Originally posted by JedlyMT Thanks for sharing! I am about to purchase the Rokinon 10mm that just came out for K mount and this is exactly why I'm getting it. Night photography.
Have you used the 500 rule before? If not, read about it. It's a good thing to know, especially since you have the equipment to get a great image without having the star trails. I would shoot in RAW if I were you, but the first shot looks more natural. And don't be afraid to boost that ISO!!
Star trails occur due to using pixel shift at night. In this case, the 30 sec.exposure becomes 120 seconds. While the stars are nice, the total landscape is the subject. As for why I chose pixelshift, it was for the better colors. Now, bulb mode is great for astro with the 10mm. An exposure at 130 seconds to 150 seconds will have minimal trailing in the frame central area, but with a lens that wide you will have trails at the edges, regardless.
I am confused, however about the 10mm rokinon being new. Rokinon is just rebadged samyang/bower, and the 10mm has been around for some time now. I bought mine last summer after reading about it for at least a year prior.