Quote:
Originally Posted by knightrider
I'm looking at a second scope ATM.
I have a 10" Synta which is good, but I am considering a 6" dobsonian as a grab and go.
Are there quality differences between the gso and synta models of this size?
I do believe the synta ones don't put pyrex glass in the 6". And none of the 6" models include a 10:1 focuser...
Anything I should be looking out for?
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When building a scope, mass production or custom, there comes a point where producing a scope costs exactly the same, be it a 4" or 10". In the end, to cut costs it becomes a function of components & care in assembly. At f/8, primary mirror is likely to be spherical as these are cheaper to fabricate. As you've noticed, the 6" has a simple single speed focuser. It also may only have rubber I-rings instead of springs in the primary mirror cell - you'll never be able to properly collimate the scope if this is the case. You NEED to check this out before you make a purchase. At this year's IIS Astro Camp one participant's brand new 6" dob had O-rings, not springs. We also couldn't get the secondary mirror 100% collimated as the spider was placed too high above the focuser. We fixed up their scope as best we could, and the image quality improved markedly - but not to what it should be.
You get what you pay for.
Mark, I didn't think of coating quality also being a factor. Thanks for that
