upgrades to BST`s but which focal lengths?

[sbj]

I have ordered myself a 10" Dob (Orion XT10g), which is f4.7.  

I am thinking about upgrading my eyepieces from bst starguiders  to Explore Scientific 82°s.

Apart from the increase in GOV, am I likely to gain much?  And if so, what two focal lengths should I prioritise?  The scope comes with a 2" 28mm and an illuminated 12mm.

Thanks for any advice.

[sbj]

FOV........ predictive pain

[Reeny]

Go for whichever ES 82^o will give you around 200x magnification.

At 1200mm, my 200P dob needs a 6mm (6.7mm is closest at 180x)

I think your 10" Orion is the same.

The 28 / 12 / 6.7mm ES will give you 42x / 100x / 180x

Then add one more eyepiece depending on the focal length of your scope, and your viewing habits.

4.7mm is an ambitious 255x magnification - nice for the moon, but struggling to obtain good views on other targets.

An 8.8mm might be a good bet, although it would be quite close to your stock 12mm.

There are so many "if's and but's"

I would hang on and try out your current BST's on the Orion first, to see where your preferences lie.

If you don't know what sizes to get - other people will be struggling to advise as well.

[John]

You may want to consider getting a coma corrector too. 82 degree eyepieces will show more off axis coma (which the scope produces, not the eyepiece) than 60 degree ones. It would be a shame if that extra field of view that you are buying is not sharp. 

Reeny's advice is good I think - hang on to the BST's and use them with the scope for a bit before deciding where to go next. As you have already made the big step away from stock eyepieces the further performance increases (apart from the FoV) will be less pronounced and cost more to achieve.

I'm not saying don't upgrade but perhaps take a little time to decide what next step would suit you best.

[KevUU]

I was going to say "wait and see once you've had a play" but others have said it better than I would have. So, what they said

[Charic]

..ditto.. Try what you have first.

Its said the BST's fair well at f/5 and slower.  Hopefully, you`d be best to advise us on this situation?

Some of the BST's will be fine, but FL below 12mm would, I assume, highlight more coma than you experience already. And as stated, unless some correction is used, is more apparent.

[spaceboy]

I have owned BST's in all focal lengths http://stargazerslounge.com/topic/128026-finally-on-the-bst-firm/?hl=%2Bfinally+%2Bon+%2Bthe+%2Bbst+%2Bfirm#entry1320938 and currently do and have owned 6.7, 11, 14 & 18mm ES 82°. The BST are a good eyepiece and in the shorter focal lengths I couldn't really fault them given there price. Yes they show coma but as already said this is a result of faster scopes and not any fault of the eyepiece. The ES 82° are not just a step up in FOV but also offer a better corrected FOV along with a much more quality feel about their build. The views through them I feel far exceed their current U.S. imported price point. The only real niggle is that they do seem to suffer some lateral colour towards the edges but this is also something I have noticed in the 7, 16 & 28mm 82° SW Nirvana/ WO UWAN. 

The trouble with eyepieces is that it is very much a personal thing. Some people get distracted by coma others by astigmatism http://www.umich.edu/~lowbrows/reflections/2007/dscobel.27.html . In a similar way some people just can't get on with CA in Achromatic refractors yet others don't find it a problem. One thing to remember is a coma corrector will help tidy up coma but it won't fix other aberrations.