Sorry - another eyepiece one

[ramstar]

Need some advice please. having convincedmyself of the shortcomings of the 10mm & 25mm eyepieces that came with the SW200, I have begun to put together a variety of eyepieces which I hope will stand me in good stead in the years to come. Probably the simplest thing to do is summarise where I'm up to so far. I have a BST 5mm, Hyperion 8mm and a 32mm Panaview. I'm happywith these but this is the point where I'm doubting my stsategy! I have ES82 at 6.7mm & 14mm on order from the States but they are both on backorder so I'm not holding my breath that I will get them anytime soon. With the aim of replacing the original 25mm I have ordered an ES x 2 extender and Es82* 24mm, both in stock and on theirway. This I'm assuming will cover me not just with 24mm but also a 12mm with the extender. The extender used with the 14mm gives me 7mm (?) So should I cancel the 6.7mm altogether or swap it for something else? What do you guys suggest?

[Stargazer_00]

First things first, the ES82s are really good eyepieces

Is the extender the 2" version? Just to be sure. The 24mm is a 2" eyepiece. Russell (russ.will) did a revoew of the 1.25" ES extender in the review section, worth a read. Summary; it's good.

Ultra wide eyepieces in the 18mm+ area probably would benefit from a coma corrector, but this is your call. If you are happy with the hyperion (which are reportedly soft on the edges) then you might be fine with a little coma in these low mags. I'd expect the panaview is already showing a degree of coma and that doesn't seem to bother you as you havent said anything about it.

I personally quite like the ES82 6.7mm and it would, of course, be roughly a 3.5mm in the extender which is useful. An ES82 11mm is another possible choice.

I also quite like the 5mm BST and unless you are flush wouldnt advise the 4.7mm ES to replace it (I appreciate you didnt say this)

EDIT: Oh yeah, i also did a review of the ES82 eyepieces in the review section which might help

[ramstar]

Thanks for the reply. I'll be honest - I read the reviews and they were key to me going down the ES route. Yes, the extender is the 2" model which I understand can be used with 1.25" eyepieces

[Stargazer_00]

It can and it's a good choice for the 2" 24mm as well. A 2" barlow 2x would've made the eye relief of the eyepiece longer and possibly uncomfortably so. The telexentder will not do this so will convert the 24mm to a 12mm well, albeit with a much greater weight than a dedicated 12mm.

further to that could you give some feedback on the performance of the 24mm and the 2" extender? I suspect the 24mm will show some coma. certainly my 24mm meade uwa does. we have the same focal length so it would be a similar, or comparable view on a target such as the double cluster. rich star fields like this show coma far more than anything else, so its a good test.