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    Re: Ebbco Sun Shade Modification
    From: Greg Rudzinski
    Date: 2016 Oct 25, 13:54 -0700

    A complete set of filter replacement combinations for the older Ebbco will require using lighter mylar neutral density film as a single layer on the horizon mirror shade or stacked x2 , x3, or x4 on the index mirror shade to add to the dark solar film filter.  A source of neutral density mylar film can be salvaged from the heavy sunglasses handed out by optometrists post eye exam.  4 circular shades can be cut from one pair of these mylar wrap around sunglasses. Stack to the desired amount of shading into the  Ebbco filter frame then snap the retainer ring into place. I was able to complete and test this modification in less than an hour. Very helpful for horizon glare when observing a low altitude Sun. 

    Greg Rudzinski 

    From: Greg Rudzinski
    Date: 2014 Sep 1, 10:00 -0700

    Sun shades on many older Ebbco plastic sextants seem to degrade. The solution is to replace the filter with dark solar film (Thousand Oaks Optical). This will greatly improve the view of a bright Sun and reduce shade error over the original. If both index and horizon shades are modified then index error determination is improved. An artificial horizon image is also improved.

    The filter size is 1.6" in diameter. The mylar film can be cut using the original filter as a template.

    Greg Rudzinski

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