if one were to use this as a street shooter, like josef koudelka, would iso 800 film be an acceptable compromise on the grain? i read a manual for the g617 online, the gx617 is outside my price range, and the large format lens does not appear to have a good depth of field at lower apertures. i've accepted this is a fair weather sunny f16 shooter. i would just use higher speed film for darker weather and accept the grain, if i were using handheld. my question: can depth of field be a problem close up? if so i would have to be decisive about when to take a shot.