Example header for FITS extension 1:
====> xtension 1
XTENSION= 'IMAGE   '           /
BITPIX  =                   16 /
NAXIS   =                    2 /
NAXIS1  =                 1072 /
NAXIS2  =                  201 /
PCOUNT  =                    0 / Number of pixels following data
GCOUNT  =                    1 / Number of groups
BZERO   =       32768.00000000 / Pixel-data have 32K offset.
BSCALE  =           1.00000000 / Pixel-data are not scaled.
INHERIT =                    T / Extension inherits primary HDU.
EXTNAME = 'extension1        ' / Extension name
EXTVER  =                    1 / Extension version number
IMAGEID =                    1 / Image identification
DASCHAN =                    1 / Number of readout channel
WINNO   =                    1 / Number of readout window
CHIPNAME= 'CCD201            ' / Name of detector chip.
CCDNAME = 'CCD201            ' / Name of detector chip.
CCDCHIP = 'CCD201            ' / Name of detector chip.
CCDTYPE = 'CCD201            ' / Type of detector chip.
CCDXPIXE=           0.00001300 / [m] Size of pixels in x.
CCDYPIXE=           0.00001300 / [m] Size of pixels in y.
AMPNAME = 'RH                ' / Name of output amplifier.
GAIN    =           0.20000000 / Nominal Photo-electrons per ADU.
READNOIS=           1.00000000 / Nominal Readout noise in electrons.
SATURATE=       65535.00000000 / Highest value that is unsaturated
MAXBIAS =       65535.00000000 / Maximum expected bias level
RTDATSEC= '[1:1072,430:630]                ' / Location in d-space for RTD.
DATE-OBS= '2008-01-15        ' / Date at start of integration
UTSTART = '14:34:02.476      ' / UT at start of integration
EXPOSED =           4.20000000 / [s] Exposure time
EXPTIME =           4.20000000 / [s] Exposure time
ELAPSED =           4.20000000 / [s] Integration time
DARKTIME=           4.20000000 / [s] Integration time
CRVAL1  =           1.00000000 / Reference value on 1st axis in primary WCS
CRVAL2  =         430.00000000 / Reference value on 2nd axis in primary WCS
CRPIX1  =           1.00000000 / Reference pixel on 1st axis in primary WCS
CRPIX2  =           1.00000000 / Reference pixel on 2nd axis in primary WCS
CUNIT1  = 'pixel             ' / Units of  1st axis in primary WCS
CUNIT2  = 'pixel             ' / Units of  2nd axis in primary WCS
CD1_1   =           1.00000000 / Transformation matrix for primary WCS
CD1_2   =           0.00000000 / Transformation matrix for primary WCS
CD2_1   =           0.00000000 / Transformation matrix for primary WCS
CD2_2   =           1.00000000 / Transformation matrix for primary WCS
PROJP1  =           1.00000000 / Projection coefficient for primary WCS
PROJP3  =           0.00000000 / Projection coefficient for primary WCS
PV1_1   =           1.00000000 / Projection coefficient for primary WCS
PV1_2   =           0.00000000 / Projection coefficient for primary WCS
PV2_1   =           1.00000000 / Projection coefficient for primary WCS
PV2_2   =           1.00000000 / Projection coefficient for primary WCS
END