Star Trails over the Brian Joynes Observatory

~1 Hour of Star Trails taken at the Observatory, Austerfield. Aiming the lens towards Polaris the 'North Star' (as seen towards the top right), all other stars rotate around it.

Foreground: 5 x 30s @ISO 800, stacked in
Nebulosity to reduce noise.
Sky: 111 x 30s @ ISO 100 processed in
Photoshop for trails, then exposure blended with the foreground and
contrast/levels tweaks etc...
Nikon D750, Sigma 14mm @ f1.8