Originally Posted by ReallyBigCameras
I have tried gaseous burst agitation with 8x20 in a test tank that Alistair Inglis built when I was assisting him with this process for a number of ULF formats.
I can tell you that it works marvelously well but the logistical issues with ULF do come into play in this instance as they do with lenses, holders, film etc. Not impossible, it just is what it is.
Even skinny tanks to accept such large sheets of film amount to quite large volumes of chemistry. Alistair can in fact produce gaseous burst agitation tanks and hangers for a number of ULF sizes including 14x17, but the prices are commensurate with the time and effort in fabricating these products. You can see these on his web site. You also need N2, a solenoid valve and a timer to control the bursts.
Gaseous burst agitation is optimal when you can acquire used tanks, plenums and the other accessories. For 35mm, 120/220, 4x5, 5x7 and 8x10 the process is truly foolproof. Beyond 8x10 it is surely possible, but it is a road much less traveled.