<<< But, in fact, the claim of "no cropping" is an irrelevancy. So long as the two photos were really made on the same size film and enlarged the same amount, and so long as they show the points we need to measure (which they do), then cropping stuff off around the edges makes no difference. >>> Well, it's pretty good evidence to me that they lied ;o) It's not an irrelavancy in the question as written because 1) they didn't mention enlargement 2) the images were presented at equal size (on my monitor anyway) I suspect they said "no cropping" because, unlike many modern digital camera users, film users realise that cropping a neg/print does not change the focal length of a lens. They said "no cropping" to remove the possibility that the two images were shown at different magnification: they srewed up because the format they showed was not that they claimed. They also asked the question "how much further away" without hinting that you would have to move up as well as back to obtain the results showm. Of course, in reality it's a simple test: the flaws in the question didn't take a lot of finding though: both of the above points were blindingly obvious .... Bob -- Whatever you Wanadoo: http://www.wanadoo.co.uk/time/ This email has been checked for most known viruses - find out more at: http://www.wanadoo.co.uk/help/id/7098.htm
