Originally posted by Ben_Edict Pål, whatever you write is ofcourse correct. But in real world imaging, the rules need not be that strict. The hyperfocal distance for a 35mm lens at f/2 is just above 32m (on a K20), so simply turning the lens to its infinity stop, should be well within the DOF, even taking varying temperatures into account. With longer lenses, focusing is a harder act and one needs to invest more time and brains to get the best result - as you wrote.
Ben
My experience was not with the FA 35/2, a lens I've never used, but generally faster lenses (and a couple of slower ones; A 24/2.8 and A 35/2.8): the three FA Limiteds mainly. The Limiteds are designed to focus ever so little past infinity (to compensate for thermal expansion) so cranking them to they stop at the infinity mark won't necessarily give you optimum performance.
I also noticed that the precise infinity point on the lenses varied with temperature and camera bodies. I tried the camera in room temperature (kept indoors) and at minus 5 degree C. The LX was more prone to thermal variations than the MZ-S.
I found this a real hassle and almost alwas just stopped the lenses to F:4 for razor sharp images.....
Never tried aurora with digital but think I will the coming winter....