This is Yosemite Valley view, photographed last week about 730PM. The tricks to getting good star photography with out star trails are these:
Use a wide angle fast lens 10-30 mm, ideally 2.8 or faster
Use a camera that allows you to shoot at 800 ISO to 3200 ISO with little to no noise
Include the landscape in the scene
Expose at widest aperture and VIP, prefocus to a distant object manually as light is getting dim, and turn off auto focus to lock the focus. Do not touch the lens after that
Expose for about 10-30 sec, depending on the lens.
To avoid star trails divide the Focal length of the lens into 600 to give you the maximum exposure time to avoid star trails. Example, a 20mm lens allows up to 30 sec exposure. Bracket times/ISO's to see the best shot.
Use a tripod. Fire the shutter with a cable, wireless or self-timer to avoid camera shake
A tungsten white balance keeps the sky blue
Turn off long exposure noise reduction
In this image, El Capitan is on the left with night climbers and their head lamps.
Camera was a Canon EOS M with a 22mm pancake lens. ISO 1600, f2, 15 second exposure, fired with 2 sec self timer.
Enjoy, Jeff