Another Eyepiece Question

[cuivenion]

Hi all, I've been thinking of upgrading my existing eyepieces for a while. I've done all the reading I can on the subject and I've come to the conclusion that Televue Plossl's are probably the best investment as they will work well in any scope I'm likely to use. The BST Starguider/Explorer's looked interesting but I've read that they don't work as well in faster scopes. Same with the Baader Hyperions. It'd be great to get to my local astro clubs meeting to maybe have a look at different eyepieces first hand but unfortunately they're on a night that I work. After reading several threads and reviews I've come to the conclusion that it'd be best to get quality eyepieces rather than trying to skimp. Am I right in thinking that this is the way to go?

[Moonshane]

in a word, Yes. consider the eye relief will be shorter in the plossls but the quality better. none will have eye relief shorter than your 6.3mm plossl so if ok with that I'd go for it. even the 8mm has more.

[John]

Yep - Tele Vue plossls would be an excellent and future proof choice.

[ronin]

A BST Starguider is said to be good at f/5 and I have read someone saying OK at f/4.6 or f/4.8.

Your's will be f/5, so should not have a problem.

Once you get to f/5 you will have to consider the more costly eyepieces, f/5 seems to be the scope speed at which the performance step occurs.

TV plossl's are rated to f/4, but they stop at 8mm and are arounf £75 mark.

[cuivenion]

Aaargh, this topic is such a minefield lol. The slightly cheaper price and eye relief sound nice, but.... I'll have to make a decision at some point

[AlexB67]

One issue you may want to be aware of is using TV plossls, or many plossls for that matter tend to vignette in a barlow ( darken near the edges of the view) , even if you were to upgrade your barlow to a TV branded one. Just to point out if you are planning to build a collection around a barlow. A TV powermate ( also a magnifier like a barlow ) will avoid that.

Other than that not that I owned one, and only have one TV eyepiece, but the TV plossls should be an excellent choice

[AlexB67]

Aaargh, this topic is such a minefield lol. The slightly cheaper price and eye relief sound nice, but.... I'll have to make a decision at some point

If the eye relief is not a consideration and extra bit of FOV I would stick to your decision. In the end of the day the transmission of these plossls is superior, slightly sharper, and the well corrected view across the FOV even at f/5 is a factor. I also have an f/5 scope, the BSTs will still suffer a bit off axis in a way that a TV will likely not, though I say that without having used a TV plossl  but having used BSTs. I have enough confidence in saying going by others that between these to brands, the TV is better.  Only in comfort and extra bit of FOV will the BST win out. It is fair to say though if that is important to you the BSTs are very comfortable to use where a plossl will be less so.

edit: btw that is not to say the BSTs don't give very pleasant views at f/5, it depends how picky you want to be.

[John]

I've used Tele Vue plossls with a Celestron Ultima 2x barlow and only the 32mm showed any vignetting at the field edges. This was the same with any eyepiece with a field stop beyond a certain size.

You could build a pretty good TV plossl collection around 4 plossls the 2.5x Powermate:

32mm -> 12.8mm

20mm -> 8mm

15mm -> 6mm

11mm -> 4.4mm

The shortest eye relief would be around 8.5mm.

[wookie1965]

My scope is F5 and i have 4 BST explorers for the price they are brilliant best thing i ever did was upgrading to these, i have had some amazing views of Jupiter,Mars and Saturn. Saturn was my WOW moment blew me away.

[cuivenion]

One issue you may want to be aware of is using TV plossls, or many plossls for that matter tend to vignette in a barlow ( darken near the edges of the view) , even if you were to upgrade your barlow to a TV branded one. Just to point out if you are planning to build a collection around a barlow. A TV powermate ( also a magnifier like a barlow ) will avoid that.

Other than that not that I owned one, and only have one TV eyepiece, but the TV plossls should be an excellent choice

Thanks I'll bear that in mind.

[Charic]

cuivenion..........Hi, TeleVue lenses will be fine on your scope,  BST's will be fine on your scope. I suggest you try two of the BST's, with their 60° AFOV and good eye-relief, side-by-side, if you don't like them, send them back, Alan at sky's the limit, allows you to try them. If your not satisfied, just refund them. Start with the 8mm and 18mm or 8mm and the 12mm.

I haven't seen many Starguiders up for sale, and believe me, I've tried. My 25mm was the only one I saw during my purchases. People that have them love them for their capability and the price. You've nothing to lose by trying.

[AlexB67]

Thanks I'll bear that in mind.

Bearing in mind what John said he has tested them,  I have not personally, so perhaps it is not often an issue and that is goods news  . I was just going by some threads I recall reading elsewhere and heard this reported more than once, it will perhaps depend on the barlow make I guess and applies to the longer focal length ones.  

[cuivenion]

Thanks for the reply's, off to work now. I have more to think about now, looking at the price of the powermate especially. Charic that sounds like a great idea, the sort of thing I was looking for try before you buy!

