Atlas Images of Spectroscopic Objects

File Format: FITS binary table

Name: spAtlas-pppp-mmmmm-fff.fit, where pppp is the spectroscopic plate number, mmmmm is the MJD of observation of the last exposure included in the spectro reduction, and fff is the fiber id.

Produced by: dp

Used by:

Size: About 115 Kb per fiber, 107 Mb per plate.

Archived?

Description

Contains the atlas images for all objects observed on a given spectroscopic plate.

There are 10 atlas images per file. The first 5 are u,g,r,i,z, for the best reduction. The second 5 are u,g,r,i,z for the target reduction. If the atlas image cannot be read for any reason, a dummy image of size 0,0 is placed into the fits file. If the object has run 0, as can happen for hot standars for example, the fits file may be empty.

Primary Header


SIMPLE  =                    T                                                  
BITPIX  =                   16                                                  
NAXIS   =                    2                                                  
NAXIS1  =                  128                                                  
NAXIS2  =                  148                                                  
BZERO   = 3.27680000000000E+04                                                  
BSCALE  = 1.00000000000000E+00                                                  
EXTEND  =                    T                                                  
VERSION = 'v5_3_53 '                                                            
DERV_VER= 'v8_15   '                                                            
ASTR_VER= 'v5_13   '                                                            
ASTRO_ID= '2002-09-19T13:40:11 27771'                                           
BIAS_ID = 'PS      '                                                            
FRAME_ID= '2002-09-19T14:09:21 08329'                                           
KO_VER  = 'devel   '                                                            
PS_ID   = '2002-09-18T15:17:24 15246 camCol 1'                                  
CREATIME= 'Thu Sep 19 19:12:28 2002 UTC' / The local time when this file was cre
SEED    =             93054723 / Seed for photo random number generato          
REF_BAND=                    2 / index of band used for canonical cent          
RUN     =                 1907 / Imaging run number                             
RERUN   =                   21 / Processing rerun number                        
CAMCOL  =                    1 / Column in the imaging camera                   
FIELD   =                  153 / Field sequence number                          
DARK_VAR= '9.61 15.6025 1.8225 7.84 0.81' / Per-pixel variances at zero DN; DN^2
GAIN    = '1.62 3.32 4.71 5.165 4.745' / Mean gains of amplifiers; e/DN         
SOFTBIAS=                 1000 / software "bias" added to all DN                
ID      =                   24 / Object id, as in run-rerun-camcol-fie          
FILTER  = 'u       '                                                            
SKY     = 'best    '           / best= latest reduction, target= the i          
COMMENT = 'Target is useful to see why we did what we did'                      
COMMENT = 'Best is often a better view of the object'                           
PLATE   =                  266 / spectroscopic plate                            
MJD     =                51630 / 2400000-MJD of last spectroscopic obs          
FIBER   =                  327 / fiber id                                       
COMMENT = 'As in plate-mjd-fiber'                                               
MAPID   = '0266-51615-01'      / Mapping between targets and fibers us          
DATE    = '2003-02-27'         / date of file creation                          
ORIGIN  = 'SDSS@Fermilab'                                                       
TELESCOP= 'SDSS 2.5m at Apache Point Observatory'                               
INSTRUME= 'SDSS imaging camera'                                                 
AUTHOR  = 'Jim Annis'                                                           
COMMENT = 'These atlas images have been  extracted from'                        
COMMENT = 'the standard FITS heap format that the SDSS'                         
COMMENT = 'PHOTO pipeline produces.'                                            

END