... >Another place to avoid LENR is with star trails. There are >two types of star images - short images to capture stars as >dots (typically under 30 seconds using the 500 divided by >focal length formula)... >
your suggestions are very much to the point, only one remark with regard to the formula to capture stars as dots: I anything but an expert here, but I recently made some initial experiments which suggested to me that for the d800, a formula of about 300 divided by focal length might be more adequate. However, I did these trial exposures here in Lahore, Pakistan, which is about the same latitude as the Northern border of Florida. In a few weeks, if I get some clear sky, I will do some more testing in Germany.