Hi Doug I posted this on the PixInsight forum but had no response. I just wanted to check it wouldn't be caused by a camera problem. The images look fine, and the ACP log I had checked with Bob who said it was fine. Unsure what is happening here. Will try and check it with MaxIm today Peter I am using the BPP script. On the last two objects I have imaged using LRGB, I am having an issue with Image Calibration for the Red channel. It will work fine only if I take out the flat frames, so there seems to be an issue with them only. But when I compare the images, and the FITS headers for the Red flats, and to the LGB flats, there appears to be no difference. I had obtained the flats using ACP Sky Flats and hadn't previously had an issue, but am now. I get the same error message : Applying bias correction: master dark frame... Dark frame optimization thresholds: Td0= 0.00030316 (162416 px= 0.968%) Computing master flat scaling factors... Error: Zero or insignificant scaling factor for flat frame channel# 0. (empty master flat frame image?) <*failed*> It will produce this whether I have a master flat, or the individual flat frames. In the FITS header for red, which is the same for the LGB there is : BITPIX 16 BSCALE 1.0000000000000 ( or so) BZERO 32768.000000000 I am using a master bias and master dark which work fine on the other channels. Unsure what is going on. Have tried it through Image Calibration instead but produces the same result. Any suggestions? Thank you.
Can't comment on other people's software. If you post the images we can have a look. Upload FITS to ftp.diffractionlimited.com, incoming folder.
can't seem to get the files from my computer into the incoming, doesnt want to be moved there ( using a mac) unsure if this works : https://www.dropbox.com/sh/9lzdkusm54079y9/AABdVkurW7PQvQw25Ps7scnra?dl=0
tried to calibrate with MaxIm, but the master dark has 0.00 sec on it but it was actually 600s and it brings up an error "no exposure duration was specified"
However you generated the Master Dark, it has no EXPTIME keyword. Either regenerate it correctly (no idea what you did wrong - different software), or manually edit the FITS header to add the missing information. SIMPLE = T / file does conform to FITS standard BITPIX = -32 / number of bits per data pixel NAXIS = 2 / number of data axes NAXIS1 = 4096 / length of data axis 1 NAXIS2 = 4096 / length of data axis 2 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 PROGRAM = 'PixInsight 01.08.05.1352' / Software that created this HDU COMMENT PixInsight Class Library: PCL 02.01.07.0873 COMMENT FITS module version 01.01.05.0411 COLORSPC = 'Grayscale' / PCL: Color space RESOLUTN = 72. / PCL: Resolution in pixels per resolution unit RESOUNIT = 'inch ' / PCL: Resolution unit THUMBIMG = 'Thumbnail' / PCL: File includes thumbnail image extension OBSERVER = 'Peter Brackenridge' / Observer who acquired the data INSTRUME = 'SBIG STX-16803 3 CCD Camera' / Name of instrument IMAGETYP = 'Dark Frame' / Type of integrated image FILTER = 'Lum ' / Name of filter BINNING = 1. / Pixel binning factor XORGSUBF = 0. / Subframe origin, X axis YORGSUBF = 0. / Subframe origin, Y axis TELESCOP = 'Alluna RC18' / Name of telescope FOCALLEN = 3726. / Effective focal length in mm APTDIA = 4572. / Effective aperture diameter in mm APTAREA = 164173. / Effective aperture area in square mm COMMENT Integration with PixInsight 01.08.05.1352 HISTORY Integration with ImageIntegration module version 01.16.01.0447 HISTORY Integration with ImageIntegration process HISTORY ImageIntegration.pixelCombination: average HISTORY ImageIntegration.outputNormalization: none HISTORY ImageIntegration.weightMode: don't care HISTORY ImageIntegration.scaleEstimator: iterative k-sigma / BWMV HISTORY IMAGEINTEGRATION.RANGEREJECTION: RANGE_LOW = 0.000000 HISTORY ImageIntegration.pixelRejection: percentile clipping HISTORY ImageIntegration.rejectionNormalization: none HISTORY IMAGEINTEGRATION.REJECTIONCLIPPINGS: LOW = yes high=yes HISTORY IMAGEINTEGRATION.REJECTIONPARAMETERS: PC_LOW = 0.200 pc_high=0.100 HISTORY ImageIntegration.numberOfImages: 