Hello,
Today we started making an emulsion for a first time. It's now standing in room temperature over this night, and tomorrow we'll proceed to noodle wash. If you don't mind, I'll post our process here just to make sure it's okay and maybe get some tips
.
First, I started by making silver nitrate. Silver should have been pure and nitric acid was 60% laboratory quality. I evaporated all the nitric acid, added distilled water and evaporated it. Still, it wasn't 100% white but a very little gray and smelled a little (some residual nitric acid?). I hope it's okay...
We followed the formula in PE's topic "A real formula", but made only 1/10 of it. We substituted 11,41 g of sodium bromide for 13,2 g of potassium bromide. We used food gelatin, not powder but "sheets". It doesn't say anything about additives but that it's made from pig skin.
We heated silver nitrate solution (B) to about 45-50 C and added ammonia. First it got yellow, and then completely clear. It took maybe about 5-20 ml of ammonia for 50 ml of B. (Didn't measure though.) Oh yeah, looking good at this point!
We heated A on hotplate magnetic stirrer to 45C and B to 45C in water bath.
We started adding B to A, about 5 ml at a time, every minute. It took 12 minutes to do this. B wasn't in water bath any more so the temperature dropped. But the hotplate stirrer has a sensor so it keeps the emulsion at 45C all the time.
After B was added, we kept emulsion at 45C for 30 minutes, keeping the stirrer going. Shut down the safelight for this time.
Then we poured emulsion to five 35 mm film containers. We left three of them to room temperature, about 25C, and two of them in refrigerator at about 10C. It takes some time to cool down, because we put the film containers in a plastic processing tank (because it's lighttight).
Tomorrow, we are going to add gelatin if necessary and noodelize some emulsion, wash (until wash water shows no crud when added some silver nitrate), and add gelatin. No sentisizers yet. Right?
And then coat some overhead projection transparencies (not the laser-ones but the cheapest ones, they are perfectly smooth like film base, I think they are acetate). We made a simple coating blade with about 10mil gap.
Now, is everything going well? At least it was very fun! Any tips & tricks for tomorrow?
I poured some emulsion on OHP transparency and dried it with hairdryer, then exposed to light and developed in paper developer. It got black! So it basically seems to work. But it needed much light.
I'll post results.
I've extracted some chlorophyll from leafs using acetone, we are going to experiment if it could be used as red sentisizer. But there will be so much to do before that point... If we can even get a decent blue-sensitive emulsion first!
PS. HUGE thanks to PE, your information about emulsion making here is priceless!! Thank you thank you thank you.
Today we started making an emulsion for a first time. It's now standing in room temperature over this night, and tomorrow we'll proceed to noodle wash. If you don't mind, I'll post our process here just to make sure it's okay and maybe get some tips
.First, I started by making silver nitrate. Silver should have been pure and nitric acid was 60% laboratory quality. I evaporated all the nitric acid, added distilled water and evaporated it. Still, it wasn't 100% white but a very little gray and smelled a little (some residual nitric acid?). I hope it's okay...
We followed the formula in PE's topic "A real formula", but made only 1/10 of it. We substituted 11,41 g of sodium bromide for 13,2 g of potassium bromide. We used food gelatin, not powder but "sheets". It doesn't say anything about additives but that it's made from pig skin.
We heated silver nitrate solution (B) to about 45-50 C and added ammonia. First it got yellow, and then completely clear. It took maybe about 5-20 ml of ammonia for 50 ml of B. (Didn't measure though.) Oh yeah, looking good at this point!
We heated A on hotplate magnetic stirrer to 45C and B to 45C in water bath.
We started adding B to A, about 5 ml at a time, every minute. It took 12 minutes to do this. B wasn't in water bath any more so the temperature dropped. But the hotplate stirrer has a sensor so it keeps the emulsion at 45C all the time.
After B was added, we kept emulsion at 45C for 30 minutes, keeping the stirrer going. Shut down the safelight for this time.
Then we poured emulsion to five 35 mm film containers. We left three of them to room temperature, about 25C, and two of them in refrigerator at about 10C. It takes some time to cool down, because we put the film containers in a plastic processing tank (because it's lighttight).
Tomorrow, we are going to add gelatin if necessary and noodelize some emulsion, wash (until wash water shows no crud when added some silver nitrate), and add gelatin. No sentisizers yet. Right?
And then coat some overhead projection transparencies (not the laser-ones but the cheapest ones, they are perfectly smooth like film base, I think they are acetate). We made a simple coating blade with about 10mil gap.
Now, is everything going well? At least it was very fun! Any tips & tricks for tomorrow?
I poured some emulsion on OHP transparency and dried it with hairdryer, then exposed to light and developed in paper developer. It got black! So it basically seems to work. But it needed much light.
I'll post results.
I've extracted some chlorophyll from leafs using acetone, we are going to experiment if it could be used as red sentisizer. But there will be so much to do before that point... If we can even get a decent blue-sensitive emulsion first!
PS. HUGE thanks to PE, your information about emulsion making here is priceless!! Thank you thank you thank you.
). We found out that it required about 13 g / 100 ml of food gelatin to become proper gel for noodeling and the final level was about 15-16 g / 100 ml to coat properly. That's quite a lot, isn't it. We had to heat and cool down the emulsion many times before we found this gelatin level, so maybe there is too much digestion now. The second batch went better, though, as we knew this high gelatin level.
