Canon EOS 6D and Rebel T7i must be the same...?

Discussion in 'My Astrophotos' started by ROBERT T SCHAEFER JR, Aug 27, 2018.

  1. ROBERT T SCHAEFER JR

    ROBERT T SCHAEFER JR Cyanogen Customer

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    Even though they are two different sizes ... I think they still image at the same mmF/L per 'Configuration' .


    These images at 9360mm F/L thru a 152mm A+M Refractor(OfficinaStellare) 1200mm F/L using a Canon EOS 6D 35mm DSLR and a
    Canon EOS Rebel T7i crop-factor 1.6 DSLR imaging M27 at this extreme F/L and both DSLR images "PinPoint Astrometry" 'solving'
    at the same 9360mm F/L for 188xpwr might be proving the two kinds of 'sensors' are seeing the same thing while acquiring the image ..
    but the crop-factor 1.6 'sensor' sees less area that the 35mm 'sensor' .
    There is a FITS for each jpg and the jpgs are Annotated with info .
    The 6D images are from Bin1 to Bin3 and Bin3 and 'solve' and the one Rebel image is the same as the Bin3 and Bin3 and
    the same image of the Rebel is first a "Resize" from 3.72 micron pixels at Bin1 to 6.555 micron pixels and the Bin3 and Bin2 and
    the image 'solved' ... all three 'solved' with the GSC in MaximDL Pro V6.16 ,
    this seems to prove to me that the Rebel T7i doesn't have a magical magnification seeing an 'object' closer.. it is just presenting and
    'object' closer as a view magnified image ... ?m.m
     
  2. JoshuaHufford

    JoshuaHufford Cyanogen Customer

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    Oct 10, 2014
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    Robert, not trying to be rude but many of us here have tried to explain this to you already, no there is no magical magnification to any camera.

    It all boils down to the focal length of your telescope, the size of your imaging sensor, and the size of your pixels, that is all you need to care about. These 3 factors determine the field of view (amount of sky your camera sees) and the arc seconds per pixel (amount of sky each pixel sees). THAT IS ALL THAT MATTERS, STOP THINKING IN TERMS OF MAGNIFICATION! Magnification has no meaning whatsoever when it comes to imaging the sky.

    I've posted this for you before, on this page is a very simple program to download, please do so and it will be a very helpful tool for you. It allows you to input the focal length of your telescope, imaging size of your sensor, and your pixel size, it then gives you the FOV and arc seconds per pixel of your setup, again all the information you need to know.

    http://www.newastro.com/book_new/camera_app.html
     
  3. Colin Haig

    Colin Haig Staff Member

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    Josh - I've noticed he never replies to our responses. Am not sure if he doesnt know how, or if he is ignoring our advice.
     
  4. JoshuaHufford

    JoshuaHufford Cyanogen Customer

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    I know, I just thought I'd try one more time.
     
  5. Doug

    Doug Staff Member

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    Sep 25, 2014
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    I'll chime in.

    Magnification is a meaningless concept in a photo. You can change magnification just by putting it on a bigger monitor, or zooming in.

    The pixel size on the sky, in arc-seconds is:

    Pixel Size (arc-seconds) = 206 * Pixel Size (microns) / Focal Length (mm)

    The size of the camera array, in arc-seconds, is:

    Image size (arc-seconds) = Pixel Size (arc-seconds) * number of pixels.

    Divide by 60 to get arc-minutes.
     

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