Dev tanks

David Rowland

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I have a couple of the HB combi plan dev tanks which work but I'm not particularly struck on as they take about 30 seconds to fill and empty. I've always been concerned about uneven development and to get around this when I empty the tank instead of removing the bottom plug I empty it through the top plug and invert it. Does anybody have a recommendation for a better tank eg the Stearman press ? of the things that go into Patterson tanks. your thoughts would be appreciated Dave
 
I use a couple of Jobo 2000 tanks, that both take a pair of 5x4 spirals. These are pre-rotary and need 1000ml per 6 sheets, while they take around 30 seconds to fill that has never been an issue in the 45 years I've been using them. It also takes the same time to fil with fixer (or stop bath/water) so it even s out.

I also have a Yankee tank, these are like the HP Combi tanks but don't have a sealable lid, I use mine for Quarter Plate and 9x12 sheet film as they are adjustable.

Ian
 
I've used Combo-Plan tanks for some time and filling and emptying time's never been a problem for me. I do use a pre-soak. It seems unlikely that it could remain in production for so long, in different continents, if it didn't work well. Drips might be a problem, but that seems to be common to all tanks and the Combi-Plan is no worse than others. I also modified an ordinary domestic funnel to fit onto the inlet spout to give a greater head and easier pouring. The supplied funnel is quite small, so it can be packed inside the tank.
I'm currently trying out a Jobo rotary tank. Not entirely happy with it.
I've also used a Yankee, but only twice. You agitate by shaking it back and forth. Messy. Might be useful for those low agitation processes which are so popular on this forum.
Then I got the Comb-Plan. It's out of production now so getting spares, particularly the rather fragile top clip, might be difficult. I seem to recall someone 3-D printing them at an exorbitant price.
The Stearman seems to be the tank du jour and it's rumoured that he's working on a six-sheet version.
 
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Thanks David And Ian as I said I've never had a problem it just doesn't seem quite right. I did pick up a few of the top clips from somewhere a few years ago so I have some spares and as with the way of these things as soon as you buy spares the originals never break. The Stearman appeals as it only needs just under half a litre of chemistry. Thanks Dave
 
The Stearman is the tank I use, the 475mL of chemistry for four sheets being the deciding factor for me. There are only two things I dislike about this tank, the first is that it takes time to develop the knack to stopping it leaking and the second is it is hideously expensive for what it is.
 
I use the Paterson system 4, 1 litre tank with either a MOD54 or a 20th Century Cameras reel. Far prefer the 20th Century reel, unfortunately still no UK distributor and postage and vat from either the US or EU are ridiculous.

If a few were interested in going in on one shipment that may save a bit and make it worth doing?
 
I also use a Stearman, despite never having developed 4x5 sheet film before last January, I have never had a problem with it. It does leak a wee bit, but so does my old Paterson tank, it is quite expensive at £108 though.
 
I have a couple of the HB combi plan dev tanks


With having a couple of them you could build a development street - fill in the chemicals separately to each tank and then dip the negatives from one liquid to the other.
 
I use open tanks with film clip hangers. Depending on how many sheets I have, I either use 1/2 gal Kodak Rubber tanks or 1 gal Tupperware brand plastic tanks. For "stop bath" I have one of the 1gal tanks fitted with a hose barb at the bottom connected to a hose from the tap. This is to allow water to flow from top to bottom and overflow into the sink to remove residual developer.
 
You need to be using a lot of sheet film or other films to justify using deep tanks and when you do it needs to be done properly.

Also don't use tap water if you want good fine grain unless you regulate the temperature carefully, you need to keep all baths including washing within +/- 1ºC. I'd take anything said above as poor practice, and results show this.

Ian
 
You need to be using a lot of sheet film or other films to justify using deep tanks and when you do it needs to be done properly.

Also don't use tap water if you want good fine grain unless you regulate the temperature carefully, you need to keep all baths including washing within +/- 1ºC. I'd take anything said above as poor practice, and results show this.

Ian

Much like my running water stop bath, your wisdom continues to overflow ...

> Also don't use tap water if you want good fine grain

That's both imaginary chemistry and absurd on its face. Grain is a function of the film structure and the developer (and, in the extreme, temperature). Distilled water is valuable as a way to eliminate variability, not grain. Kodak, Ilford et al long ago formulated their developers and films on the assumption of people using ordinary tap water. Using distilled (which I do without fail for developer, fixer, and toner) merely provides consistency, not grain reduction. (I will stipulate that if you have really bad/strange water, it could, affect grain. But this is an edge condition and not the norm that Kodak and others used as their guide. In fact, they never even recommend distilled water in their mixing instructions.)

