Sky background level measuring with ASTAP

🌌 Measuring Sky Background for Sensor Calibration

Accurately measuring the sky background level with your astroimaging setup allows you to calibrate your sky brightness sensor.

📋 Requirements:

  • 📷 Monochromatic camera with luminance filter
  • 💻 Software: ASTAP (or similar)

⚙️ Procedure:

  1. 🌐 Download and install ASTAP and the star database (H17 recommended) from https://www.hnsky.org/astap.htm
  2. 📸 Capture a 15–60 second exposure with your camera and Luminance (L) filter
  3. 🖼️ Open the image file in ASTAP
  4. 🧩 Click Solve to perform plate solving
  5. 🔧 Navigate to Tools → SQM Measurement
  6. ✏️ Enter the pedestal value — the mean value from the corresponding dark frame
  7. 📊 The SQM (Sky Quality Meter) value is displayed directly

✅ Your sky brightness sensor is now calibrated.

SQM measuring with ASTAP

Happy measuring!