nitrogen burst development tank (building your own)

[jrshupper]

So...can a system be built using compressed air?

John

[BetterSense]

I'm not sure it would be any cheaper to use high pressure air like a scuba tank. Using regular 100psiish air would work fine with one-shot developers.

My major question is what does the bursting. The name "Nitrogen burst" sounds like the bubbles don't run continuously but in bursts. Do you manually yank open a ball valve and close it real fast or what? Use an electric solenoid valve?

[Michael Kadillak]

I continue to be amazed at the propensity of people in the LF/ULF community to ignore years of proven research when it comes to subjects such as this. Usually the incentive is to cut costs. For over 30 years through today gaseous burst was the state of the art for attaining professional processing results and there are a number of technical reasons that an inert gas was chosen for this task.

I wrote an article a while back in View Camera on this subject and included some technical information from Kodak in it. In this article I disprove the conclusion by Gordon Hutchings in his Book Of Pyro that you need custom tanks and hangers to use N2 burst with pyro developers. Nothing could be further from fact. You can use regular tanks and plenums along with regular Kodak 4A hangers and get absolutely perfect results with pyro developers WITHOUT all of that expensive custom tank and hangers stuff.

If you feel a need to tinker, I would suggest your time would be better spend to tinker with various developers, film and printing papers. Take advantage of the extensive research that has been completed relative to gaseous burst development and utilize it. It will save you considerable time and frustration.

[BetterSense]

I think the bottleneck is that hobbyists, like myself, don't have access to all those "years of research".

[Michael Kadillak]

Send me your direct e-mail address and I will give you all you want to know on the this subject. You can PM me. I regularly support ALL analog shooters in every way that I can.

Best, MK

[iozone]

Michael is right. If you are patient you can find anything you need on ebay. Here is a tank, rack, hangers and plenum on fleabay for $50.00 - Item number: 190463886054
I have seen nitrogen burst timers with solenoid new for about the same price.

Regarding the cost of nitrogen, once you have a tank and regulator the nitrogen itself doesn't cost enough to matter.

This is a GREAT way to work.

I have the same pubs that Michael has (provided by him) I'd also be happy to forward them to anyone who might be interested. Just PM

[Brian K]

Why would someone use nitrogen burst with a one shot developer? Who mixes 3 1/2 gallons of developer for a one shot process? The normal usage of developers with nitro burst is to use replenishable developers. And you don't want to use regular air with that because you will oxidize it faster. The cost of the nitrogen was pretty low and the results were superb.

[jrshupper]

I actually was thinking of building a small tank NB development system that would use much less than 3 gallons--more like 1 liter, for smaller batches. I have access to scuba tanks and could modify a regulator/solenoid combo to use air.

John

[Michael Kadillak]

I actually was thinking of building a small tank NB development system that would use much less than 3 gallons--more like 1 liter, for smaller batches. I have access to scuba tanks and could modify a regulator/solenoid combo to use air.

John

If you have the time and the inclination to do so, by all means go ahead. After about the sixth iteration of producing horrific negatives myself none of which I could point to a semblance of forward progress I was forced to abandon my Thomas Edison tendencies. I realized that my objective was to produce quality prints. The processing of negatives is an intermediary step. My frustration caused me to back up the truck and that is when I found the Kodak technical materials that were the result of years of technical research on the subject of N2 gaseous burst and only then did it all come together.

I sincerely want to encourage you to continue to use sheet film because we are all in this together. My comments above are not in any way pointed or demeaning. I just do not want you to get excessively frustrated. Alistair Inglis knows acrylic like nobody else and he is one of us. He produces what you are looking for. I will also tell you that you can use your compressed air for the stop and fix cycles but it is problematic for sheet film development for the obvious reasons.

Cheers!

[BetterSense]

I'm thinking about doing this for 4x5 in a Kodak hard rubber tank, capacity ~1.75L. Not sure if there's enough space at the top and bottom though, based on what Kodak recommends.