I have only used the 400 version of Tri-X, as I know the 320 version is only on sheet films. I also know the 320 version is more typical for studio use. But how does the look of the two films differ, depending on subject matter? Is it only meant for studio flash use, or can it be used in natural lighting as well? What does it look like if used outdoors? My only other option is to use TMAX 400 which is available in 4x5 and 8x10.