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80mm BT

80mm BT

Current state of 80mm asymmetrical binocular telescope.

    Beautiful project. I worry that two diff lengths will cause a diff in magnification.  Perhaps you can move the shorter one forward, and thus make the image trains equal length.

    May 07 2019 03:16 PM



    The optical path lengths are the same at 400mm so magnification and field of view at each eyepiece is the same. The top tube has a 100mm longer path before the secondary and the lower tube has a 100mm longer path after the secondary. The light doesn't care where it turns the corner as long distance traveled is the same. The views from 20X to 80X look great and I really feel more immersed using both eyes. I've posted a few comments about the views under the "What Did You see last night" thread in Binoculars.


    Do a search for petertinkerer to see his 3D printed hardware for this arrangement.


    Take care,


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