Do rotary processors affect how the film looks in the end? (tonality, film speed / shadow detail, etc.)

[dcy]

You can even run into problems with uneven development when you use inversion agitation, if you always agitate in a very constrained, exactly duplicated way.

Ugh... That's me. I was aiming for consistency.

For that reason I always tell people who are new to this to both invert and rotate the development tanks - you want the developer to tumble ang cavitate through the film. You should be able to hear it gurgle.
It is possible to achieve good results with a less energetic approach, but it takes a lot of attention and care toward adding a reasonable amount of chaos.

Understood. Shake it like you're making a margarita!

EDIT: Kidding aside. What I normally do is I rotate the tank along one axis when turning it upside down, and then along a perpendicular axis when turning it right-side up. No idea if this provides sufficient randomness, but perhaps it's close enough to the tumbling you describe.

 

[DREW WILEY]

Leave making liquids frosty or frothy to Dairy Queen and the rabies virus. Too much agitation leads to foaming, bubble marks, and surge marks. Find a happy medium.

 

[GregY]

Ugh... That's me. I was aiming for consistency.



Understood. Shake it like you're making a margarita!

EDIT: Kidding aside. What I normally do is I rotate the tank along one axis when turning it upside down, and then along a perpendicular axis when turning it right-side up. No idea if this provides sufficient randomness, but perhaps it's close enough to the tumbling you describe.

I use a figure 8 motion, but i agitate gently the 'margarita' only got me increased contrast that i don't need.

 

[dcy]

The problem that @mshchem refers to is that of laminar flow, which can be summarized/simplified as a liquid flowing relatively slowly across a surface, with the liquid forming more or less discrete 'layers' that don't mix (much).

It's always fun when I get to think about Reynolds numbers outside my day job.

 

[mshchem]

Never thought of processing paper on a tube. I might give it a try. --- Still not gonna buy a Jobo, but as @GregY said, you can just roll the tube on the counter.

At this point I've got the cost of chemicals for the darkroom to a level that I'm comfortable, but if I can lower that cost a bit more without a huge hassle, why not. Problem is, of course, you can't see the image on the paper appear, so you can't make a spontaneous decision to shorten or lengthen development.

I've got some stainless steel Premier drums for processing color prints. From the early 1970's. The drum "tube" has a light trap in one end. You insert the paper into the drum in the dark, then you'd float the drum in a 100°F water bath (Kodak CP-5 chemistry) then stand and spin the floating drum for the roughly 7 minutes and 5 different chemicals to make a print.

 

[dcy]

As I recall it from 1st year Physics so long ago, the study of thermodynamics and fluid flows was a far from simple exploration!

"Aristotle said a bunch of stuff that was wrong. Galileo and Newton fixed things up. Then Einstein broke everything again. Now, we’ve basically got it all worked out, except for small stuff, big stuff, hot stuff, cold stuff, fast stuff, heavy stuff, dark stuff, turbulence, and the concept of time”

-- Zach Weinersmith


Hydrodynamics is a big part of my day job (astronomer) and I sure don't find it simple.

 

[MattKing]

If you want a good, repeatable way to add appropriate amount of chaos to your agitation, try this:
1)hold the developing tank vertically, with your palms - one hand on the bottom, and one hand on the top;
2) turn the tank upside down in one direction - e.g. clockwise - by rotating your hands and wrists, so the bottom hand ends up on the top and the top hand ends up on the bottom - note how the natural action of your wrists imparts both inversion and rotation to the tank;
3) repeat in reverse what you just did in order to move the hands back to their original position, again imparting both inversion and rotation;
4) do the same again, except start out in the opposite direction - counter-clockwise instead of clockwise; and finally
5) return the tank to vertical.
In total, that is two inversions. To someone watching you, it will look like you were driving a car/steering.
It is far harder to describe than it is to do it.
It is a good idea to wear gloves - perhaps a darkroom apron too.

 

[MattKing]

Never thought of processing paper on a tube. I might give it a try.

In combination with one of the Beseler or Unicolor or similar rotary agitator, it is a really good option for those of us who need to rely on temporary darkroom space.
I'm particularly fond of the old Cibachrome tubes.

 

[xkaes]

Problem is, of course, you can't see the image on the paper appear, so you can't make a spontaneous decision to shorten or lengthen development.

You may consider it a problem. I consider it a blessing. It forces me to get the exposure correct -- which I should always do. The processing time is determined to achieve maximum black -- EZ to determine with a simple test -- not that every print will have a maximum black, but if you don't print to the minimum time that achieves maximum black you'll never get it in a print that benefits from it.

Another BIG benefit from tubes is you save a LOT of space vs trays -- and I won't mention the joy of moving trays full of chemicals. OOPS, I just did.

 

[MattKing]

When I use tubes, I standardize on a development time toward the long end of the recommended range.

 

[Bill Burk]

From the link: "One gentle flip per minute is optimal for B&W." I wonder what the author's stand is with stand development. Sounds like someone found the best way for themself and believes in it.

I tray-developed for a couple decades, and still do for 11x14. For the last couple of decades or so, everything smaller than 11x14 goes into Jobo Expert Drums and rotated at 15 rpm...that's how fast my Unicolor motor base can go. I contact print in alt processes with no burning/dodging...so any uneveness in processing would be undesirable. So far so good. But I am always expanding the DR of the film, which probably uses the advantages of the continous agitation (instead of continous agitation fighting attempts to contract the DR).

