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hrst
09-23-2009, 06:31 PM
Thanks!!

How I "measured" the "about ISO 10":

I adjusted the enlarger light to approximate sunlight (added some cyan+magenta) so the comparison would be "fair".

Then I exposed my step wedge film (I have made it before on BW film) to Agfapan APX100 at a specific exposure and processed in XTOL 1+2 for 3 mins.

Then I opened lens three stops and exposed my film and processed it in the same way.

After processing, I noticed that the lowest density wedges on my film and APX100 match quite closely. And, because I opened lens three stops, it's ISO 12,5. Very precise :D.

Emulsion
09-24-2009, 07:37 AM
Hrst,

Great results! Thanks for posting your process and results, keep up the experiments. Inspiring!

Emulsion

hrst
09-24-2009, 04:14 PM
This emulsion is fantastic!!

We took a real photo at ISO 10. Indoors, it was 2 seconds at f/2! We made a print on Kentmere multigrade paper. It prints nicely on normal contrast. Print looks very good. The attached scan is not so good (scanner is something like 15 years old).

Developing is much more fun than with normal films, because the emulsion loosens from the base. You have to be very careful!

This image was originally 35 mm image! Still the grain is not bad at all! But our process has a super cool INTERPOLATION system (just like DIGITAL ZOOM but analog!): emulsion stretches during processing and a 35 mm frame ends up almost as a 645 frame :D.

OH YEAH!

Photo Engineer
09-24-2009, 04:40 PM
Very nice, congratulations.

Is this the sulfur sensitized version? You could now add Erythrosine to make an Ortho sensitive version. This would probably gain you a little camera speed due to the added sensitivity.

Best wishes.

PE

hrst
09-24-2009, 04:59 PM
Thank you.

This is the most sulfur sensitized version of the three, but they all gave the same results in step wedge test so this is same ISO10 as the unsensitized one. Heat treatment after adding the hypo was insufficient.

Next, hardening (and better base, or a subbing layer). Then, better sulphur sensitization and erythrosine. Then we may start experimenting with chlorophyll to try to make a panchromatic film! We have a BW video camera (IR sensitive), IR leds and a small monitor. Not quite the same as IR goggles but better than in completely dark.

hrst
09-24-2009, 10:52 PM
I've read here that erythrosine has to be added in a specific way to make it work properly. Can you give some hints how (and how much) to add it and how this differs from the addition of other kind of dyes?

Photo Engineer
09-24-2009, 11:00 PM
I cannot due to the differences between your emulsion and mine.

I would suggest about 50 mg of erythrosine / mole of silver, added as a 1% solution in water. That is a good starting point.

PE

hrst
09-25-2009, 12:33 AM
Version 0.01

:cool:

Photo Engineer
09-25-2009, 10:15 AM
They look very nice and quite similar to my film and plate coating blades.

PE

Kirk Keyes
09-25-2009, 12:43 PM
Great job with the results!

Ray Rogers
09-25-2009, 02:25 PM
OH YEAH!

Is that one of you in the picture?
Looks like a nice welll equipped workshop....

Ray

wildbillbugman
09-25-2009, 06:39 PM
Looks like the grain is very small.
Bill

hrst
09-25-2009, 07:02 PM
Is that one of you in the picture?
Looks like a nice welll equipped workshop....

Ray

Yeah, I took the picture and the other one of us is in the picture :). He's making a LED light at our university's electronic club (blue light is on in the picture ;)). And we are making the emulsion in camera club's darkroom. I'm a member of board in both of these clubs. It's nice to have clubs like these!

hrst
10-22-2009, 03:27 PM
We tried coating this emulsion to a matte plastic sheet we have here (I don't know what it is. Probably some PET with processed, matte surface.) to make a kind of enlarger paper. It worked kinda well! First of all, the emulsion doesn't loosen off in processing at all (this is unharneded!), contrast is almost ok for enlarger use. This is maybe a stop or two slower than most enlarging papers. It looks quite cool when you have some light source behind the "paper".

Here's a digital photo of this print taped to PC monitor to give some light thru the print. Original negative is Fuji Neopan 1600, processed normally. On the right side emulsion was so thick that it took too long to fix, so I stopped fixing after 3-4 mins. It seems that very thick emulsion results in a bit slower speed and more contrast, and more glossy surface.

totalamateur
10-22-2009, 06:18 PM
That's really great!! Thanks for posting pics of your work!

Photo Engineer
10-22-2009, 06:55 PM
Excellent work. Good luck guys. Keep going!

PE

Photo Engineer
10-22-2009, 08:21 PM
Here is a setup I am constructing for a high speed make.

It is taking a lot of white light rehearsal before I commit!

The blue objects in the lower left center are the two pump heads. Above them are the beakers that will contain silver, 2 salts and dopants. On the right is the temperature controlled hotplate with mixer.

Note the creative use of clothspins to hold tubing. :D

Out of frame in the center is a burette holder for my burettes so that I can add additional solutons at a given rate.

I am at present working on the electrodes needed to insure that I am at the right vAg for this high speed make. I am going to attempt ISO 400 but who knows.... :( The phase of the moon might be wrong.

In any event, your results at the start are better than mine. I came out of a million dollar lab and tried to do it on a shoestring. When I finally came to my senses, I did a major revision of my operating procedures and now am moving ahead one step at a time from basics.

Congratulations guys.

PE

wildbillbugman
10-22-2009, 09:04 PM
:)Guys from Finland,
Realy great results for a first try. It took me 5 tries to figure out why I was geting fogging!
I think that being closer to the Magnetic North Pole is giving you an "unfare advantage".:)

hrst
10-23-2009, 09:49 AM
Thanks for all this cheering and encouragement!

Living in Finland may also be a disadvantage. We are going to do the erythrosine-sensitized version soon, but in a month there will be nothing green left to test it with. Just snow; everything is black and white! Makes no difference whether your film is blue-sensitive, ortochromatic or panchromatic or even colour film! :D. And the day will be so short that we have to shoot everything at noon.

In fact, me and my family spend the summers in Northern Finland (where polar bears almost live, but not quite :D!) mining&washing gold; thus, I've got some gold I've mined by myself. We have dissolved it in aqua regia and will try to do gold sensitization with it :D.

Ray Rogers
10-23-2009, 12:10 PM
The blue objects in the lower left center are the two pump heads.
I hardly noticed the clothes pins :D but I did see some plastic connectors!
At least 2 types, (180 and 90 degrees)

Seems you use the 90 degree connectors for the supply vessels but not for the kettle.
Is that by design or just coincidence?

(Do you like them, any pro's or con's? Are they top-heavy?)

What are the 180 degree connectos for?

Ray