I'm with Michael and Sandy on this one. I also find six holders to be my magic number in ULF. I hate reloading in the field. So, even though I have yet to burn through all 12 sheets in a single day, it's nice to have some loaded holders ready to go the next morning.
Originally Posted by Michael Kadillak
Depending on how you process your film, 12 is also conveniently divisible by 2, 3, 4 and 6. So, if you process in trays, drums or hangers, 12 sheets of film seems to always divide evenly without an odd sheet or two left over waiting for the next batch of film to process. Of course, that's not always the case, but it seems to wok out nicely for me more often than not.
So, in 7x17, I have six walnut AWB holders. In 14x17, I have six Fidelity holders (and I don't even have the camera completed yet). In 7x17 I usually carry three holders with me if I'm hiking any distance from the vehicle and leave the other three in the car for later. Of course, if I'm working near the car, I just grab what I need when I need it.
In smaller formats, I have a lot more holders. I have more than fifty 4x5 holders. When I was shooting 4x5 in high volume, but hadn't yet switched to Quick/Readyloads, I liked to load up 100 sheets (two 50 sheet boxes) of Velvia before leaving for a week long trip. In 4x5, if the conditions were right, I usually averaged exposing about 20 sheets of film a day. Sometimes a little more, sometimes less. By starting the week with 100 loaded sheets, I had to reload only once mid-trip.
In 4x10, I have 15 holders. That also seems to work well for me.
In 8x10, I have 25 holders, but rarely seem to need them all. The only reason I have so many is that I got a really good deal on a case (twenty) of unused Fidelity 8x10 holders a couple years ago. I could get by with less, but when it comes to holders, I'd rather have too many than not enough.