Astronomer how-to

How to Reduce Raw Telescope Images

Raw data needs cleaning.

Updated By the Career Education Institute Curriculum Team
Quick answer

Raw data needs cleaning. In short: gather; subtract; divide, then complete the remaining steps below.

Step by step

  1. Gather calibration frames.

  2. Subtract bias.

  3. Divide by flats.

  4. Remove cosmic rays.

  5. Align images.

  6. Stack.

Safety reminders for astronomers

  • Follow observatory safety
  • Protect eyes when observing the Sun
  • Follow data policies
  • Take care at high altitude

Hypothesis · Peer review · Grant · Protocol · Replication · Light-year: see the full astronomer glossary.

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