[Charic]

......just note, you actually pay up front, for the BST's,  but the refund is available should you not like the EP's Alan is the Man to speak with. He'll see you right. Take care at work. 

[AlexB67]

Whatever you'll go for, I think you'll be happy with the improvement in contrast in either. the 25 MA I own also, as well as a 25 SW super plossl as well as the 25mm BST. The darker background is immediately noticeable when you try them out side by side, the BSTs render objects beautifully in that sense.

In terms of on axis sharpness there is not much in it though if I am honest, at least in mine, it is possible mine is slightly off or one in a bad batch, but I did a careful comparison of these way back in the Heritage 130p, and even also off axis IIRC the 25mm BST you are not gaining much if anything on my 25mm super plossl, for that the TV plossl should come into its own. 

Good luck with whatever you buy, and as Charlic said, if you can try before you buy why not 

[michaeldurban]

Don't rush

I bought the Dual ED's, (BST starguider) 25mm, 15mm and 8mm

They are ok, but you will need a focal extender to get rid of the coma..

Which is prominent at f4.7

If I had to do it again, I would have forked out $30,- more for the ES 82/68 range.

Get a quality eyepiece, you'll thank yourself for it !!!

[cuivenion]

Well I went for the 8mm and the 18mm BST. I thought I'd give them a try as I can always send them back if I'm not happy with them. I might have to get a televue plossl for my birthday much later in the year. To Compare.

[michaeldurban]

....hope you thanked yourself..

let's chat in a few months time...

sigh..

explore scientific..

[Astral Enigma]

Guess I'm having similar questions, being fairly new! I've come to the view that spending more on better eyepieces is best otherwise I'll always be not quite satisfied! But which one(s) is much harder, as in general shops aren't too keen on try-before-you-buy - and eyepieces can be quite a personal thing! 

I've found having a zoom is useful, though just how good (or not) it is, is hard to tell. I have the Opticstar XL but with, for the short term, the possibility of changing it but to a limited set of alternatives. I've also bought a Baader Hyperion 10mm which was highly recommended, but I've only had the chance to use once so far (weather!) and the zoom at around 10mm seemed sharper.

So I'm also now considering whether to invest in (say) a 9mm or 11mm Nagler for good planetary viewing in particular. Any thoughts?

[cuivenion]

....hope you thanked yourself..

let's chat in a few months time...

sigh..

explore scientific..

Feel like I've been told off lol. I'm pretty happy with the BST's, although I'll admit maybe my expectations are lower than others, having only used stock eyepieces beforehand.

[Charic]

......Eyepieces have to be a personal choice, and no one eyepiece works well on every telescope. Folk should somehow try before they buy, at a club or from a friend. Only then will they ever know what's best and to their liking.

I'm totally satisfied with the quality and price of my BST's with the option to have returned any EP that I didn't want or like. I wasn't able to test elsewhere, as I've stated above,  but Sky's The Limit allowed me the option.

I've never tried a Televue? I've no doubt they are great! but how much better they are , over my BST's on my Skyliner f/6 telescope with my eyes, I really don't know?

I doubt spending  hundreds of  pounds (UK) on a Delos , Nagler or Radian  would make  a whole heap of difference on my Celestron Powerseeker 127EQ with its corrector (Barlow) lens in place! That would just have been a waste of money. 

Buying the best EP's out there, is a sure way of self satisfaction, and emptying your wallet quickly, but your eyepiece will only be as good as the telescope providing the image to the focal point. And ultimately how your own eyes see the final image. 

The most expensive eyepieces out there wont do this on their own. The (collimated) telescope  collects the light, forms an image, and ANY quality EP,  if it suits your eyes,  will magnify that image allowing you to see it. 

[michaeldurban]

Cuivenion..

no..not telling you off...but I know exactly what you are thinking..

BST..fair/good reviews, excellent eyepieces, good contrast and

recommended even in a fast dob !

Why pay more ?!!

and then you use them..and the first few weeks you think..hmm..nice..

...then you discover that focusing is quite difficult, and you always feel

you are out of focus because of the coma (at about 40% of the FOV).

And then...you start thinking...damn...

why didn't I save a bit longer, why did I settle..why...why

(facepalm)

[Charic]

michaeldurban,,,,,,,you make it sound as if its the fault of the BST's! and not  the Newtonian which is the root cause?  Do the ES's have built in correctors or do they still need correcting, its all  just more money to try and achieve the same result.

There are many folk on here that use BST's on fast scopes with no reported problems, or at least anything that bothers them.  It will always be a personal thing. You gotta somehow,  try your eyepieces  first , or make do.

[Astral Enigma]

OK, it's time I looked silly.... what IS a BST? I'm sure I'll just say 'oh of course!', but someone please tell me!! Thanks.

[Rustysplit]

BST explorer or starguider. Fine mid range eyepieces.

Do a search for Sky's The Limit, you will see the range there.