B’s Spiral.
I promised to write something about this new developing system for 5x4 film. The last of my doors is painted and drying, so at last I have time.
This spiral fits in a Paterson 3-reel tank. Although I do have some Paterson tanks, I discovered that I don’t have the right size, so I had to order one. This was a later model than my own, with a very wide mouth, so I had another few things to learn. I assume that any other three-reel tank would work, but I haven’t checked this.
B’s Spiral is 3-D printed and has the characteristic finely ridged surface. I was worried that these ridges might damage the film, but I’ve seen no scratches so far. The inside of the cavities seems a little smoother than the outside. It seems surprisingly light and in fact, it floats.
It’s white, for some reason. Why not black?
I did practice loading the film in the light and imagined that I’d mastered it, but in the dark, I struggled with the first sheet, until it dawned on me that, like loading film-holders, the film had to be exactly aligned with the opening, and I had much less trouble after that. No doubt practice will make perfect. Once aligned, the film slides in easily. It was easy, too, to check that each slot was filled by running a finger around the cut-outs, and there were no doubles. There are tiny ledges at the bottom of each slot, which work as non-obstructive backstops.
It’s essential to fit the tank’s centre column, both to stabilise the spiral and complete the light-trapping. The column is a close fit inside the spiral's core and the accompanying leaflet advises inserting it with care.
A litre of solution fills the Paterson tank and some of the solution is visible in the filling funnel. This surprised me, but it seemed to present no problem.
Inversion is surprisingly noisy, but I took that to mean that it was also thorough. As it was my first time using this tank, I inadvertently loosened the cap and splashed some solution onto the bench. Easily remedied by proper checking; it’s a mistake that should only be made once. Inversion didn't dislodge or move the sheets.
Apart from the spillage, the whole process was easy. Filling and emptying were fast and despite its width, the tank will empty directly into a cylinder mouth, without a funnel.
Washing is through the centre filling hole. I tend to fill and dump, but a continuous flow would work well too, although it might use more water. (We are all going to be more aware of water usage in the future.)
So far, no problems. Then I began to remove the film from the spiral. Surface tension made this quite difficult and I had to pull quite hard to get them out. Happily, there was no scratching. but one sheet had a faint half-moon thumb-mark at the top, where I was careless. All the other sheets were undamaged and unscratched. There may be a better way, which I’ll investigate next time. If there is a better way, I’ll write about it.
The films themselves were nicely and evenly developed and appeared as expected, the backing was properly cleared and any deficiencies had been hand-made by me.
In summary, if I can resolve my withdrawal difficulty, I’d recommend this device, particularly to anyone coming to LF from smaller formats and already having the necessary Paterson tank.