Vega, 30 s exposures with a 135 mm lens
Using the astrotracer to track the stars.
The astrotracer is a function of Pentax cameras that allows taking long exposures of the stars. Because stars rise in the East and set in the West they are constantly moving in the sky and leave a trail on long exposure photography.
The astrotracer, by moving the sensor inside the Pentax camera, keeps up with the movement of the stars, making them appear as pinpoints instead of lines.
On most Pentax cameras you will need to get the O-GPS1 GPS module in order to make the astrotracer function available.