them for the benefit of all (samizdat?).

 

The paper negatives I make are acceptable, but I want to do better. I scan them in, flip them horizontally so they are not reversed, and then make a positive to view the quality on my monitor.

 

The exposure for the ISO 100 was 1/250th at f8 in full sunlight. The previous example, at ISO 25 was 1/125th at f5.6, or 2 stops greater. The emulsion was only blue senstive in this case, and therefore greens were black as were reds. The test object was a MacBeth color checker propped against some hedges.

 

My next step is repeating this emulsion to insure it can be done with good results more than one time. I will then go on to chemically and spectrally sensitizing it (sulfur + gold, then ortho sensitzing dye) to gain more speed, and will add an AH dye for sharpness. It will be more complex to make and will really not be faster, but should have higher overall quality (less fog and better keeping along with better sharpness in the coating).

 

The paper speed emulsions and slow camera speed emulsion take about 1/2 hour to make and are quite easy and repeatable. This emulsion is much more complex taking over an hour, and includes up to a 3 day workup period. I don't like that for the average person. I am trying to stick with the idea of the 30s or 40s, but I may have to abandon that in favor of further simplicity.

 

Ron Mowrey

[25asa]

Keep it up Ron. I hope the workshop goes well. I'd be interested in buying your book when it comes available.

[patrick_gainer]

You will be able to coat these emulsions on glass, I presume. It would be interesting to use a reversal process with coating on paper. Perhaps by putting the emulsion side of a glass plate negative against a piece of white paper and photographing through the glass you could avoid some of the speed loss.

 

Engineers are stranger than scientists. We have no idea what cannot be done, so we try all kinds of things, like going to the Moon.

[rowland_mowrey]

Patrick;

 

The entire thrust of this, getting away from paper negatives, is to avoid the sharpness loss due to scatter from the paper fibers, and also to avoid the appearance of grain that you get from the paper grains.

 

Other than that, this can be coated on any surface you want.

 

You just must be aware that you will lose speed on film, glass or even to some extent RC support due to their physical properties. The RC changes speed not mainly due to loss of backscatter, the loss on RC is more chemical than physical. The impermeability of the support when compared to FB papers changes the chemical balance in the emulsion.

 

So, these reasons are the main ones that are not evident unless you have the appropriate engineering background. There are quite a few other factors as well. Why don't you come to my workshop?

 

Kind of like going to the moon, but different science and engineering. It might be revelatory to you.

 

Ron Mowrey