A Spot of Astrophotography

I saw an advert in the paper this week for tips on astrophotography brought to you by Cannon. So I took my Nikon (ha! take that advertising) out into the evening chill and snapped a few shots of the sky. The darkness wasn't incredible and the haze was building, but it was good enough. Actually what first got me outside was the terrific sound of some military jets flying around. I thought for a moment it was the Avro Vulcan which I once saw fly over Southampton, this had the same gravity, but by the time I was outside the lights were on the horizon. But looking up I noticed the Pleiades glowing attractively in the early darkness so I popped back to get my camera for a few test shots.
Some experimentations this time - high ISO, shooting RAW and Kelvin rated white balance. The high ISO ~1250 was recommended in the advert, but having read some astro photo websites such as Deep Sky Stacker [thanks to @cawhitworth] their conclusion is that high ISO doesn't help more light enter the lens so it a false economy. However, this time I wasn't going to be taking multiple identical shots to superimpose - might try that at the New Moon this weekend. The Kelvin white-balance was a discovery I made in Croatia this September and is a much more sturdy way to get the colours closer to what you see than any of the pre-sets with their +/- offsets. I have found that working around the 6000K level gives the best night-time recreation of the colour. As for shooting RAW - my aging 4-year-old MacBook Air can't really handle such mega files. To be fair it does do rather well, especially since the replacement of the SSD with a higher speed and capacity one shipped from OWC. But I can't afford 0.5 GB per mini shoot of only 20 files.
Wide Field Pleiades. © Nick Bailey
wide view East towards the Pleiades : 18 mm | f5.6 | ISO 140 | 30 sec
Pleiades. © Nick Bailey
Pleiades comparison : 70 mm | f7.1 | ISO 1250 | [L:5 R:2.5] sec
Pleiades. © Nick Bailey
Pleiades comparison : 70 mm | f7.1 | ISO 1250 | [L:10 R:5] sec
Pleiades. © Nick Bailey
Pleiades comparison : 70 mm | f5.6 | ISO [L:1250 R:100] | 30 sec
Pleiades. © Nick Bailey
Pleiades comparison : 29 mm | f7.1 | ISO [L:1250 R:500] | 10 sec
Capella. © Nick Bailey
Capella with shorter exposure and low ISO : 70 mm | f7.1 | ISO 100 | 10 sec
Capella. © Nick Bailey
Capella with longer exposure and high ISO : 70 mm | f5.6 | ISO 1250 | 30 sec
2014-11-17

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