I use a 4x5 film holder very similar to this one. Mine was apparently made in the 70's by phototherm (according to the guy I bought it from). It is made of stainless steel and fits in a standard 4 roll stainless steel developing tank. It must not have been a very big seller because it is the only one I have ever seen. The concept is pretty much exactly the same as this one (3 sheets bowed out on each side) - but the execution is a bit different. Long story short, I am very happy with the results I am getting from the phototherm (my only gripe with it is loading - but the plastic one this guy is selling looks like it would be easier to load). I imagine that this fellow's contraption would offer similar results. In any case it is a very nice alternative to the leaky square tanks or the extremely overpriced 4x5 Nikors if you want to do some daylight developing of 4x5 film.
I bought one of these earlier this month (August). I was finally able to try it about a week ago and the results are outstanding. Since I already had a 3 reel Paterson, the ability to develop 4x5 in daylight without using a Yankee or other slosher tank was great. I never really had any luck with tray developing. Morgan O'Donovan's processing insert is a great advance in making 4x5 processing easier for the casual user.
Has anyone tried to use one of these in a Paterson tank for rotary processing?
“Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”
Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2
I have not, but I've thought about it pretty hard.
Originally Posted by MattKing
A few years ago I posted this: http://photo.net/large-format-photography-forum/00RMar
and this: http://www.apug.org/forums/forum37/5...tml#post710121
And when I first saw the eBay listing I sent the guy a message with the link saying I was very interested in his work.
The most likely issue I see with the current design is that as the unit turns in fluid it will generate a lot of drag on the edges, especially the corners. The Phototherm design compensates by having a support bar there, as well as the fact that the film curl on the Phototherm places the film in a better circle so that the leading edge acts in a more knife-like fashion rather than a hydroplane.
One issue Photohterm warns of with 120 film is that the rotating action of the processor can pull the film out of the grooves, so they have a little clip that holds the film tail in place. (Works great BTW.)
The Phototherm 4x5 adapter handles this with the plastic frame bar that holds the leading edge of the film as it turns in the fluid.
The current design on eBay - since it's not designed for rotary processing - doesn't take this into account. I expect that the film will come loose in the tank unless the rotation is pretty slow. I doubt it would take much more than two bands around the top and bottom edge to fix the problem (if it even is a problem), but that's more material and machining driving the cost up.
I approached Phototherm a few years ago about producing their adapters for the hobby market. While they were interested, the final decision was that it wasn't profitable. They even offered to rent the molds to me so I could produce them myself, but after crunching numbers I didn't pursue it either. A production run large enough to get the cost down to my target of < 20USD, so that they could be sold for 25USD was around 10K units. Smaller production runs cost more per unit, obviously.
Maybe the market has changed, and a higher production cost is feasible. And there's no harm in the fact that the guy on eBay has twice the volume capacity of the Phototherm unit. (6 sheets vs Phototherm's 4 sheets)
As far as his plan to a 5x7 unit, I've done quite a bit of measuring, and you can easily interleave 2 sheets of 5x7 into the same volume. As for 8x10, an adapter that's properly made could fit two sheets of 8x10 into a Paterson 5 reel tank. But by then you're talking about a lot of fluid to slosh around. But one made for a Phototherm could do 2 sheets of 8x10 in an SSK8 tank.
Last edited by michaelbsc; 09-01-2010 at 12:07 PM. Click to view previous post history.
Reason: language clarification; add link
Well Mike, I agree that loading this thing in a changing bag looks like it would be a real PITA. But for me, tank processing offers advantages in temperature control that I just find too difficult to maintain when working with open trays. The ambient temperature of my darkroom varies wildly as the seasons change. With open trays, so does the developer temperature. With tank processing, it's an easy thing to set the whole works into a tempering bath. I'm currently using an HP CombiPlan tank for 4x5 sheet film and I'm happy with it. For those who don't already have or for some reason don't like that tank, this device could offer an alternative. It should use about the same amount of chemistry as the HP, and while it is a bit more than you might need in an open tray, it is not terribly excessive.
Originally Posted by Mike Wilde
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I don't even think a changing bag is required. While I'm lucky enough (meaning old and gray-haired) to have a small permanent darkroom, even in my youth I just loaded in a closet. I'm sure there are some who can't do this. But don't let lack of a changing bag stop you. Finding a dark place isn't that difficult.
Originally Posted by Andrew_M
I have a changing bag, and if I need to do something while out and about it works. But I found the hall closet is dark, and far less confining.
I load my Patersons in the wine cellar. No windows, light tight. Just ordered one of these. Thanks for the link.
Originally Posted by michaelbsc
What we really need is a 5x7 one
Originally Posted by Ian Grant
Just load it sideways. It will be fine.
Originally Posted by L Gebhardt
Last edited by michaelbsc; 09-01-2010 at 05:46 PM. Click to view previous post history.
Did up a little video here as people were curious. No affiliation, just a curious Ebay buyer.
No report on consistency yet; I have only used it once so far and had good results. Time will prove whether it's consistent or not. I have plenty of experience with 35mm and 120 on the patterson reels, so this is a nice option. I also use the combiplan tank and tray developing.
Here it is in high def.