Quote:
Originally Posted by LewisM
I have VERY light sensitive eyes, and I can easily detect the shadow of the central obstruction and it really bugs me.
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Lewis - central obstruction shadow or vignetting occurs when the image of the central obstruction in the exit pupil is actually hardly smaller than your eye pupil. If you have noticed this then you must have used low magnifications giving an exit pupil much larger than your eyes' opening and your eye is just not opening up nearly as much as you think either due to ambient light levels and or age. This is not a fault of the telescope - you need to calculate the exit pupil and judge whether you are likely to lose light - is my eye going to be 8mm pupil in this lit urban enviroment or more likely 3mm ? Perhaps I should use a higher magnification.....