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Juno
20-03-2017, 05:54 PM
Is it true that a 10" scope with a 1250mm focal length experiences colour aberration? how obvious is it to the observer when viewing a celestial object?

billdan
20-03-2017, 06:00 PM
Reflector telescopes do not have colour aberrations, they do however experience coma at short focal ratios (F5 in this case). So a coma corrector my be purchased if the user finds it annoying near the edge of the field of view.

anj026
20-03-2017, 06:25 PM
You may see colour aberration caused by atmospheric conditions. Particularly when viewing objects low in the sky.

Juno
20-03-2017, 06:27 PM
Thanks for explaining, makes sense now.

Saturnine
20-03-2017, 10:32 PM
Some eyepieces can introduce their own chromatic aberrations, so if you're seeing colour fringing in a Newtonian try changing to a different type or focal length eyepiece and notice if it has changed or gone away.