M11 and M20 'without any filter being used'

Discussion in 'My Astrophotos' started by ROBERT T SCHAEFER JR, Apr 29, 2019.


    ROBERT T SCHAEFER JR Cyanogen Customer

    May 13, 2018
    CanonEOSII RebelT7i 'mod. UV-IR @ Hutech' thru a TeleVue 2.5XPowerMate for 3000mmFL
    using a 152mmA+M Refractor(OfficinaStellare) for MaximDL Pro RAWMonochrome Autosaves
    for 66secISO1600 for twelve images and 'calibrated' and Astrometric Average stacked ... then the
    FITS was put into "ImagesPlus" to use various commands and color commands ... and then
    back into MaximDL Pro to "PinPoint Astrometry" USNO-A2 'solve' without restrictions and the
    smallest points of light are stars . : this images was done without using any added filter and this
    could indicate that a Breakthrough 4X UV 49mm filter with a step-ring could see the same light
    content or better as the only filter without altering the color of the stars .?..x
    = I saw on the Internet that some people did experiments with various UV filters and one image
    didn't use a filter and was a lot darker than a UV filter showed the same house in a daytime image
    and the X3 UV filter is a good one … the newer version is a Breakthrough X4 UV filter . I will try
    it when I get the chance on some 'objects' . = x
    \ this image of M20 is like the M11 because there wasn't any 'filter' being used /
    / when I try these 'objects' again at this focal-length I'l use a Breakthrough X4 UV 49mm filter and see
    if it does OK which might show that for some 'objects' only the X4 UV filter might do the job . \
    = one site did experiments with UV and ND filters and says the Breakthrough filters don't have 'vignetting'
    due to the filter and the filter holder being a thin low profile which can eliminate ' vignetting ' ? .=
    CanonEOSII RebelT7i 'mod. UV-IR @ Hutech' thru a TeleVue 2.5XPowerMate without using any 'filter' thru
    a 152mm A+M Refractor(OfficinaStellare) for 3000mmF/L as RAWMonochrome Autosave images taken
    thru MaximDL Pro V6.16 ... two 480secISO1600 and one 555secISO1600 and four 55secISO1600 -
    'calibrated' Astrometric Sum stacked ... then the FITS was put into "ImagesPus" for more commands and
    then back into MaximDL Pro to "PinPoint Astrometry" 'solve' . x
    + With these images I used a FLATMaster also which was 1sec for the ISO's of ISO1600 and ISO3200 for
    five 'flats' for each Master . I did RAWMonochrome Autosave FITS for the 'flats' and then I 'opened'
    the Folder into "ImagesPlus" and at a 10% 'default' image size and then press the 'magnify' button to
    increase the image size to 11% with the RebelT7i and then use the 'Stretch' for 'Auto-stretch' and the image
    will look normal ….. then 'open' the 'Line Profile' command window and 'check' the small box in the lower left
    corner and the window becomes active … then select from the 'dropdown' list ' Line Segment' and the
    'left-click' and drag a line across the image and let go and the statistic will appear in the 'Line Profile' window
    and show the saturation level of the 'flat' frame image . . . it is probably best to get the 'flats' to have a 50%
    saturation level or slightly less . The reason for this idea if it works is when you make the 'flats' into a
    FLATMaster in MaximDL Pro and then check the FLATMaster in "ImagesPlus" the same way with the
    'Line Profile' window .. you will see a slightly more saturated statistic and if using Average to make the
    FLATMaster it could be increasing the SNR and causing a more saturated result …. but they say a
    FLATMaster should be about 50% saturated to get a good result to equalize the pixels .
    If you had 'flats' that were 75% saturated and Average combined one hundred of them … the end result
    FLATMaster might be totally over saturated ???? but checking it in "ImagesPlus" in the 'Line Profile'
    window will show the saturation statistic . +
    I also noticed that using the FLATMaster done this way for the 1secISO1600 'flats' and using a white shirt
    covering the front of the Telescope for 'white' light on the sensor …. when I 'calibrated' the M11 and M20 images
    shown here there seemed to be more 'white dot' pixels that disappeared and then after "Convert Color" I used the
    "Kernal Filter-Median3x3" which worked OK and then "Kernal Filter-Low Pass" and then other commands . x

    { "ImagesPlus" has a command called 'Line Suppression' and on it's first tab you select the radio button
    for 'Verticle' or 'Horizontal' and it's second tab 'Enhance' you select a radio button for 'Light' or 'Dark' or
    'Light and Dark' and try it's default 3x3 by pressing Apply .. then try 5x5 and press Apply … the higher
    you go like with 9x9 or more … the stars get too large … so 5x5 seems to remove a dark Horizontal line thru an image , or maybe a white line in the Verticle . }
  2. Colin Haig

    Colin Haig Staff Member

    Oct 27, 2014
    Hi Robert,
    These are quite good.
    I'd recommend you learn the image processing capabilities in MaxIm instead of hopping through all these other programs.

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