IMO use the ISO 400 for the 35mm setups. gives you the in the middle road between 200 and 800 speeds. the 800 will give you the best night picts but not very good daytime shots. on the other side of the spectrum, the 200 gives great daytime picts and okay night shots. hence the reason I split the advantages/disadvantages and used 400 when I used to run 35mm's.