> ou need to keep all baths including washing within +/- 1ºC

That's easily enough done in my darkroom but it's questionable whether that tight a control is needed for monochrome. There was this very long winded stuff that came out some years ago about microreticulation but it was about as valuable as the Beyond The Zone System bunch who thought 0.1 f/stop matching was useful. It is certainly true that avoiding wide temperature swings is important to avoid actual visible reticulation, hence I keep everything within about 2 degrees F. What is far more important is to not work too hot. 20C is a pretty good target temperature. If we work a lot hotter than this, we risk very soft emulsions, scratching and other surface damage. I am fortunate that my darkroom quiesces at 20C +- a couple degrees year around and water temp is easily matched to this.

> I'd take anything said above as poor practice, and results show this.

We continue to wait with great anticipation for you to unveil your standard-setting images that put me (and all the rest of us) to shame. I've investigated the stuff you've made available on line and - outside your commercial work, which is quite workman like - it's ... how can I say this politely ... unremarkable to the point of bland - well, at least to me. One man's bland is another man's Carravagio.

You see, I have said all along that we all see things differently, so it's awful hard to call out someone else's work because you don't see the same things the same way. But this hasn't deterred you in the slightest has it? So far, you've been long and loud on critique, but missing-in-action when it comes to actually showing us these better images you make. As always, I welcome learning from my betters, so do please show us that "better" standard to which you hew ... I cannot wait.

In the mean time, keep stomping on beginner images and telling well intentioned and earnest beginners that their images aren't sharp or that they have too much sky. Nothing like some old grouch to take all the fun out of it...
 
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John Davies gets quite remarkable detail from his 120 negs. I’ve seen him develop film at a workshop. Unremarkable developer - D76 or ID11, I think - but he was very, very, very picky about temperature.
(My own tap water temperature can fluctuate quite a lot. The house has long pipe runs and the hot and cold pipes are close and parallel in places. I guess that all old-ish houses will be much the same. The darkroom temperature fluctuates widely too.)

I’m not at all sure how perfectly drinkable domestic water affects sharpness as such. Some other regions and nations may have a problem.

Might we agree that many aspects of quality are subjective and apply the de gustibus rule?
 
John Davies gets quite remarkable detail from his 120 negs. I’ve seen him develop film at a workshop. Unremarkable developer - D76 or ID11, I think - but he was very, very, very picky about temperature.
(My own tap water temperature can fluctuate quite a lot. The house has long pipe runs and the hot and cold pipes are close and parallel in places. I guess that all old-ish houses will be much the same. The darkroom temperature fluctuates widely too.)

I’m not at all sure how perfectly drinkable domestic water affects sharpness as such. Some other regions and nations may have a problem.

Might we agree that many aspects of quality are subjective and apply the de gustibus rule?

In general, I affirm any process which get people the results they want. What I do not buy is that everyone must do things in precisely the same way, see things exactly the same way, and stick to a book of immutable artistic rules.

That said, the counterargument for the "you must maintain temp within a trillionth of a degree" bunch is the vast body of photographic genius that has produced a rich canon of work without doing so. Weston notoriously made thin negatives - and amazing prints. Strand's negatives were spectacularly dense - and made amazing prints. Rinse, repeat the other masters like Adams, Atget, Brassai and so forth. I am really sure they did not have their darkrooms tuned to 1 degree C but somehow they managed. I've actually seen Weston's darkroom when it went on display at the Boston MFA. It was incredibly simple and unassuming.

Whether or not microreticulation is a sufficient factor as to drive such demand for tight temp control is almost irrelevant when you consider that people more usually show their work on monitors over the web - where such fine detail is lost almost by definition. I have stuff that is tack sharp but by the time I scan the print and publish it on the web, at high magnification it looks less so. I could partly solve for this by either manipulating the scan to make it sharper or just publishing a scan of the negative itself. But that's not how I work and kind of think of either of those as cheating. Here, for example, is such an image shot on 6x9 sheet film:


Ctein wrote well on how we perceive sharpness and it has as much to do (or more) with image size and viewing distance as it does film development minutae.

Methinks this is asking for 4 digit precision from 2 digit data, but hey, if it works for others, more power to them.

P.S. It is worth noting that when I researched the time/temp tables when I was building the compensating timer I've mentioned before, I discovered general agreement about the general shapes of those curves but the published data didn't remotely resolve down to 1 degree C. So at least for purposes of dev time, it's not that fussy. So much so that I used a single correction curve for film development, irrespective of the film-dev combo. The published data showed that it just didn't matter all that much. Although I only researched Kodak films, both published data from Kodak and Ilford as well as formula-based corrections showed common insensitivity to small changes in temp. I could have expanded it to other film manufacturers but the published times for the major products are similar enough that I didn't bother. The timer thus doesn't bother to measure or correct for variations smaller than 1 degree F and it does so with a single set of correction factors for all film/dev combons, and another single set of correction factors for all papers.

If anyone cares, the actual calculation of correction factors I used - and comparisons made from different sources - can be found here:

 
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Ctein used a 1920s technique, he wet mounted his negatives, I've read his book and to be frank it was not worth buying.

John Davies noted some years ago that his students using the same film FP4 and the same developer ID-11 were getting quite different results when it came e t grain. The difference was temperature control and what an eye opener.