Palms, Spring, Death Valley, 8x10 pt/pd print.

I can't believe you use Unicolor roller with Expert drums but makes sense. It would "work". I threw mine out when I couldn't get Cibachrome anymore.

 

[Bill Burk]

Look at your negatives critically for evenness of development.

I'm a fan of Kodak agitation. But I have to admit I get uneven processing. Kodak agitation in a small tank to me means: Continuous agitation for the first 45 seconds, then about 5 seconds agitation every 30 seconds thereafter with a few hard raps down on the butcher block before putting the tank back in the water tempering bath for the next "almost" thirty seconds. I feel sorry for my neighbors when I develop film because I make so much noise.

What I see lately is the center of the reel and outer reaches near the end get "different" development than each other.

The sides nearest sprocket holes get "a little more" development than the rest of the 35mm frame.

When I develop 4x5 in tray, the edges also get "a little more" development than the rest of the frame. In a tray, I use continual shuffling six or seven sheets. The top sheet gets fresh developer about once a minute, then has to get by with the laminar layer for the rest of the time as the sheet on top of it smothers.

 

[Paul Howell]

Never thought of processing paper on a tube. I might give it a try. --- Still not gonna buy a Jobo, but as @GregY said, you can just roll the tube on the counter.

At this point I've got the cost of chemicals for the darkroom to a level that I'm comfortable, but if I can lower that cost a bit more without a huge hassle, why not. Problem is, of course, you can't see the image on the paper appear, so you can't make a spontaneous decision to shorten or lengthen development.

As I have motor base and tubes I have used drums for black and white, currently I am using trays, but, drums use a bit less chemistry but I could mix up just enough chemistry for a a couple of 8X10s. I've used Clayton and other liquid concentrates, with Clayton the recommended dilution is 1:9, I would mix 1/2 oz concentrate with 4 1/2 water for working per 8X10. Standard stop and fix, a bit less than developer 3 oz all dumped, 8 water rinse, followed by 3 oz Perma wash then remove and wash in a tray or print washer. For larger printing session having to wash the drums between prints is just too much a hassle so I revert to trays. I also like watching the print come up in the developer.

 

[Vaughn]

I can't believe you use Unicolor roller with Expert drums but makes sense. It would "work". I threw mine out when I couldn't get Cibachrome anymore.

The noise they make can get quite horrendous after awhile. I have a Beseler motor base that also rocks the tubes as they spin, but have not tired it yet. The Drums can want to walk off the motor base sometimes, so one can counter that. I do not feel very comfortable leaving them long while turning without adult supervision.

Before the Drums I tray developed and prolonged the agony by doing them one at a time...although I eventually used two developing trays in a larger tray and just agitate the larger tray.

I have three 3005 drums -- during workshops I can load up all three (15 sheets of 8x10) and process one drum at a time (pre-soak, Dev, stop, fix, partial wash), then start a new drum while finishing washing the first batch. Goes pretty smoothly.

 

[mshchem]

If you want a good, repeatable way to add appropriate amount of chaos to your agitation, try this:
1)hold the developing tank vertically, with your palms - one hand on the bottom, and one hand on the top;
2) turn the tank upside down in one direction - e.g. clockwise - by rotating your hands and wrists, so the bottom hand ends up on the top and the top hand ends up on the bottom - note how the natural action of your wrists imparts both inversion and rotation to the tank;
3) repeat in reverse what you just did in order to move the hands back to their original position, again imparting both inversion and rotation;
4) do the same again, except start out in the opposite direction - counter-clockwise instead of clockwise; and finally
5) return the tank to vertical.
In total, that is two inversions. To someone watching you, it will look like you were driving a car/steering.
It is far harder to describe than it is to do it.
It is a good idea to wear gloves - perhaps a darkroom apron too.

Perfect agitation technique. I was taught this when I attended a demonstration back in the last millenia c 1975. Somewhere I have a pamphlet titled "Agitated About Agitation?" by the H&W Control guys. First time I saw what a technical pan type film and appropriate developer could do. These guys were showing 16x20 prints from 35mm negatives. Amazing!

 

[mshchem]

The noise they make can get quite horrendous after awhile. I have a Beseler motor base that also rocks the tubes as they spin, but have not tired it yet. The Drums can want to walk off the motor base sometimes, so one can counter that. I do not feel very comfortable leaving them long while turning without adult supervision.

Before the Drums I tray developed and prolonged the agony by doing them one at a time...although I eventually used two developing trays in a larger tray and just agitate the larger tray.

I have three 3005 drums -- during workshops I can load up all three (15 sheets of 8x10) and process one drum at a time (pre-soak, Dev, stop, fix, partial wash), then start a new drum while finishing washing the first batch. Goes pretty smoothly.

I processed 8x10 fiber base prints a couple times using the 3005 drum no troubles. Not sure if I got lucky or if it would always work. RC would definitely work.

 

[mshchem]

When I use tubes, I standardize on a development time toward the long end of the recommended range.

I picked up a Zone VI compensating timer and always develop to the same time, usually 2 minutes at 20°C as that's mostly the temperature in my darkroom. I use a little heater in the winter. Not developing prints long enough is a problem. 3 minutes is a good standard if one is patient.