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Finally after a few clear nights I've been able to acquaint myself with my new toy (SW 200P Dob) and have subsequently come to the conclusion that the 10mm EP is borderline terrible. To reassure myself that it wasn't my own judgement, a friend of mine also commented on it and said that I should seek a better EP with a "wider FOV". With that in mind, I've looked around and seen that the Celestron X-Cel seem to offer the widest FOV at the most affordable price.

(1) Can anyone vouch for these EP's. Will they be a significant upgrade on the stock EP's I got with the scope. I have no qualms with the 25mm, but the 10mm just doesn't work for me.

(2) As a student, my budget is quite tight. So with that in mind will the Celestron Omni EP's, or the SW SP Plossl still be an improvement on the stock piece I have? How much more restrictive of FOV are they likely to be in practice, in comparison to the X-Cel range? IS FOV that important on an F6 scope?

(3) Ideally what size EP should I look at for planetary observatory? The 10mm seems to little. Following the guidelines in the sticky EP thread, am I right in thinking a 6-7mm should do the trick?

(4) Following on from the fact I am restricted with budget, I'm considering a Barlow lense, to give me more flexibility with the limited EP's I have. Rather than splash out on a full set. I'm considering the TAL or SW Deluxe, which both work out about £30. Are they any good?

Thanks in advance.

:(

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Hi

The standard SW 10mm EP is indeed terrible. I've got one and it's near useless. I've also got a Celestron Omni 12mm and 6mm, and a 20mm SW SP Plossl. The Omni 12 and SW20 are both pretty good, and miles better than the stock SW, and cheap. The 6mm Omni has such tiny eye relief it's very uncomfortable to use. Incidentally, although the SW25mm is useable, it's not a patch on a 25mm Meade 4000 Plossl, which is also cheap.

I haven;t tried the X Cel or TAL Barlow, so I'll let others comment on them. I have a Revelation Barlow, and that's good.

Personally I'm looking to get a 6mm planetary EP for planetary observing, but haven't got round to it yet. The Omni 12mm in the Barlow works pretty well for now.

Jon

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Thanks. I've heard good things about the BST's, but they only seem to be available in 5mm for higher mag. Will 5mm be too much for my fast scope?

5mm might be pushing it much of the time. They do an 8mm as well though. See this web page (same company as the one on E.Bay):

1.25" Eyepieces

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Thanks for the link(s). So how do these compare optically against the Celestron X-Cel, are they as good quality?

Can someone also please explain the advantages of a 2" EP, if there are any? Do you literally get a bigger image?

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From what I've read I think the BST Explorers are probably as good if not a bit better than the Celestron original X-Cels and nearly as good as the newer X-Cel LS range.

A 2" eyepiece allows you to have a wider field of view than a 1.25" one so they tend to be favoured in the longer focal lengths - longer than 20mm / 25mm or so where people are seeking as wide a view as possible. No benefits otherwise.

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This might not be the case, but generally if you buy named bits like Meade, Celestron they add a bit for there name, so being a bit dearer doesn't always mean there that much if any better. I know nothing about EP's only what has been types in these forums, but i will go for the BST as nobody has shot them down.

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1)... Yes

2)... The skywatcher ultra-wide is a small step-up for £30 ish (66 deg ) but, the LX & hyperions are in a different league for price & quality

3)... 7mm or 9mm in the XL range - 8mm if you go for the BST

4)... Both are ok as 'budget' barlows - the 12mm or 9mm + barlow should work fine in your 'scope - the wider view of the XL with barlow means less nudging

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I'm quite interested in the BST, as they seem reputable on this forum with a similar FOV, but can't seem to find anyone selling the 8mm EP. So, it seems I'll fork out a little extra for the Celestron X-Cel LX 7mm.

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I'm quite interested in the BST, as they seem reputable on this forum with a similar FOV, but can't seem to find anyone selling the 8mm EP. So, it seems I'll fork out a little extra for the Celestron X-Cel LX 7mm.

You can get the full range of BSTs here

1.25" Eyepieces

I have 5,8,12,15 & 18 the only one I've heard is not so good (but no personal experience) is 25mm

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I did a head to head comparison between the BSTs and X-Cel LXs. Result the BSTs are indeed very good, but the LXs were a step sharper with better contrast, and I think a lot of it is probably due to better coatings. Side by side the LXs just seem like a better quality eyepiece.

