SIMPLE = T / FITS STANDARD; Fits required field. BITPIX = 16 / FITS BITS/PIXEL; Fits required field giving the data size. NAXIS = 2 / NUMBER OF AXES; Fits required field giving the number of array dimensions. NAXIS1 = 867 / X AXIS NO. PIX; Fits required field giving the number of pixels in the X axis. NAXIS2 = 867 / Y AXIS NO. PIX; Fits required field giving the number of pixels in the Y axis. BLANK = -32768 / ARRAY NULL VALUE; used to indicate pixels not to be used. HISTORY Created by tiftofits version 1 on 2005-04-06 at 21:26:29; Information field generated by reduction code. HISTORY 1-3 pixel sized dust and emulsion pits removed by Laplacian filter BSCALE = 1.0000000 / REAL = DATA*BSCALE + BZERO; intensity conversion formula. Arbitrary here. BZERO = 0.0000000 / BUNIT = 'INTENSITY' / ARBITRARY UNITS ORIGIN = 'MT. WILSON' / TELESCOP= '60 FT' / OBJECT = 'SUN' / DATA-TYP= 'CA SPECTROHELIOGRM' / DATE-OBS= '1937-01-04' / YEAR-MO-DA TAVG-UT = 16.6171875 / AVERAGE TIME, U.T.; Recorded in the logbook as the walk-clock reading during the exposure. LAMBDA = 3933.6818848 / WAVELENGTH (ANGSTROMS) SCALPIX1= 333.2025452 / X PIXELS PER INCH; This is for the binned pixels in this file, the original is 3 times greater. SCALPIX2= 333.3123169 / Y PIXELS PER INCH; Same as above. CRPIX1 = 434.9388428 / Ref point1.; This is the pixel location of the image center in this file on the X-axis. CRPIX2 = 432.7873230 / Ref point2.; This is the pixel location of the image center in this file on the Y-axis. CDELT1 = 0.00293718 / Solar Scale Axis 1.; Pixel size in solar radii for the X-axis. CDELT2 = 0.00289886 / Solar Scale Axis 2.; Pixel size in solar radii for the Y-axis. RX-RY = -4.50000000 / Radius x minus Radius y.; Determined difference between the orthogonal radii. GRADXP = 352.18020630 / Average Slope X plus.; These slopes are at the solar limb and use pixel units from the full-scale images. GRADXM = 467.26135254 / Average Slope X minus.; Slopes are differences between pairs of rectangular averages. GRADYP = 322.42788696 / Average Slope Y plus.; Each rectangle is 5 px wide by 7 px long in the direction of the slope. GRADYM = 270.19070435 / Average Slope Y minus.; The slope number is effectively the digitization number difference for a separation of 8 full-scale pixels. SCSLOPXP= 42.50000000 / Scattered Light Slope X plus.; These slopes are averages over arcs of radii between 10 and 25 pixels larger than the final image radius. SCSLOPXM= 28.37500000 / Scattered Light Slope X minus.; If the edge or other solar image is too close the averaging range is reduced accordingly. SCSLOPYP= 43.37500000 / Scattered Light Slope Y plus.; The scattered light slope is used to correct the limb slope in finding the solar radius. SCSLOPYM= 42.56250000 / Scattered Light Slope Y minus.; Comparison of these numbers to the corresponding numbers above indicates the importance of scattered light on the image. YEAR = 1937 / Year of observation MONTH = 1 / Month of observation DAY = 4 / Day of observation IMAGE_NO= 1 / Image_No; This is a sequence number we have assigned based on the order of image extraction from each month so that each image has a unique identifier. SCANID = '20041025-9' / ScanId; This identifier gives the date of scan followed by a sequence number based on the order of scanning during the day. PLATE_NO= 'C1422' / plate_no; This is the plate number as written on the paper envelopes and/or the plate itself. PLTYPECD= 1 / PlateTypeCode; This identifier will allow us to distinguish between the CaK series and other image series. OBSTYPE = 'K2-SN' / ObsType; The direction of spectroheliograph scan as recorded in the logbook. TIME = '8:37:00' / time; The Pacific Standard Time of the observations as recorded in the logbook. IMAGQUAL= 3 / Image_Qual; A quality assessment number assigned visually by Javaraiah Javaraiah when coordinating the solar images with logbook entries. LGBOOKPG= '361226_370112' / Logbook_Page; The logbook pages are identified by the range of dates covered. These can