Quote:
Originally Posted by Pharian
By that do you mean an 8mm eyepiece would be about the highest usable magnification? I'm considering an 8.8mm 82deg ES at the moment, and perhaps an 18mm as well.
I don't have a heap of cash to dump into televues, and I'm happy with decent image quality rather than ultimate best of the best. I would rather grab 3 fair quality eyepieces than a whole box of plossls, many of which I no doubt wouldn't use. The 68/82 degree ES look like the business for my price range, and easy on the eyes. I'm not sure what mm would be recommended for a high/med/low range on my scope though.
Thanks for your help!
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Hi Chris
You could spend the next year reading every post on every forum about eyepieces and still not scratch the surface! I think I started but it got so confusing I just bought some to find out for myself what works and what doesn't. Your situation sounds very similar to where I was so I will offer some advice.
The ES 68/82° were at the limit of my price range too, I bought 3 of the 82's and they are outstanding. Prior to that I'd bought some plossls which although very nice quality and totally fine to look through, do not (for me) compare to the nice wide views and overall premium feel that the ES 82° offer.
Someone above posted that you really only need 3 eyepieces: low, mid and high power, and I tend to agree. The focal lengths to select to get those magnifications will depend on your scope which being an f/10 SCT will be different to say a 10" or 12" f/5 Dob (which I have).
I have the ES82 18mm, 11mm and 6.7mm which are 83x, 137x and 225x in my scope respectively. I also have a GSO 30mm Superview (68°) which gives me 50x and they are the only eyepieces I ever take out. I have a 2.2x Barlow as well if I ever want to go crazy with magnification but at 300-500x I've yet to see planets in any sort of detail.
Be aware that in the ES82 range the 14mm gets mixed reviews due to its field curvature (stars near the edge out of focus when ones near the centre are). I haven't looked through one myself so can't comment first hand but it did factor into my purchasing decisions. But it looks like you are considering the 8.8mm and 18mm anyway.
Those two would give you 227x (about the max I find usable most nights, which is what I get with my 6.7mm), and 111x with the 18mm. I love the 18mm but you do need to get in fairly close to it so might be an issue for spectacle wearers. The 18mm is the start of the 2" EP's in that range. The shorter lengths are 1.25".
All 3 of my ES 82° are glorious to look through, I can't say I've owned the equivalent Tele Vues to compare but at triple the price I don't intend to find out, unless someone loans me one to try. I'm sure they are absolutely superb also.
If you have SkySafari (I think this works even on the free version) you can put the specs of your scope in, as well as your eyepieces. In the settings you can get it to display the relative FOV of each as part of the crosshair which for me was a big help help in deciding on a good spread for most objects. There's no point getting EP's that are too close to each other in magnification, or of getting magnifications that are unuseable, so play around and select a good range of magnification over a few premium EP's, would be my advice. Mine were very reasonably priced delivered from the UK, PM me if you'd like details.