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Slide 2 Discovered in August, 2014 by Terry Lovejoy Was closest to Earth on January 7, ~4 th mag Periodic comet, next visit in 8000 years Now in Taurus, headed for Andromeda Gerald Rhemann, 12 f/3.6, Namibia Slide 3 Slide 4 Slide 5 Different rates create problems With star tracks Align on comet, not stars special routine Combine in usual way without removing outliers Jerry Lodriguss Slide 6 Without star tracks Align on comet (image 1) Align on stars (image 2) Combine using sigma clipping Slide 7 Comet image with stars removed by sigma clipping Slide 8 Combine star and comet image the tricky part Harry Page method using PixInsight Some background on PixInsight First, a disclaimer Cutting edge image processing and analysis tools for a broad range of technical imaging applications Basically an image processing toolbox with over 80 tools Slide 9 From Pleiades Astrophoto, S.L., Valencia, Spain Not a paint program, big difference from PS Available for PC, MAC, Linux, etc $270 USD; all updates included; no refunds, but 45-day trial Is it hard to learn? NOT intuitive and very little written documentation Similar to PS in this way steep learning curve, but doable Slide 10 Warren Keller videos, 3 now available, $65 Harry Pages (UK) videos Free www.harrysastroshed.com www.harrysastroshed.com Lightvortex Astronomy, Kayron Mercieca Well written workflows, including DSLR Great for doing those first images Gibraltar Astronomical Society website Drake Visual extensive list of resources Bottom line doable and worthwhile Slide 11 Is PixInsight a substitute for Photoshop? No, IMHO they are complementary Strengths of Photoshop focused editing (painting) Layers and masks Curves and levels Cloning and painting Camera Raw noise reduction Carboni Tools and other plugins Is PixInsight a substitute for CCDStack, Images Plus, DSS, Nebulosity, Registar, etc? Yes Slide 12 Strengths of PixInsight ScreenTransferFunction Slide 13 DynamicBackgroundExtraction (DBE) and ABE Slide 14 HistogramTransformation Slide 15 CurvesTransformation Slide 16 Other tools I find useful Aligning and combining may replace Registar DynamicCrop MaskedStretch PixelMath RangeSelection ColorSaturation LinearFit Various noise reduction tools Wavelets direct noise reduction In my experience, overly smoothing Slide 17 Step 1 generation of star image Slide 18 Step 2 generation of comet image Slide 19 Step 3 generate star mask from star image Slide 20 Step 4 LinearFit to even out background Step 5 Add star image to comet image (with star mask) Slide 21 Step 6 Process combined image in PixInsight and Photoshop