Top 10 Rules of Thumb for Galaxy Fitting

(Actually, there are 11....)

  1. To save from making subtle yet serious mistakes, it is usually better work with data that have pixel values in [counts] rather than count rate [counts/sec] or other units, e.g. μJy, ergs/sec, etc..

  2. Make sure the background sky value is correct.

  3. Make sure the sigma image is correct.

  4. Use a good PSF for convolution.

  5. Use object masking and simultaneous fitting to remove neighboring contamination.

  6. Use the convolution box correctly/wisely.

  7. Start out simple, build up complexity.

  8. Be on the look-out for small object sizes/axis ratio, and any parameters enclosed in *...*.

  9. Look at the model images.

  10. Do not abuse high order parameters (Fourier modes, C0, bending modes, spiral structures, truncations).

  11. Avoid Using Constraint Files.

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