Long Star Trails with Normal Foreground - How Was This Done?

[anonymous]

I've recently been discussing a picture on this site and there's been quite a bit of musing about how this shot was created:


(on Cambridge Gallery, Page 6)

We would be appreciative if you left a note describing the technique, although I readily admit that there's a certain appeal to leaving one's magic a mystery :-)

[McQ]

This shot is a single photograph and does not use HDR or other blending. The photo was taken not long after sunset, when the sky still had a significant blue tint (but yet stars were beginning to appear). This is why there are more stars visible in the top (darker) than in the bottom (lighter). The long star streaks are from three factors: a long focal length (232 mm), the length of exposure (96 sec) and the distance from the North Star (lens is facing nearly perpendicular to its direction). It was timed such that, in a long exposure, the light of the sky would balance that of the soft perpendicular light escaping a window curtain nearby.

Please also see this website's page on common obstacles in night photography for an overview.

Also, here's the technical settings used for this photo:
Canon EOS 20D, Canon EF 70-200mm f/2.8L IS USM
96s f/5.6 at 145mm (232mm at 35mm equivalent) and iso200

Thanks for the interest.

[taken]

well well well somebody here has surely mastered the art of long exposures congrats mrmcq i love these long exposure shots......they are like suspense thrillers.......just waiting for the shutter to finally close,gives the ultimate thrill