Peter Alling wrote: "Even if noise was effectively the same at ISO 100 and 200 having the lower speed would allow more DOF control in bright light without using ND filters, (which can be a PITA)."
Point well taken, Peter. Currently my outdoor film is Fujicolor NPS 160. I chose it because it has been nicknamed "Reala 160." It has the same film grain index and resolving power as Reala 100. So I figured I'd be getting something for nothing. Well, my outdoor camera's faster shutter speed is 1/1000 second, and there are times when a 100-speed film would give me the flexibility to shoot at wide apertures. I generally have two bodies on hand: One with 160, the other with 800 and flash. I used to set the 800 body at 1250 and push process, using a third body with 400 film as my flash camera. But I shoot a lot of wide angle flash (20mm), and with a diffuser in place, 400 film lacked the reach. Plus, with 800 film, the flash doesn't' produce as many white-faced close-ups. Paul Franklin Stregevsky