That is a 25mm eyepiece in it, not what I will use in it for the wide angle, high brightness finder.
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The tube needs to be shortened another inch to get more infocus distance for the helical focuser to go between extension tube and eyepiece. Then a little touch up paint on the PVC. I am pleased with the optical quality of what was a $15 objective lens. This has not received much of a test; chromatic aberration is more of an issue as magnification and brightness go up
With the 25mm eyepiece, I get 6x, 7.5 degree field of view. The exit pupil is 10mm so roughly 75% of the light gathering capacity is lost going into a 5mm human pupil. That is still more than three magnitude deeper into the sky than the naked eye. I have no stars available for testing but used outdoors, the image is noticeably brighter than naked eye.
A couple possible choices of eyepiece for finder. The Svbony 25mm Plossl is cheap. It would give me 6x, but the Plossl design has a slightly wider apparent field of view, so i would get 8.2 degrees of sky. The Svbony 40mm Plossl would get me 3.8x and more than 10 degrees of sky. AstroMania 40mm is a bit wider so 12 degrees of sky. I am not sure that the extra field of view is really necessary and lower magnification means giving away light
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