Star Trail Test Only, old stock. Will put in scrap. Just to share.
Mamiya RB67 + 50mm + Fuji Velvia 100 + f/8 + 4-5 hours.
As a rule of thumb:
f/11: 6-8 hour
f/8: 4-6 hour
f/5.6: 2-4 hour
f/4: 1-2 hour
Is use manual camera with manual lenses, you can set f/4 for the 1st hour, and switch them to f/8 or above for the rest of the 4> hours. So the starting point of the star trail is visible.
Not a good example, as we were camping, and wind is abit too strong. So I can't put the camera farther away from the carpark/tent. The line reflection on the car window, is the flashlight when I was trying to lightpaint the car. Hmm ... gotta careful next time.