Description

This is a 22-minute exposure beginning about 1:30 am. The light in the sky wasn't visible - it looked totally black. I could just barely see the horizon against a very, very faint gray glow. The sky light was just one of the pleasant surprises in this shot. The clarity of the reflection was another.

This type of shot isn't hard, but it does require a tripod and cable release. The light is so low you don't need mirror lockup; just lock the shutter open in bulb mode.

I took several test shots to determine the best combination of ISO and aperture. I used ISO 400 for exposures of a minute or so, but for this long one, I went with the lowest I could get: ISO 100.

I used my widest lens, the Sigma 10-20, at 10 mm and the widest aperture, F/4.

Stars will start blurring at about 30 seconds, depending on focal length. I wanted really long star trails, so knew it had to be longer. Nothing magic about 22 minutes - I was just eager to see the results after that time!