Wish I had sme more exact data - but I can tell you this much: I have done some night shooting with 400 film using this method - and I am still alittle hit and miss but the ones that did come out, were wonderful. For night time I set shutter at 1 or 2 seconds, apperture at 16 or 22 (I did have some street lights, etc) and then flashed my Sunpak manually from where I wanted the light to come from - as soon as I heard the shutter open or saw the flashing light go off on the timer. I understand you will have to adjust a bit - I found my ability with light meters and the ability of the meters available to me rendered the instruments useless, so I arrived at these values by trial and error. Got some wonderrful results and had some flexibility with the flash since I could run around with it in hand - you may have to have an actual mechanical/electric synch since I doubt anything over 1/4 sec would be applicable.