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Algorithms

Apart from reading this page, you should also refer to the Where to start page and About DR4. The Data products page contains an introduction on how to use the data.

Imaging

Spectroscopy

Magnitudes
Classification & Morphology
Photometric processing flags IMPORTANT!
Photometric flux calibration
Conversion between SDSS magnitudes and UBVR_cI_c, and ugriz colors of Vega and the Sun
Astrometric calibration
Flat-field creation and quality
Sky measurement
Centroiding and psf determination (see how to reconstruct the PSF at any position).
Deblending
Resolve: making sure an object from overlapping observations is only included in a catalogue once.
Creation of imaging masks
Photometry QA description

Target selection
Tiling (assigning fibers & plate centers)
Reduction of spectroscopic data
- Extraction of 1d spectra
- Wavelength calibration
- Flux calibration: spectrophotometry
- Continuum fits and line measurements
Spectral type determination and redshift measurement
- Cross-correlation templates
Velocity dispersion measurements

Last modified: Tue Jul 26 21:49:50 CDT 2005