RC71_ElephantTrunk_30M_Reducedstars

SIMPLE = T / file does conform to FITS standard

BITPIX = 16 / number of bits per data pixel

NAXIS = 3 / number of data axes

NAXIS1 = 5305 / length of data axis 1

NAXIS2 = 3947 / 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

DATE = '2025-08-31T19:48:40' / UTC date that FITS file was created

DATE-OBS= '2025-08-30T06:44:05.682331' / YYYY-MM-DDThh🇲🇲ss observation start,

ROWORDER= 'TOP-DOWN' / Order of the rows in image array

EXPTIME = 1830. / [s] Exposure time duration

OBSERVER= 'DaveMartin' / Observer name

FILTER = 'mixed ' / Active filter name

FOCALLEN= 350.737 / [mm] Focal length

CENTALT = 54.9986111111111 / [deg] Altitude of telescope

CENTAZ = 317.111111111111 / [deg] Azimuth of telescope

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 ASI2600MC Pro' / Instrument name

CCD-TEMP= 0. / [degC] CCD temperature

SET-TEMP= 0. / [degC] CCD temperature setpoint

GAIN = 100 / Sensor gain

OFFSET = 12 / Sensor gain offset

CVF = 0.2636 / [e-/ADU] Electrons per A/D unit

FOCPOS = 33178 / [step] Focuser position

FOCTEMP = 11.8599996566772 / [degC] Focuser temperature

OBJECT = 'SH2-131 (Elephant' / Name of the object of interest

AIRMASS = 1.21983318371154 / Airmass at frame center (Gueymard 1993)

SITELAT = 39.3488888888889 / [deg] Observation site latitude

SITELONG= -78.8116666666667 / [deg] Observation site longitude

OBJCTRA = '21 39 20.786' / [H M S] Image center Right Ascension

OBJCTDEC= '+57 29 27.840' / [D M S] Image center Declination

RA = 324.836610257537 / [deg] Image center Right Ascension

DEC = 57.4910666057748 / [deg] Image center Declination

CTYPE1 = 'RA---TAN-SIP' / TAN (gnomic) projection + SIP distortions

CTYPE2 = 'DEC--TAN-SIP' / TAN (gnomic) projection + SIP distortions

CUNIT1 = 'deg ' / Unit of coordinates

CUNIT2 = 'deg ' / Unit of coordinates

EQUINOX = 2000. / Equatorial equinox

CRPIX1 = 2672.5 / Axis1 reference pixel

CRPIX2 = 2050.5 / Axis2 reference pixel

CRVAL1 = 324.747824907617 / [deg] Axis1 reference value

CRVAL2 = 57.4824553633667 / [deg] Axis2 reference value

LONPOLE = 180. / Native longitude of celestial pole

CDELT1 = -0.000614246927725233 / [deg] X pixel size

CDELT2 = 0.000614206279736693 / [deg] Y pixel size

PC1_1 = 0.0703084306141619 / Linear transformation matrix (1, 1)

PC1_2 = 0.997525300222793 / Linear transformation matrix (1, 2)

PC2_1 = -0.997523181919709 / Linear transformation matrix (2, 1)

PC2_2 = 0.0703384783228858 / Linear transformation matrix (2, 2)

A_ORDER = 3 / SIP polynomial degree, axis 1, pixel-to-sky

A_0_0 = 0.

A_1_0 = 0.

A_0_1 = 0.

A_2_0 = 4.89066047335137E-08

A_1_1 = -1.13699260318849E-07

A_0_2 = 8.88087755245384E-09

A_3_0 = -3.60518222915414E-11

A_2_1 = 1.99430347807434E-12

A_1_2 = -4.29462526384469E-11

A_0_3 = 5.24288869933521E-12

B_ORDER = 3 / SIP polynomial degree, axis 2, pixel-to-sky

B_0_0 = 0.

B_1_0 = 0.

B_0_1 = 0.

B_2_0 = 4.30983502497688E-09

B_1_1 = 5.4146437330906E-08

B_0_2 = -8.88925649093415E-08

B_3_0 = 4.12794324800495E-12

B_2_1 = -3.74618908909417E-11

B_1_2 = -1.00543801866771E-12

B_0_3 = -3.94613448307762E-11

AP_ORDER= 3 / SIP polynomial degree, axis 1, sky-to-pixel

AP_0_0 = 0.000139740010779307

AP_1_0 = -1.82239358159642E-07

AP_0_1 = -8.4138737291895E-08

AP_2_0 = -4.90148985454187E-08

AP_1_1 = 1.13913781653622E-07

AP_0_2 = -8.92446734610106E-09

AP_3_0 = 3.61155920306058E-11

AP_2_1 = -2.01516667479249E-12

AP_1_2 = 4.30465296034464E-11

AP_0_3 = -5.23184577751946E-12

BP_ORDER= 3 / SIP polynomial degree, axis 2, sky-to-pixel

BP_0_0 = -0.000115849746318576

BP_1_0 = -2.59611120412717E-08

BP_0_1 = -1.14540555151699E-07

BP_2_0 = -4.28394848362944E-09

BP_1_1 = -5.42484460901311E-08

BP_0_2 = 8.90212701461562E-08

BP_3_0 = -4.1315140701688E-12

BP_2_1 = 3.75267800275289E-11

BP_1_2 = 9.97567010975472E-13

BP_0_3 = 3.95212136605438E-11

HISTORY Photometric CC (algorithm: SPCC)

PIERSIDE= 'EAST' /

CAMID = '1E1E560D0B020900' /

ADCBITS = 16 / Bit depth of camera sensor ADC in current mode

BIASADU = 121.16593933105469 / ADU for bias level (no photons) at current sett

EGAINSAV= 0.26355 / Electrons per ADU at saved bit depth

RELGAIN = 2.964 / Multiplicative gain relative to minumum

RDNOISE = 1.77 / Read noise in electrons

SUBEXP = 15 /

COLORTYP= 'RGB' /

DATE-END= '2025-08-30T07:27:08.7834822' / System Clock:Est. Frame End

DATE-AVG= '2025-08-30T07:05:37.2329070' / System Clock:Est. Frame Mid Point

JD_UTC = 2460917.7955698255 / Julian Date at mid exposure

END

Done