The BSTs are great value for money, but to put it this way, I don't have any BSTs now, only X-Cel LXs (in this type of eyepiece).

John

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I did a head to head comparison between the BSTs and X-Cel LXs. Result the BSTs are indeed very good, but the LXs were a step sharper with better contrast, and I think a lot of it is probably due to better coatings. Side by side the LXs just seem like a better quality eyepiece.

The BSTs are great value for money, but to put it this way, I don't have any BSTs now, only X-Cel LXs (in this type of eyepiece).

John

Thanks John, that's interesting. There's approx £30 between the EP's, so if there is a noticeable difference in sharpness and contrast then I'll go for the LX.

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As I mentioned the BSTs are very good, and if I hadn't done the head to head comparison I would have been very happy with them. Are the LXs worth that much more....good question. :( However for me it all came down to if I had stuck with the BSTs (and they are great value :o) I woud have felt as if I'd have settled for them instead of getting what I really wanted.

John

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I contacted Alan at skys the limit (BSTs supplier on ebay as well) and asked his advice on what eye piece to upgrade for my new scope He recomended the 8MM BST I took the plunge and WOW the difference between the new 8MM BST and the 10MM EP supplied with the scope when viewing Jupiter was out of this world.(pardon the pun.) I shall now be saving hard to complete the set.

Mick.

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Alan is a nice bloke. He will even let you try a few different eyepiece, buy the one you want and return the others!

My experiences with these types of eyepieces, is there is very little to choose between them, the main difference which could have some bearing is eye relief - the william optics spl have 20mm so good if you have specs but most of the planetary types have good relief - the main advantage over plossl or ortho.

But I have found that none of them are as sharp or have the same light throughput as a good plossl.

andrew

andrew

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  • 2 weeks later...

So after I thought I had settled for the Celestron X-Cel LX, I discover the Baader Hyperion range!!

There is approximately £20 between the EP's, SO are the Baader range worth the extra outlay?

Thanks.

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I've not used the X-Cel LXs but I do have Hyperions and I like them very much. On paper they have a wider field of view, and with the use of fine tuning rings can offer different focal lengths. They also have a screw threads for camera attachment too.

More info here...http://www.baader-planetarium.com/pdf/hyperion_brief_description_e.pdf

My telescope is an F6 200P dob and the Hyperions work well. There have been recent threads discussing their use in faster telescopes and they don't do as well, so if you do have an F5 or faster then you may be better off with other eyepieces.

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Thanks twotter, I actually have the same scope as yourself so good to know they work well with it.

What do you make of the stock 10mm that came with your scope? I've found it very disappointing to be honest.

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A general comment on EP choice.

There are two dangerous "ratchet" effects driving up EP price. The first is visible in this thread:

1) lets go for EP A, it is a clear step up from what I have and affordable at GBP X (with X a variable determined by personal situation (such as when did the missus last buy new shoes;))),

2) oh wait, EP B only costs Y = X + epsilon, that's OK too, and it is a bit better.

3) Next up EP-C, which costs Z = Y + epsilon, and so on.

Before you know it you are in Nagler and Ethos territory, mortgaging the house, divorcing the missus etc :).

The second ratchet effect is that you want to have all your EPs at the same quality as you best EP. Buy a 10mm (or similar) that is clearly better than your 25, and you will want to replace your 25 as well. But the better 25mm is just a notch better than the 10 you got, so you want to get a better one of those, again ending up in Nagler, Ethos, Pentax, or Takahashi territory (see, they are inevitable :D).

The second ratchet effect certainly worked for me, for once I got my TMB Paragon, there was no turning back, as can be seen from my sig.

The important thing to do is look through EPs, not at them. I upgraded kit when I felt bothered by the limits of existing kit (as you are doing now). Compare stuff yourself, and see if you see a real difference. As you gain experience you will start noting more differences, and your demands may grow. If I were to go back to EPs which gave e a lot of joy ten years ago, I would probably see defects I did not notice at that time. That does not mean I should have bought the expensive kit immediately, because I might not have seen the difference. I kept them while I enjoyed them, and once I got a taste for better ones I replaced them.

Good luck making your mind up.

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