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Flexible Image Transport System (FITS) is a flexible open file format for images, spectra, photon lists, data cubes etc. The data is stored in N-dimensional arrays or tables.

N.I.N.A. is capable of saving images in FITS format. The FITS format offers a variety of header meta information and N.I.N.A. will populate all available information into this header. A detailed list of all available Headers and their conditions is described below. Many applications can make use of these headers (e.g. PixInsight during processing).

Standard FITS Headers#

  • SIMPLE: true
  • BITPIX: 16
  • NAXIS: 2
  • NAXIS1: image width
  • NAXIS2: image height
  • BZERO: 32768
  • EXTEND: true

Image Headers#

  • IMAGETYP: Type of exposure (LIGHT, DARK etc.)
  • EXPOSURE: Exposure duration in seconds
  • EXPTIME: Exposure duration in seconds
  • DATE-LOC: Locale time at exposure start
  • DATE-UTC: UTC time at exposure start
  • ROWORDER: TOP-DOWN orientation of the image starting point. Details at

Observer Headers#

Taken from the Astrometry Options

  • SITEELEV: Elevation (currently taken from a connected telescope)
  • SITELAT: Latitude
  • SITELONG: Longitude

Target Headers#

Available when a target is set inside a sequence.

  • OBJECT: Name of object
  • OBJCTRA: Right ascension of target
  • OBJCTDEC: Declination of target

Camera Headers#

Requires a camera to be connected

  • INSTRUME: Name of camera
  • XBINNING: X binning factor
  • YBINNING: Y binning factor
  • GAIN: Gain
  • OFFSET: Offset (if camera can set an offset)
  • EGAIN: Electrons per A/D unit (only available for some cameras)
  • XPIXSZ: X-Pixel size
  • YPIXSZ: Y-Pixel size
  • SET-TEMP: temperature set point (requires a cooling unit)
  • CCD-TEMP: actual sensor temperature (requires a cooling unit)
  • READOUTM: Sensor readout mode
  • BAYERPAT: Sensor bayer pattern
  • XBAYROFF: Bayer pattern X axis offset
  • YBAYROFF: Bayer pattern Y axis offset

Telescope Headers#

Requires a telescope to be connected

  • TELESCOP: Name of telescope
  • FOCALLEN: Focal length (taken from equipment options)
  • FOCRATIO: Focal ratio (taken from equipment options)
  • RA: Current telescope's right ascension coordinates
  • DEC: Current telescope's declination coordinates

Filter wheel Headers#

Requires a filter wheel to be connected

  • FWHEEL: Name of filter wheel
  • FILTER: Current active filter

Focuser Headers#

Requires a focuser to be connected

  • FOCNAME: Name of focuser
  • FOCPOS: Current step position
  • FOCUSPOS: Current step position
  • FOCUSSZ: Step size
  • FOCTEMP: Temperature (requires temperature probe on focuser)
  • FOCUSTEM: Temperature (requires temperature probe on focuser)

Rotator Headers#

Requires a rotator to be connected

  • ROTNAME: Name of rotator
  • ROTATOR: Rotator angle in degrees
  • ROTATANG: Rotator angle in degrees
  • ROTSTPSZ: Step size

Weather Data Headers#

Requires a weather data source to be connected

  • CLOUDCVR: Cloud cover percentage
  • DEWPOINT: Dew point in Celsius
  • HUMIDITY: Humidity percentage
  • PRESSURE: Air pressure in hPa
  • SKYBRGHT: Sky brightness in lux
  • MPSAS: Sky quality in mags/arcsecs^2
  • SKYTEMP: Sky temperature in Celsius
  • AMBTEMP: Ambient air temperature in Celsius
  • WINDDIR: Wind direction: 0=N, 180=S, 90=E, 270=W
  • WINDGUST: Wind gust in kph
  • WINDSPD: Wind speed in kph