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Comparison Achromat and ED star images -Rigel


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About this observation
Peter Anderson
Time of observation
14/03/2020 - 14:00
Observing location
Brisbane Australia
150mm F8 Achromat and ED optical tubes
As per text

This is a reduced image of a compilation showing the star images formed by each telescope. Because of the simpler draw tube on the achromat, there was definitely some off axis sagging when it was racked out using the barlow lens to record these images, so the images are not symmetrical.  The achromat optical tube has now been sold, so the experiment can not be repeated.

The purpose of the experiment was to compare the results between telescopes of identical aperture and focal length, using the same equipment (barlow lens & camera) at the same ISO and range of speed settings. 

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