Ian
 
Reticulation, micro or not, is not produced by temperature itself, but by rapid changes in temperature, and I understand that sudden changes in pH can have the same effect.
Experienced and prolific photographers, like Strand and Weston will almost unconsciously have come to produce negatives that suit their own proclivities. I don’t know about Strand, but Weston developed by inspection, so he must have got the density he wanted.
I should add that when I saw some actual Strand prints, I was disappointed. Not so with Weston.
Photographers, perhaps like ourselves, often deviate from manufacturers instructions, but those instructions are written so that the Man on the Clapham Omnibus can produce acceptable results, probably while photographing his family on Clapham Common. To achieve this a good deal of slack has to be built into the process.
Other processes, like the vanished dye-transfer demanded more precision.
I did have a friend who produced very precise negatives, because measuring their density was part of a research project. This was confidential, so he never explained further. He did devise a method of applying developer to a negative almost instantly, using a vacuum.

One of the attractive features of film photography is the degree to which it is flexible at every stage, from choice of material onwards. Consequently a wide variety of results can be produced by a wide variety of methods. It can even accommodate messianic densitometry.
 
Reticulation, micro or not, is not produced by temperature itself, but by rapid changes in temperature, and I understand that sudden changes in pH can have the same effect.

Exactly - well, within reason as very high or low temps cause other undesirable artefacts. I am blessed with a darkroom that sits
consistently at right near 68F within a degree or two. That means all my mixed chemistry and water used to make one shot
developer are similarly at this same temperature. All I have to do is match the running water stop bath to that temp.

One of the attractive features of film photography is the degree to which it is flexible at every stage, from choice of material onwards. Consequently a wide variety of results can be produced by a wide variety of methods. It can even accommodate messianic densitometry.

Having done oodles of denisometric testing, I can say with some confidence, it ain't messianic. It's painful, time consuming, and distracts from making real images.

It was useful in the beginning to prove that the old rules of thumb were pretty reasonable starting points for conventional development: Expose at 1/2 box ASA, underdevelop 20%. N+- can be approximated to a first degree by adding/decreasing development time from that rule by 20% per N moved, and increasing- or decreasing ASA 1/3 stop for each step. It's not perfect but certainly close enough to get going. After than, one can inch up on the actual corrections with each iteration of results.

In truth, most mechanical leaf shutters can vary by 1/3 stop or more from nominal, even when very well adjusted, and far more than this if they are elderly, as LF shutters tend to be. So, unless you're carrying around the correction data for every shutter speed on every different shutter, you're likely to encounter far more variability than very fiddly density testing would seem to provide. The good news is that old shutters tend to be slow which thus give you more exposure. Except in the extreme, this is usually OK.

Densitometry was useful to help me better understand the H/D curve, but after the first dozen or so film/dev combos tested, having seen essentially consistent results across the board that fit in the aforementioned rule-of-thumb, I ceased doing density measurements. This was all the more the case when I switched to Pyro-based staining developers as my sad little densitometer has no way to correct for the stain.
 
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I wasn’t labelling you as a messianic densitometrist.
There is another LF forum. It harbours people who are endlessly fascinated by hitting that exact Holy Grail point of 0.01 over B+F. I believe that I’ve read of someone making a chart of shutter speed corrections, too.
Naturally, I wish them well. It’s always possible that the work they do requires these very high levels of accuracy. I don’t read them now my curiosity is sated.
[As an aside, Leica used to scratch the exact, tested focal length on their lenses. Some scientific applications apparently need this.]
It seems to me that the Zone System was conceived as a rough-and-ready field guide to exposure and development. This accords well with what I shall call (for brevity) the rough and ready Real World. Very few scenes take any trouble at all over a third decimal place. Other systems of exposure have worked well in the past. Atget seems to have managed quite well. He too developed by inspection.
I recently rediscovered my Johnson’s Exposure calculator - a circular slide rule that gave good results even with Kodachrome.
Once upon a time, photographers used extensive tables for exposure. One of them, used in the industrial Midlands, included wind direction. This was because when the wind came from the moors, it was clean, but from the other direction it was laden with sulphurous yellow smoke, which substantially affected exposure on blue-sensitive plates.
 
I also use Spearman tank. Easy and quick to load 4 film sheets, no scratches. It leaks sometimes a bit but surprisingly no light leaks. Never experienced uneven development.
 
They advise you to squeeze the tank gently as you close the spouts. It also helps if you are careful not to overfill it, as there’s not much headroom.
It would have been nice if it took an actual 500ml, but it’s apparently sized for the old British Imperial system. The last remnant of Empire is lurking in your darkroom.
 
They advise you to squeeze the tank gently as you close the spouts. It also helps if you are careful not to overfill it, as there’s not much headroom.

Yes, that's what I do but it leaks anyway. But not a big deal.

It would have been nice if it took an actual 500ml, but it’s apparently sized for the old British Imperial system. The last remnant of Empire is lurking in your darkroom.


:D
 
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