Quote:
Originally Posted by alocky
And a 20" newt is an APO. In fact it's better than an APO because every wavelength of light will focus at the same spot, not just three.
And once you get into the 6"-8" APO territory where you have a hope of seeing deep sky objects, albeit quite dimly, you will find that the cost function is parabolic, not linear.
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OK, my 8" GSO dobsonian mirror APO cost me about half of my 70mm Vixen APO, both second hand. So yeah I guess the cost function is not linear... still tryin to work out the shape of the parabola though
I'm still tryin' to see any DSOs though it too, but I'm fairly optimistic now I
Quote:
Originally Posted by alocky
have a hope
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