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    Re: 35mm Super Takumar Lens for CN on DSLR
    From: Greg Rudzinski
    Date: 2015 Aug 19, 10:43 -0700

    The 35mm Super Takumar lens calibration continues. For the lower altitudes the natural horizon is used (below 2200 pixels). The data points are a good fit with the artificial horizon data points. The last 10° of altitude down to sunset will have to wait for another day when there is a cloud free horizon. 

     

    Greg Rudzinski

    From: Greg Rudzinski
    Date: 2015 Aug 13, 09:00 -0700

    The first artificial horizon Sun observation by calibrated 35mm fixed prime lens has been made this morning. (see original image)

    Pixel count by Windows paint  3029 pixels x .57' = 1726.5' - 41.5' corr. = 1685' = 28° 5' AHs / 2 = 14° 2.5' Hs -3.8' ref. = 13° 58.7' Ho

    8/13/ 2015  UT 07:30:19  Lat 34° 10.5' N  Lon 119° 13.8' W

    GHA  36° 21.4'

    LHA  277° 7.6'

    DEC  14° 38.5' N

    Hc 13° 57.8'

    Ho 13° 58.7'

    Int 0.9' toward

    Az 81.6° true

     

    Very pleased with result :)

    Image settings: f8, ISO 200, 1/1000 sec, infinite focus.

    Double polarizer used on artificial horizon reflected Sun (blue). Solar film used on direct Sun (orange).

     

    Greg Rudzinski

    From: Greg Rudzinski
    Date: 2015 Aug 12, 13:53 -0700

    Attached is the correction graph for the Super Takumar 35mm lens on a Canon Rebel xti 10 MP body.  Looks to be just a single outlier for the artificial horizon data points. Three consecutive images were averaged for each point. Low altitude natural horizon image calibration to follow.

     

    Greg Rudzinski

    From: Greg Rudzinski
    Date: 2015 Aug 9, 16:39 -0700

    The 35mm Super Takumar legacy prime lens is spectacular on the Canon Rebel xti 10 MP body. Sharp edge to edge with a field of view of 38°. Minutes of arc per pixel is .57'.  A full calibration will follow. The good news is the price of $30 free shipping for a lens in mint condition. Haven't snapped a bad pic yet :)

    Greg Rudzinski



    Attached File: 

    (Super-Takumar-35mm-Sun.PNG: Open and save)

    Attached File: 

    (Canon-Rebel-DSLR-w-Super-Tak.jpg: Open and save)

     


     


    Attached File: 

    (Cal-35mm-Super-Takumar.jpg: Open and save)


    Attached File: 

    (35mm-Super-Takumar-Obs.-1.jpg: Open and save)


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