8" vs 10" Dob?

[azrabella]

I need some advice regarding the suitability of my collection of BST ED eyepieces on either the 8" (f/5.9) and 10" (f/4.7) Skywatcher Dobs, one of which I'm looking to purchase. Some say that I should really consider Baader or better ep's, but if this is the case, then rendering my current ep's redundant is probably a move too far. They work fine with my 6" (f/8). If a bigger aperture does require higher quality oculars, then I'll have to reconsider the venerable light bucket and think sct's. Any opinions please - practical rather than theoretical.

[kev100]

Hi there. They'll work fine in the 8 inch, but the longer focal length BSTs will struggle in the 10. I have a 5mm BST, and use it regularly with my 10-inch no problem (but then the fov is smaller, and I'm focussing only on the very centre of the view. I have looked through longer focal length BSTs in a 250PX and found the view to be poor (to my eyes): pincushioning and distorted stars around the periphery. However, I know others aren't bothered too much by these things.

I would suggest you get the scope you want first (for all the right reasons), and then get the EPs to suit. You should get a good price for the BSTs to fund further purchases.

Kev

 

[johninderby]

To me the 10” is the sweet spot for size and performance. Going up to the 12” will mean a much bigger and heavier scope.that may cause real portability issues for many users. If your budget allows for the extra cost then highly recommend going for the 10”.

[Charic]

I'm with Kev100 with regards to viewing on axis, not really caring much for what happens at the extreme edge of my field of view on my 200P-f/6.
That said, there's not a great deal untoward on my scope, so maybe down to my own eyes, as to what I see and think is right.

There are many folk here that use BST's on 10" scopes, but it's the  end user experience that counts. You need to find the eyepiece that works for your eyes?

I bought some Delos EP's for the same reason, thinking I'd need better eyepieces for my new purchase? but on the  present 8" their no better than what I have, so rather than spend more on getting EP's that would not prove beneficial for my present needs, I stopped collecting and sold my stock! I had also decided that I would keep the 8".

I've not looked through  a 10" or 12"  scope  (12" would be my choice over the 10", down to the focal ratio, and the larger aperture) but the 8" is still a fine scope for my needs.
 

[Ricochet]

I don't think it will make much difference. 12-8-5 will be fine in either, 25-18 will suffer in both. 

[Stub Mandrel]

Surely the f-ratio of the scope is going to have more impact than the aperture in terms of the demands they place on EPs?

My 10" dob doesn't show strange shapes around the edges of the view - but it's f6.3.