JnEr1 'single' image showing 'dark-calibration' difference

Discussion in 'My Astrophotos' started by ROBERT T SCHAEFER JR, May 4, 2021.

  1. ROBERT T SCHAEFER JR

    ROBERT T SCHAEFER JR Cyanogen Customer

    Joined:
    May 13, 2018
    Messages:
    264
    CanonEOSII RebelT7i modified UV-IR @ Hutech thru a 152mmA+M Refractor(OfficinaStellare 1200mmFL) using a TeleVue .8XReducer/Flattener for an effect of 950mmFL and a BreakThrough X4-UV 49mm filter with a step-ring to 48mm .

    {[{[{[ With this 'single' 347secISO-AUTO(as ISO400) 'light' frame I did "Convert Color" , "Make Pixels Square" , and Kernal Filter-Median5x5" . Then , I did a "Set Calibration" 'Calibrate' with a 481secISO100 DARKMaster using 'Dark Frame Scaling Manual : 0.0100 ' which is down to ' 1/100th ' because ' 4.0000 or 1.0000 or 0.5000 only artifacts showing only the 'darkmaster' content . ]}]}]}]} .
    This method with ' Manual' seems to help Hydrogen Alpha images to remove the edge light haze in an image . In MaximDL Pro V6.16 in the "Set Calibration" there is a ' ? ' sign in the top right and you tap on it and then tap on a topic in the "Set Calibration" command which would be in the 'Dark Frame Scaling' small window and a paragraph appears with descriptions of the options . Auto-Optimize can sometimes fail and you might have to redo it or use Manual and set a number that you think might be working OK and use that method if the others fail to remove the 'dark-current' blurs . The Manual setting I'm using could be OK when needed instead of the Auto-Optimize which uses statistics from the 'background' which a 'color' image probably has , but a HydrogenAlpha image might not have enough to work with and may fail , so , Manual might be the best method . xxxx

    ########## I will try eventually with a HydrogenAlpha filter on a Canon Lens in the area of Cygnus and I'l set in the RebelT7i's 'Menu' for ISO-AUTO a value that will only use ISO6400 and do some 6min and 7 min 'light' frames and then I can use any 'calibration' DARKMaster I want to use like 481secISO100DARKMaster which might have a thicker content and the ' Manual 0.0100 ' setting and I'l see if that does the trick . I check each 'dark' frame I use for any sign of 'banding' and I don't use it if the frame has the 'banding' and I delete it . xxx ##########
     

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