be viewed at ftp://howard.astro.ucla.edu/pub/obs/logbooks/ CORANGLE= NIL / Correction_angle; Where available this is the angle between the y-axis and the line from the south to north solar poles. LGCOMMNT= 'NIL' / LogComments TGCOMMNT= 'NIL' / TagComments EXTRES = 1 / ExtRes; This is assigned by the extraction program and is 1 if the extraction was successful. EXTQUAL = 0.9913936162028835 / ExtQual; This is a measure of the extraction quality, it is near unity for a good extraction and less for a poor extraction. FILENAME= 'K19370104-01-20041025-9'/ FileName; This is the full name of the file without directory information. IMAGWDTH= 2601 / ImageWidth; This is the original image x-dimension in pixels. IMAGLNGT= 2601 / ImageLengt; This is the original image y-dimension in pixels. EXSUBSAM= 1 / ExtSubSample; Subsampling factor used in extracting the image from the original. Unity means no subsampling. SCRESUNI= 2 / ScanResUnit; tif standard value indicating that inches are used for the next two entries. SCANXRES= 999.607666015625 / ScanXres; The number of x-direction pixels per unit as indicated by the value in SCRESUNI. SCANYRES= 999.9369506835938 / ScanYres; The number of y-direction pixels per unit as indicated by the value in SCRESUNI. POSINSCN= 1 / PosInScan; This is the vertical position of the plate in the full deck scan. Values are 1 (top), 2 (middle) or 3 (bottom) for scans of the CaK plates using the present plate holder. HORPOSNM= 2 / HorPosNum; This is the horizontal position of the extracted image on the full deck scan. HORPOS = 'B' / HorPos; This is the same info as HorPosNum but in a MWO convention (A=1, etc) used in tagging and often written on the plate. PLXOFFST= 0 / PlateXoffset; This is the X-axis offset for the edge of the photographic plate. PLYOFFST= 0 / PlateYoffset; This is the Y-axis offset for the edge of the plate as calculated from the plate sizes in each scan. IMXOFFST= 2603 / ImageXoffset; This is the actual x-offset for the image found through the extraction process. IMYOFFST= 784 / ImageYoffset; This is the actual y-offset for the image found through the extraction process. LGDTDATE= '3/24/2005 13:50:11'/ LogDataEntryDate; This is the date the logbook information was transcribed into the database. LGSERIAL= NIL / LogSerial; Not used at present. TGDTDATE= '11/9/2004 11:25:49'/ TagDataEntryDate; This is the date the image was connected to its logbook entry. TGSERIAL= 5347 / TagSerial; A unique ordinal number assigned during the tagging process. EXFILLOC= '/1937/1/' / ExtFileLoc; The subdirectory path from a starting directory to the directory holding this file. SCFILLOC= '/2004/10/25/' / ScanFileLoc; This subdirectory path from a starting directory to the directory holding the full deck scan. SCFRAME = 0 / ScanFrame; An ordinal number indicating which full deck template was used for the image extraction. EXTDATE = 'Sun Apr 3 04:24:46 2005'/ ExtDate; The date the extraction was carried out. The same image may be extracted at different times with different extraction parameters so scans with different extraction dates could differ. SERIAL = 10913 / Serial; A unique serial number assigned to this image (not used in our processing). NPIXDUST= 11625 / Number of dust and pit pixels replaced.; This is from the image cleanup at the beginning of the radius finding algorithm. RADIUS_X= 340.46 / X-direction Radius; Determined radius in the x-direction using the image coordinates. RADIUS_Y= 344.96 / Y-direction Radius; Determined radius in the y-direction using the image coordinates. AVE_INTS= 17742.5937500 / Average Intensity Value; Average of the intensity over the image. AVE_IRMS= 211.5505219 / Ave. RMS Intensity Variation over 5x5 Arrays; the rms variation in the intensity over the whole plate. SUNEAR_F= 1.0167167 / Sun-Earth Distance Factor; Calculated from the JPL ephemerous and is included here for convenience. RADSCORE= 1 / Radius Solution Demerits, < 6 is good; This demerit factor is covered by other pages on the web site. END