SIMPLE = T / file does conform to FITS standardBITPIX = -32 / number of bits per data pixelNAXIS = 3 / number of data axesNAXIS1 = 2638 / length of data axis 1NAXIS2 =

SIMPLE = T / file does conform to FITS standard

BITPIX = -32 / number of bits per data pixel

NAXIS = 3 / number of data axes

NAXIS1 = 2638 / length of data axis 1

NAXIS2 = 2638 / length of data axis 2

NAXIS3 = 3 / length of data axis 3

EXTEND = T / FITS dataset may contain extensions

COMMENT FITS (Flexible Image Transport System) format is defined in 'Astronomy

COMMENT and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H

BZERO = 0. / Offset data range to that of unsigned short

BSCALE = 1. / Default scaling factor

PROGRAM = 'Siril 1.4.0-beta3' / Software that created this HDU

FILENAME= 'Light_M 81_240.0s_Bin1_20250920-043834_0004.fit'

DATE = '2025-09-21T14:49:38' / UTC date that FITS file was created

DATE-OBS= '2025-09-20T03:34:33.627754' / YYYY-MM-DDThh🇲🇲ss observation start,

IMAGETYP= 'Light ' / Type of image

ROWORDER= 'BOTTOM-UP' / Order of the rows in image array

EXPTIME = 240. / [s] Exposure time duration

TELESCOP= 'ZWO AM5N' / Telescope used to acquire this image

FOCALLEN= 433.958 / [mm] Focal length

XBINNING= 1 / Camera binning mode

YBINNING= 1 / Camera binning mode

XPIXSZ = 3.76 / [um] Pixel X axis size

YPIXSZ = 3.76 / [um] Pixel Y axis size

INSTRUME= 'ZWO ASI533MC Pro' / Instrument name

CCD-TEMP= -10. / [degC] CCD temperature

SET-TEMP= -10. / [degC] CCD temperature setpoint

GAIN = 101 / Sensor gain

OFFSET = 70 / Sensor gain offset

CVF = 0.994093239307404 / [e-/ADU] Electrons per A/D unit

STACKCNT= 11 / Stack frames

LIVETIME= 2640. / [s] Exposure time after deadtime correction

EXPSTART= 2460938.47976765 / [JD] Exposur

Done