Angie and Mark Underwood
Star Gazing in Scilly
It's been a while since we posted anything to our blog and with the 2019 season now well and truly upon us we thought we would start writing about some of the things we enjoy in Scilly.
We thought we would start with the Scilly night sky. We are not astronomers or serious star gazers but we have always enjoyed and been mesmerised by the night skies we get in Scilly. We are extremely fortunate that we get very little light pollution and most of Scilly is classed as a dark sky area with only a small area affected by light pollution around Hugh Town and that obviously much less less than in a city or town on the mainland. The skies are still good in town but you don't have to walk far to be truly in a dark sky area. The link is an interactive map of where to go to avoid any light pollution. https://www.nightblight.cpre.org.uk/maps
You can enjoy the sky at any time, if you are out walking at night just take a moment to turn off your torch and look up. If you want to really have a chance to see the best of the skies a little bit of planning will be advantageous and perhaps a late night will be required. If you want to see the Milky Way, knowing where it is going to be and at what time the best of it will be visible will save a wasted late night. The moon state is important, the less moon visible the better for the stars and milky way. The weather obviously plays an important role and a cloudless night will again give the best views. I use a cheap phone app 'The Photographer's Ephemeris' which gives all the information about the night (and daytime) skies that you are likely to need including Moon rise and set, Milky Way rise and set, Galactic Center rise and set (the most spectacular part of the milky way) and its location from any given point on a map. There is also a free desk top version https://app.photoephemeris.com
The desk top version of XC Weather gives a good indication of cloud cover in percentage terms for any given hour https://www.xcweather.co.uk/forecast/TR21_0PA.
Also worth checking out is http://www.seasky.org/astronomy/astronomy-calendar-current.htmlwhich gives details of astrological events such as meteor showers for watching shooting stars.
It stands to reason that as Scilly is a great place to see the night sky, it is also a great place to try astrophotography. If you are new or relatively inexperienced in relation to astrophotography as I am, youtube is a good source for information and instruction from beginner to expert techniques. A basic kit requirement will be a DSLR or Mirrorless camera, preferably with a full frame sensor, a wide angle lens and a tripod. A bridge camera can also be tried. The images displayed here are relatively simple as they are each taken from a single image. Taken on a Sony mirrorless camera with a 24 mm lens at f1.4, The camera was set on a sturdy tripod with the ISO set to 3200 and a shutter speed of 20 seconds. A longish shutter speed is required to allow the sensor to gather enough light but if it is too long the stars will lose their shape and start to show light trails. As a rule of thumb divide 500 by your focal length. So in my case it was 500 ÷ 24 = 20.83 therefore 20 seconds. These settings are a starting point only.
Put your camera on manual to allow all of the settings to be set without the camera changing them as you activate the shutter release. Open the aperture up as far as it will go (the lowest number ie f1.4, f2.8 f4 depending on lens). Focus manually to infinity. Shoot in raw to allow latitude for post processing.
The camera sensor is able to gather much more light than the eye which is why more stars are visible on your photograph. Process the file in lightroom or similar. Again there are numerous tutorials on youtube giving advice on post processing milky way photographs.