Safe Sunspot Imaging with the Raspberry Pi HQ Camera

Sunspots change daily and drift across the disk as the Sun rotates about once a month. With a certified white-light solar filter covering the entire front of the lens or telescope, the HQ Camera can record them safely.

Mission steps

1. Fit the filter first

   Attach a full-aperture solar filter securely to the FRONT of the lens or telescope before pointing anywhere near the Sun. Check it for scratches or pinholes every time.

2. Cover finders

   Cap or remove any finder scope and aim using the shadow of the telescope or lens, never by looking through it.

3. Connect the camera

   Attach the HQ Camera at prime focus or to a long lens and connect it to the Pi 5.

4. Capture

   Use short exposures and low gain, take a burst of frames and keep the sharpest.

5. Build a series

   Shoot at the same time each day and assemble the images into an animation of the rotating Sun.

Code

# burst of 20 short exposures (adjust --shutter in microseconds for your filter)
mkdir -p ~/sun/$(date +%F)
for i in $(seq -w 1 20); do
  rpicam-still -n --immediate --shutter 2000 --gain 1 \
    -o ~/sun/$(date +%F)/sun_$i.jpg
done

Tip: test every script on the bench before installing it in a moving machine.

Questions