Step by step

Step 1

Position your tripod then mark the ground where your tripod legs lie. We used acrylic paint because it’s weatherproof but can be removed with a kitchen scouring pad and water. Alternatively, screw the tripod shoe to a wall or sturdy object.

Step 2

Fit the camera lens with a dew heater. Set the lens to manual focus, then focus the camera on a bright star or planet using the live view and 10x zoom. It’s vital to get good focus for each session, so don’t rush this step.

Step 3

Point the camera, with the celestial pole in exactly the same place in the frame for each session. Set the camera to continuous mode, shutter speed to 30 seconds, ISO to 800 and aperture to f/3.5. Lock the remote shutter cable so it takes a sequence.

Step 4

After each session, put the lens cap on then shoot 20 to 30 dark frames. This will help to remove dark signal noise and hot or cold pixels from your images in processing. Repeat Steps 2 and 3 during different months throughout the year.

Step 5

Stack each night’s data separately. Open StarStaX, drag and drop your images, then add any dark frames. Untick any images with aircraft in them. Select ‘Gap filling’ mode and, if needed, tick the ‘Subtract dark frames’ box. Click ‘Stack’, then save the image.

Step 6

In Photoshop, paste each session’s image as a layer on top of another. For each layer, set the blend mode to ‘Difference’, use ‘Free transform’ to align, and set the blend mode back to ‘Normal’. Adjust the opacity until each layer’s stars have equal brightness.