My point was not to compare the cost of 35/120 against 4x5 but to compate the cost of color to black and white in the same format. The roll film costs per frame are fairly flat but the costs per frame in sheet film spike way up for color.

Basically, if a roll of T-max costs $8 and a roll of Porta costs $9, why does a sheet of T-max cost $2.50 but a sheet of Porta costs $5 which is twice as much?