These are really good.
Question: How do you focus in the dark? I assume you have some sort of artifical lighting to help with this and once locked in take the long exposure.
For shot number one I had my tripod set up and the shot framed long in advance; then it was just a matter of waiting, hoping the light will cooperate and do something gorgeous. So, in short, I was in place and ready to shoot while there was still plenty of ambient light to focus by and the focus setting never changed while I took a series of shots.
Shot number two is one of a series that was taken in ambient light as well and focus was not an issue.
For shot number three I was shooting in almost total darkness (only half an hour or so after shot number two was taken) but the focus was locked in from that previous shot. I wanted to see the night sky in the shot as it appeared to naked eye but I also wanted to get the rock formation exposed like you see it in the shot. To get everything I wanted I needed to expose the night sky for twenty seconds. To illuminate and warm up the rock formation like you see it, I used a flashlight (with an incandescent bulb) to light paint with. The rock formation was "painted" for the last seven or eight seconds of the total exposure.
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