Another developing tank.

David M

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Everybody nowadays wants to design a new tank. This one looks remarkably easy to load. With rotary agitation it might not need much developer.

 
Looking at the design and the way the edges of the film are effectively against a wall rather like a groyne during rotary agitation the edges won't get even agitation, no issues with inversion agitation though.

Ian
 
The ad suggests emulsion out, but shows emulsion in!

I wouldn't expect the threads of the screw to hold the adapter to the tank core to last long.

Mike
 
It's curious the the picture shows the emulsion in, where it will be fully exposed to solutions. Perhaps the writer was a digital photographer.
I too had doubts about that screw. Do they intend that you pierce the centre column to make a permanent joint? Simpler to design the core as a duplicate of the centre feed tube, which could then be left out altogether.
I'm waiting for the next creative idea to surface. Clearly, film isn't dead.
 
Films not dead yet, it will be a slow process of supply and demand, creative ideas like this will sell and help keep the demand going,

Much like the mod holder, and looking at this design, I would not have confidence the film would leave home and stick to the tank sides, think I will stick with the sp45 for now, until there are real reviews of it in action
 
Unlike Ian, with inversion agitation I'd be concerned with the sheets slipping out of the holder; either one side or both.
 
Yes, just said that Alan forgot to mention with agitation, the times with the mod 54 the film had left home, off the holder and was stuck to the side of the tank, in fairness that was with the 1st version, the newer one was better, but just looking at this spiral does not instil confidence in doing that.
 
Unlike Ian, with inversion agitation I'd be concerned with the sheets slipping out of the holder; either one side or both.

I can't see how they'd slip out. I don't think it's an economic system unless you use replenished developer.

Ian
 
Or perhaps with high dilution and a long stand?
I don't think I'll get one myself, but I'll be interested if anyone does try it. It might be useful to anyone who has problems with dexterity.
 
I can't see how they'd slip out. I don't think it's an economic system unless you use replenished developer.

Ian

You might be right, but you've got...what...2 - 2.5cm of "wall" on each side and simple tension from the bowed sheet holding it in place? Based on my experience with 5x4 in a B's reel in a Paterson tank, and 5x4 in a Nikkor style stainless steel tank (both 1L of chemistry each), I can assure you that, based on sound, there seems to be quite a bit of turbulence inside those tanks with each inversion; and I invert slow and smooth.
 
Alan, I've used holder that use less tension for over 40 years and never an issues.

I can't see any other way of agitation other than Inversion with these reels, and it's usually reliable and effective.

Ian
 
Nice to see new stuff coming out , but ease of use , reliability both in use and how long it lasts will show how viable it is .
I keep being tempted to buy the SP445 for when I have just a few sheets to develop to save on chemicals rather than tray developing .
I tend to use my CombiPlan tanks , so easy to load and use . It's a shame they don't get brought back into production .
I find the Jobo real a right pain to load .
 
I keep being tempted to buy the SP445 for when I have just a few sheets to develop to save on chemicals rather than tray developing .

I have an SP-445 and it's an okay tank, but a few things to consider:

1) The film holders are not particularly easy to load (could just be me) or get back into the tank, once loaded with film.

2) It's a very narrow and tall tank which is easily tipped over.

3) It leaks, regardless of what Tim says using the "squeeze play."

4) Why do you think they're on V4 of their film holders?

I'll use this tank for something quick--testing, etc--but will not rely on it for final work. YMMV, of course.
 
I don't intend to get into a discussion about which tank is better etc etc but in the interests of balance I thought I might add my experiences with the SP-445 tank which I have had since just after they first came out - I ordered it from the States.

1) After a few dummy daylight runs loading the film holders and then loading them into the tank, my arthritic septuagenian fingers have had no problems with either process in the hundreds of times I have used them, but of course people have different levels of manual dexterity so that's probably not significant.

2) The first films I developed exhibited the characteristic marks caused by the moulding flash on the film retaining tabs but a few minutes vigorous re-profiling them with fine abrasive paper removed the problem and I have never had any marks since. I have to agree with others that this should not have been necessary in a properly QA'd product.

3) I have never had any liquid leaks using the "squeeze play" method that Alan refers to but I I use a tip given to me years ago when fitting anything which has an O-ring seal like the tank lid - moisten it before fitting. I simply wet a finger tip and run it around the ring before pressing the cap squarely into place. After doint the 'squeeze' the tank sides should remain indented, if not then there is a bad seal - repeat the process and try again. If it still doesn't work then either the O-ring is worn/damaged or the tank is distorted.

4) My film holders are the V2 ones I believe and I have never had any of the reported 'shadows' or other uneven development (although I can reproduce them fairly predictably simply by loading the sheets emulsion side in), however, the company is being responsible in that they have responded to customer complaints by producing different variants. As I understand it there had never been an 'acceptable' cause or reason why these 'shadows' have occurred so it remains to be seen if the latest 'textured' varient has any reported beneficial effect.

5) I use a two-axis looped inversion technique rather than just spinning it around it axis as shown in one of the instruction videos. I believe this ensures fairly active and efficient movement of the liquid in the tank.

6) Regarding the stability of the narrow base, what can I say is that I haven't had a problem, perhaps that is because between inversions I stand the tank between the stop and fix bottles in my tempered water bath.;)

So, for what it's worth, this is is my two pennyworth (or two cents worth for those across the pond), perhaps someone will glean something useful from it. :)
 
  1. The film holders are not particularly easy to load (could just be me) or get back into the tank, once loaded with film.
  2. It leaks, regardless of what Tim says using the "squeeze play."
I've found that leaking is usually the result of not doing up the caps sufficiently firmly, if you hear the air leak back in on letting go it's not sealed.
I've only had problems with loading the holders when I'd not got them quite dry from a previous batch (I don't remember why now but for some reason I needed to get two batches done in one evening).

Personally I prefer the SP445 to the Mod54, mainly because I don't quite trust the funnel on the modern Paterson tank (and the lid is fiddly which makes it for me the worst leaker of the set).
 
Keith, I didn't intend to start a "best tank discussion"...rather I was simply passing along my own experiences with this tank. I have worked on the clips with fine grade sandpaper, but I still get gouges on the film, occasionally. I will try the wet finger around the rubber o-ring trick; never done that before. I have the v1 and v3 holders, and, ironically, I have the most success with the v1 design. I finally gave up on the v3 holders because I could never predict when I'd get the dreaded "shadows" on my film. Honestly, I've never knocked the tank over, but it sure seems tipsy to me.
 
James, I can assure you that I screw the caps on tightly. I've never used the Mod54 so cannot comment. Actually, my favorite 5x4 processing tanks (in order of most fave to least) are: Jobo Expert Drum, homemade tanks for single sheet EMA development, Nikkor style stainless steel, B's reel in a Paterson 3-Reel System 4, SP-445. I, also, have 4-up hangers for tanks, but use those only occasionally for Pyrocat-HD minimal agitation.
 
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