Wednesday 25 December 2019

Shetland Star Trails

Star trails are a great way to show Stars in a different way. Often if you are photographing stars you are best to go for a well know constellation other wise people seem to be less impressed


 Star trails are easy to do, providing the conditions are favourable. First you need a clear night with no wind, difficult in Shetland

 The first three photos was taken at ISO800 30 seconds for 60 shots and then combined in a free software program Star trails. There are three different methods to combine photos, my favourite is the comet trails



The bottom image, photographed at Jarlshof in the south mainland is just 10 photos at ISO 800 30 second exposure


Have a great Christmas and don't forget to join Shetland Aurora Hunter on facebook

Thursday 12 December 2019

Aurora colours

There is no doubt that its great to see the Aurora no matter what colours are revealed. If we manage to see the Aurora with our own eyes then we will mostly see it in Black & White. This is because our eyes are made up of cones and rods

The cones reveal detail and colour in good light, in poorer light such as nightime then the rods which are located at the edge of the eye can only give a suggestion of colour mainly green, if we see any at all

Our atmosphere consists of oxygen and nitrogen and these are hit by charged particles blasted out from the sun. As they collide those hitting the Oxygen create a green and red Aurora while those hitting the Nitrogen create a blue or deep red/purple colour

There are many shades of these colours . We normally encounter a green yellow  colour while when the Aurora is very active then pillars created can be topped with red. Very occasionally a deep red colour can also be seen at the bottom of the Aurora

The strong green light occurs at around 120 - 180km's while red aurora can be both lower of higher

 

There is no doubt that a very active Aurora with large rays will be on most peoples bucket list

We are lucky that we can see many different variations in Shetland


To keep up to-date with Aurora activity in Shetland, make a point in joining Shetland Aurora Hunter on facebook