8x10 Vertical Tank Development Issues

[Michael Kadillak]

If Kodak made the recommendation, it wasn't because of some self-serving marketing objective, but because it dramatically reduced the potential for user error. They will have likely tested every variable you can think of & several you can't to almost ludicrous levels of rigour. Other equipment manufacturers, specifically those who didn't collaborate with film manufacturer's R&D, seem to have had rather more lax standards. Kodak's data has a very significant safety margin built-in, so you might get away with some pretty serious departures from their recommendations & still be OK. That doesn't mean Kodak's claims are wrong. Rack-and-tank dip/dunk machines effectively deliver a lot more mechanical agitation than you seem to think, especially compared to a small deep tank system.

I did not make this statement off of the cuff. I worked in various capacities with Kodak in their manufacturing operations in Rochester New York and Windsor, Colorado for over 20 years. I also worked with their photographic staff for over 10 years. And yes, Kodak is fully capable of idiocy to preposterous levels. They did it all of the time. And in the interest of being brief I will not elaborate any of the long litany of examples along these lines. Kodak went bankrupt for a reason over a 25 year period. They did not feel the need to provide customer service or innovate to remain pertinent. The rest is history.

[Sam L]

I've put a lot of work into this over the past few weeks and I'm starting to get satisfactory results. Here's a photo taken today against a white canvas backdrop:



I ended up needing to do four major things:

1. I made a gas burst agitation system from my 1-gal tank
2. Increased the developer concentration from 1:250 to 1:100
3. Modified my Kodak hangers for double-sided film and gas burst agitation
4. Scanner upgrade

I'll create separate threads describing the interesting parts to share back what I've learned, but wanted to tie this thread up and say thanks for the recommendations. There is absolutely no way I would have gotten to this point without the help of this forum.

[j.e.simmons]

I’m interesting in knowing what modifications you made to the hangers.

[Tin Can]

My Gas Burst 7 years ago, still in use https://youtu.be/9DddOzSUeRc

Always fresh Rodinol 1-100 at 70F 7 to 10 minutes X-Ray

New CLEAN Kodak hangers 8X10, 5X7 2up and 4X5 4up

Small Air Compressor never N2

I got a lot of flack from many here

but I also got a lot of flack for X-RAY!

Rodinol is completely DEAD at 20 minutes

[Sam L]

Hanger modifications are cataloged here:

https://www.largeformatphotography.i...ded-X-Ray-film

[Sam L]

I tested 510 pyro and rodinal bracketed from 3-6 minutes 68F 1:100 on Fuji HR-U. 3 minutes was thin, 4:30 - 5:30 was about right, 6:00 was getting too dense. However, the 6:00 negative had the most even development.

I'm surprised your times are so much longer. It could be that by oxidizing the developer with compressed air you are seeing much longer dev times. I wanted to increase developer concentration to avoid local exhaustion and bromide drag but was worried about short development time. I will try compressed air instead of inert gas. Thanks for the idea.

Also nice to see the video of your super clean set up. Mine is quick and dirty. do you have a photo of your plenum?

[Tin Can]

My plenum looks DIY by somebody else

Very sloppy, small drilled holes in 3/16" SS tube, brazed to tank bottom and bent

One day I would like to make better

Seems to be ARKAY made as I have a catalog somewhere where it is pictured

and some Arkay was made in Michigan who also made the big sinks

Last I heard of him he was making dog washers

I use his 7' sink, had a 10' like new, sold it to a member

[Sam L]

At Tin Can's suggestion, I tried compressed air. It works!

I used Fuji HR-U x-ray film with 510 pyro at 1:100. The photo was normally exposed at ISO 80 using a sekonic light meter and 5600K LED studio lights. I bracketed the development time from 5 - 6:30 in 30 second intervals. I tried to match the gas pressure but this was approximate. It is possible/likely that I used more pressure with the compressed air.

In both cases, 5 minutes rendered a viable negative but with some chemical wash marks in the background. The wash marks disappeared by 6 minutes. 6:30 gave added density to the white background but evenness was about the same.

The only difference I can see is that the compressed air negative (right) has significantly more pyro stain than the inert gas negative (left):


Here's the photo at 6:30 development time:

[Michael Kadillak]

At Tin Can's suggestion, I tried compressed air. It works!

I used Fuji HR-U x-ray film with 510 pyro at 1:100. The photo was normally exposed at ISO 80 using a sekonic light meter and 5600K LED studio lights. I bracketed the development time from 5 - 6:30 in 30 second intervals. I tried to match the gas pressure but this was approximate. It is possible/likely that I used more pressure with the compressed air.

In both cases, 5 minutes rendered a viable negative but with some chemical wash marks in the background. The wash marks disappeared by 6 minutes. 6:30 gave added density to the white background but evenness was about the same.

The only difference I can see is that the compressed air negative (right) has significantly more pyro stain than the inert gas negative (left):


Here's the photo at 6:30 development time:

Hats off to your sheer persistence to finding out how to make your one gallon tanks work with this process. I took the easy route with 3.5 gallon Kodak standardized tanks and adherence to their technical recommendations without deviation after considerable angst from the Book of Pyro (only option is expensive customized tanks which I could not justify) and did not have to modify the sheet film hangers or tweak anything. The article I wrote for View Camera on this topic (May/June 2007) was the result of this long investigative process.

[Tin Can]

A lot of experts told me compressed air was beyond wrong

However as one shot developer, it does not matter

Nor does fixer

Good for you