For vertical dials I would still rather stick with an SLR with a long lens (and a tripod!) because of the effects of perspective correction on the gnomon. Incidentally, the effect of a rising front / perspective correction lens can be more or less equalled - at no cost except a smaller image - by resolutely pointing the camera horizontally in front of your eye rather than tilting it upwards. You need a wider angle lens from the same distance, or alternatively have to move further away; and then you need to enlarge the image more as it will include the wall up to the dial and lots of ground (half the picture). Moving further away helps with the gnomon distortion, too - looking at it not up its length.
The perspective correction or shift lens (and the view/technical camera equivalent Super Angulons and the like) is very expensive because quite apart from the mechanics it has to produce good images a long way off the optical axis - which is what you are doing when you move it right up its travel to take the high sundial. While John's photo of his Flandrau dial well illustrates the correction of the lines, if you look at the nodus it appears to lie NNE of its shadow, whereas the sun was really somewhere in the SE at the time. That's meant with no disrespect to his adjustment of the view of the dial plane, it's just a fact of geometry. But it occurs to me that one big advantage of a digital camera in all this is that with an ordinary horizontal dial on a high pedestal (not so easy with a very big dial, I agree) you can hold the digital camera at arm's length vertically over the dial and press the shutter, immediately examine the results, and repeat until you're quite satisfied. You will get the proper edge-on view of the gnomon (though its top will appear bigger as it's nearer the camera), whereas correcting perspective of a photo taken from the side appears to fold the gnomon down away from you. When I try this overhead method with a film camera I often wait days or weeks to receive a skewed blurry print of half a dial or one of my own feet. Andrew James
