I can only supply more guesses rather than answers I'm afraid, but I also suspect that Bill is correct in thinking that it arises from internal reflection(s) rather than a pinhole.
The red patch around the sun's image seems to have the sun near the middle of its bottom left to top right diagonal, and the sun is about there in the whole picture: while it is very roughly one-third of the way from the bottom right to top left of the red patch, the opposite of the sun's position in the picture. This may indicate something about the vignetting or number of reflections, so one reversal would correspond to Frank's observation that the crescent was the wrong side, but I don't know whether the red area and image are closely related, so that for example the red patch is simply a vignetted spread of scattered light from the same imaging path. Also the "artifact" image is reasonably close to the "opposite" of the sun's position when looked at in the whole picture. The reflection in the water would not have any such correspondence with the artifact so I feel it is much less likely to be an image of the reflection in the water. However I am puzzled that the solar image is quite sharp, as if it had been correctly focused. It seems to be about 1/50 of the photo's diagonal in diameter. I'm not sure of the iPhone's camera characteristics but believe the diagonal coverage is very roughly 60 degrees; if so the image would seem to be a little more than twice the proper size. If that's correct, this also indicates it is not a direct image of a reflection, and may provide a further clue. Andrew James Secure Meters (UK) Ltd. is a registered company in England: 2199653 Secure House, Moorside Road, Winchester, SO23 7RX This correspondence is confidential and solely for the intended recipient(s). If you are not the intended recipient, you must not use, disclose, copy, distribute or retain this message or any part of it. If you are not the intended recipient please delete this correspondence from your system and notify the sender immediately. --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
