The night sky

November was probably slightly outside the optimal season for astrophotography in the northern hemisphere but nevertheless finding myself in a dark sky area on a clear(-ish) night it would have been rude not to have a go.

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Newton in Bowland

This was the first time I’d tried the Nikon D800E for this type of photography but it handled well and combined with the Nikon 14-24 I was very happy with how it worked. The only problem came when I dropped and broke my torch meaning I had to use the light on my phone to check and change settings which was very fiddly with gloved fingers.

Looking at the EXIF data this was a 30 second exposure at ISO 800.  Now at 14mm this should have meant that the stars did not visibly start to “trail” which causes them to appear as short dashes rather than dots in the image.  This is based on the commonly used 500 Rule: 500 divided by the focal length of your lens = the longest exposure (in seconds) before stars start to trail.  In theory I had 36 seconds to play with but looking closely I think 20 seconds would have been better even though I would have needed to increase ISO to 1600.

Capturing the core of the Milky Way has become the “in” thing in astrophotography in recent years, driven in no small measure by improvements in DSLR technologies and greater availability of accessibly-priced cameras to the enthusiast.  One pre-requisite though is a reasonably clear sky along with an absence of light pollution. A Dark Sky site is ideal and the nearest to where I live is in the Forest of Bowland.  Choosing when to make the attempt it is useful to understand a little about the geometry of the Galaxy, and I found an excellent guide at Andrew Rhode’s website.  About half-way down the page is a really handy diagram which really makes it easy to understand when the best time to be out is and what time of the day/night is best. The explanations are clear and straightforward and I can recommend spending some time perusing Andrew’s site.

 

 

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