mark - the problems with the Diana is that the Great Wall plastics company had such a poor quality control check, that nearly every Diana (and the 50 odd diana clones they produced) has a unique action and quirkyness - what turns out to be 1/100 on one Diana will turn out to be 1/74 on the next Anny --- an f11 value for one Traveller will be f8 on the next DianaF and so-on. Holgas arent much better ... this is why talking about exposure in such precise values is meaningless in toy camera photography. the best thing, IMO, is to pick a film - 400 iso's seem to be best for natural light - pick a developer (the more compensation the better) and find a time that works for you. Toycamera photography is an approach as much as anything - save the precise control for the hasselblads and rollies etc - toycameras=imprecision from exposure to print. much more freeing that way!