Since I can remember, my favorite skiing images always contained a beautiful sun star. This inspired me so much so that I began utilizing this in my landscape photography. I have learned that the star is only part of the overall effect of looking right into the sun when taking a picture. There are additional wonderful aspects of the light, such as dark shadows to manipulate into dramatic or mysterious shapes. There are highlights reflecting the specular dots from water or anything shiny. Then there is the star!
Since the sun star is a man made or introduced effect of the light diffracting around a specular light source there is nothing natural about it. This has not stopped me from treating it with as much respect as a waterfall, bristlecone pine or any other natural subject. I have a range of acceptance to the different types of stars created by different lenses. Just like any subject, there are good ones and some that are not so good. A sun star is created when a lens is stopped way down -- the wider the focal length the better. For example, a 200mm lens requires an f-stop of no less than f/22 to create the star effect from small speculars and possibly f/32 for a star from the sun. The problem is that with almost all telephoto lenses, stopping down past f/11 typically makes for soft images. To make Muench Stars, you will need a focal length of at least 28mm wide, stopped down to at least f/16. Another factor in lens choice is prime vs zoom. Though, there are some fine stars to be made from wide zooms the best in my opinion have always been with prime lenses.
I always remove all filters, even the UV. This eliminates any additional flare from occurring in areas away from the sun. In fact, because of the additional elements in a zoom lens there can be very intrusive flares created at certain focal lengths as well as certain particular angles from the sun. A fisheye makes a great star, but this is not the only lens that stars well. Some of my favorite lenses for starring have been fisheye lenses, and of all the Nikkor 16mm. This little beauty creates a star at F/8 that only gets larger the more fuel you give it.
In my opinion stars can be ridiculous and the new and very sharp Nikon 14-24mm gets the trophy for the most ridiculous star. There is something overboard about this star. It’s like too much of a good thing. Subjectively the sun star or a Muench star, is a second read in an image, not the main subject. The Nikon 14-24 lens creates a “super star” that demands too much attention. My very favorite star is now made from the Leica 18mm. I can’t wait to experiment with Leica’s new 15mm F2.8 lens.