Shot with an M6 TTL w/ Zeiss 35/2.8 C Biogon, on Tri-X 400 at 320. The sequence is the same for all shots: no filter, (G), 040. Based on these results I would probably go with the (G) over the 040 as it provides virtually the same overall effect but costs ~2/3 of a stop less light (which also makes it easier to shoot through an SLR), though that could be useful on extremely bright days with a camera that only goes to 1/1000. Resized to 25% of the original scan size.