5 HISTORY ImageIntegration.totalPixels: 83886080 HISTORY ImageIntegration.totalRejectedLow: 4(0.000%) HISTORY ImageIntegration.totalRejectedHigh: 10307(0.012%) HISTORY ImageIntegration.scaleEstimates_0: 1.3258e-04 HISTORY ImageIntegration.locationEstimates_0: 1.5946e-02 HISTORY ImageIntegration.imageWeights_0: 1.00000e+00 HISTORY ImageIntegration.zeroOffsets_0: +0.000000e+00 HISTORY ImageIntegration.rejectedLow_0: 1 HISTORY ImageIntegration.rejectedHigh_0: 2142 HISTORY ImageIntegration.scaleEstimates_1: 1.3301e-04 HISTORY ImageIntegration.locationEstimates_1: 1.5930e-02 HISTORY ImageIntegration.imageWeights_1: 1.00000e+00 HISTORY ImageIntegration.zeroOffsets_1: +1.525879e-05 HISTORY ImageIntegration.rejectedLow_1: 2 HISTORY ImageIntegration.rejectedHigh_1: 1951 HISTORY ImageIntegration.scaleEstimates_2: 1.3318e-04 HISTORY ImageIntegration.locationEstimates_2: 1.5930e-02 HISTORY ImageIntegration.imageWeights_2: 1.00000e+00 HISTORY ImageIntegration.zeroOffsets_2: +1.525879e-05 HISTORY ImageIntegration.rejectedLow_2: 0 HISTORY ImageIntegration.rejectedHigh_2: 2196 HISTORY ImageIntegration.scaleEstimates_3: 1.3338e-04 HISTORY ImageIntegration.locationEstimates_3: 1.5915e-02 HISTORY ImageIntegration.imageWeights_3: 1.00000e+00 HISTORY ImageIntegration.zeroOffsets_3: +3.051944e-05 HISTORY ImageIntegration.rejectedLow_3: 1 HISTORY ImageIntegration.rejectedHigh_3: 1901 HISTORY ImageIntegration.scaleEstimates_4: 1.3304e-04 HISTORY ImageIntegration.locationEstimates_4: 1.5915e-02 HISTORY ImageIntegration.imageWeights_4: 1.00000e+00 HISTORY ImageIntegration.zeroOffsets_4: +3.051944e-05 HISTORY ImageIntegration.rejectedLow_4: 0 HISTORY ImageIntegration.rejectedHigh_4: 2117 INPUTFMT = 'FITS ' / Format of file from which image was read
That's interesting. I just Calibrated them in Pixinsight and that is how they turned out. Am unsure how to write in the exposure time into FITs I just calibrated the Flat frames in MaxIm instead, and then used the Master Flat into the ImageCalibration and Batch processing script in Pixinsight and it worked okay. So there is something that is going wrong with the creation of the Red Master Flat in Pixinsight that seems to be the problem. Unsure what to about that. Maybe I will start calibrating in MaxIm from now on. It's certainly simple to do Peter
My suggestion (I’m not a Diffraction employee) is to calibrate in MaxIm exclusively. It does a fantastic job, and the calibration wizard is brilliant simple to use. Once you have calibrated images, move on to the fancy stuff in whatever other software.
Peter. In addition to the advice given above there are a couple of other issues with your files in the dropbox. In PixInsight > Edit > Global Preferences > File I/O settings, deselect 'Enable thumbnail embedding by default' as this confuses other image calibration software that do not know how to handle embedded thumbnails. It also makes working in PI very tedious when thumbnails keep popping up when opening images. When you save an image you have the option of embedding a thumbnail if you want to, look for the checkbox in the save file dialogue, but unless you think it is needed then don't bother and certainly don't use the default option of automatically embedding. I have found that taking PI calibration masters into other vendors software rarely works properly first time, there are just too many save options within PI that have to be chosen just right for the package you are exporting to. However, I was able to calibrate your sample red channel image in PI, using both the BPP script and the stand alone Calibration Tool. In BPP when using previously created masters the check boxes must be selected to signify that masters are to be used, the default on opening or resetting the tool is that these are deselected. Click image below to view in full resolution. In the stand alone calibration tool when using existing masters the check box 'Calibrate' must be selected under 'Master Dark', the default on opening or resetting the tool is that this is deselected. Click image below to view in full resolution. HTH William.