Buy 1 eyepiece?

[BeerMe]

As I posted elsewhere, I got a 10" Dob (fl 1200mm; f4.7) yesterday and have only the stock 25mm that the guy had (condition unknown as yet but it looks fine to the eye) and a Starguider 7-21mm zoom EP, which is decent for what I paid.

I've only got £60 available to spend right now and since that's about the upper limit that I'd spend on a single EP, I'm happy to go ahead and add something to my collection now, since I really do need it.

Currently, I'm thinking of going for a short focal length EP as we are coming in to summer and the only objects that are going to really show much detail are the planets and moon. 

Thoughts?

[davehawkins]

I'd go for a BST Starguider £49 + postage from First Light optics or if you can pay a bit more a Vixen SLV £79 + postage from FLO.

[valleyman]

+1 for the BST

[BeerMe]

32 minutes ago, davehawkins said:

I'd go for a BST Starguider £49 + postage from First Light optics or if you can pay a bit more a Vixen SLV £79 + postage from FLO.

 

There's a 6mm Vixen SLV that's for sale in here at the moment that's just affordable.   Would that EP work ok in a low focal ratio scope like mine?  I remember reading that there were certain EPs to avoid.

[davehawkins]

4 minutes ago, BeerMe said:

 

There's a 6mm Vixen SLV that's for sale in here at the moment that's just affordable.   Would that EP work ok in a low focal ratio scope like mine?  I remember reading that there were certain EPs to avoid.

I've got the 10 and 15mm SLV's and they work fine in my SW Explorer 200P F5 Newt.

[JOC]

I don't know how it would go in a 10", but if I went out to buy just one of the EP's I have accumulated I think it would the Meade 4000 15mm.  I don't know if that's any use as an observation though.

[Nyctimene]

What about a good quality 2x Barlow?  With it, you could reach mag 342x with your zoom, enough for the usual weather and seeing conditions and for a 10" scope.

Stephan

[ronin]

I would say the 8mm BST Starguider, as you want a bit more magnification then the supplied items. Otherwise the 12mm Starguider

Only coinsidered ones that are new as used means waiting for the right one to appear and then you have to be the person that gets it. Used is good if what you want happens to appear at the right time or you are happy to wait a month or two for something to appear. But if you want one for next week then really it has to be new.

[catburglar]

If you're happy with the quality of the zoom in your new scope, I'd be tempted to go for something around 5mm FL. If the zoom is a bit soft at high power you could do a lot worse than the 6mm SLV mentioned above.

 

Your zoom will get you 170x which is a good 'every night' high magnification for the Jupiter. But you can often go higher on the moon- The 6mm SLV would get you 200x, but that's not much of a step up (if the zoom is good at 170x) , and the 5mm will get you 240x which will be a great Lunar high mag that you'll be able to use frequently.

The BST starguiders get consistently good reports.

[triton1]

+1 for the 8mm starguider

[spaceboy]

I'd go with a used 12mm bst (£35-£40) one in sgl sale section at mo...... and revelation x2 or x2.5 barlow (£15-£25) from astroboot

[BeerMe]

Lots of great suggestions, thanks folks.  I'm definitely leaning towards the idea of something in the 12-15mm range and a decent Barlow to supplement it, for those nights of good seeing when I can push the magnification up a bit.  It would also give me 3.5mm on the short end of the zoom which, if nothing else, would be interesting to see.  342x mag (thanks @Nyctimene) is mind-boggling considering the best I've seen so far is 65x in my Heritage. 

I'm going to have a good look at how these 2 that I have perform on the scope tonight, and make a decision tomorrow on what direction to go with my next buy(s) :-) 

Thanks once again for the input everyone, I'm still open to suggestions. 

[Moonshane]

Do remember that it's not always beneficial to use higher magnification. I'd say that 7mm is about the maximum on a lot of nights with your scope although as suggested on moon / doubles you will probably be able to use more. I have recently been struggling to use more than 100x with my 120ED on Jupiter due to poor local seeing.

[John]

If you get an 8mm BST Starguider you might find that the zoom does not seem so satisfying in the F/4.7 dob

Personally I'd not use a barlow with a low cost zoom in such a scope.

As Shane suggests, those 250x plus magnifications won't be a whole lot of use very often. If money is tight, invest where it will get most use.

[BeerMe]

1 hour ago, John said:

If you get an 8mm BST Starguider you might find that the zoom does not seem so satisfying in the F/4.7 dob

Personally I'd not use a barlow with a low cost zoom in such a scope.

As Shane suggests, those 250x plus magnifications won't be a whole lot of use very often. If money is tight, invest where it will get most use.

Yeah I wouldn't expect to see anything great with a Barlow on the zoom John, and the chief purpose of it would be for the mid-range EP.  There's 4 EPs available as a bundle on fleabay, and 1 of them is an 8mm Starguider  (there's also a 15mm wide view and 25mm and 40mm Celestron Plossls) so I might pop a bid in for that and see if I get it as that would give me a good selection of focal lengths to be starting out with, even if they lack a bit in quality. 

[Littleguy80]

I got the Revelation 2x Barlow off Astroboot recently (£21 with shipping). It has the option of unscrewing the the barlow element and then screwing it directly onto the eyepiece, same as a filter, to give 1.5x magnification. Will give you more options. The BST's barlow well in my opinion

[JOC]

I've got a Skywatcher Delux Barlow - that is also one that screws apart and will also provide a connection to a camera T ring.

[BeerMe]

Thank you all for the suggestions, I've made a couple of purchases from astroboot that I'm happy with.

I've posted before about the gold line eyepieces and astroboot had a Celestron 15mm.  These eyepieces have good reviews at this range, and the 15mm with 66° FOV should provide some nice views for both planetary and DSO targets. 

To supplement this, I've decided to opt for the Celestron 1.5x/2.0x Barlow as suggested above.  Discounting the zoom,  this gives me a range of views from 25mm to 7.5mm.  25-16.6-15-12.5-10-7.5 to be exact.  Lots to keep me interested over the summer :-)

The rest of the funds will go towards a much-needed Rigel/Telrad.

[John]

Good old Astroboot

 

[BeerMe]

4 minutes ago, John said:

Good old Astroboot

 

It's a brilliant site John, just a shame that they don't have the Rigel I'm looking for or they could have had all my funds lol.

Barlows get a bad rep and maybe deservedly so, but I think this is one of those things that I need to try for myself.  It's a fairly inexpensive foray, and my untrained eye will have some fun enjoying different views :-)

[John]

Barlows can be very useful to expand an eyepiece set and also to provide short focal length eyepieces without the very short eye relief that often goes with such eyepieces.

 

[Dave In Vermont]

On the subject of Barlow's, I've said this many times - and still stand by it. To the degree that I've kept a copy of it - which is a 'Cut & Paste' below:

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Poor quality Barlows' can be the worst enemies to the cause for using a Barlow - ever again! A Barlow
adds more glass in the optical-pathway from the primary mirror or lens. A lesser Barlow-Lens not only
can dim the target and bring a loss of clarity - it will magnify any imperfections the eyepiece may have,
or the lens, filter, mirror, etc. So you want a Barlow that becomes as close to invisible itself. Many
would-be Barlow lovers end up buying Barlow's over & over again - looking for 'the one' that has the
least problems, while resisting buying the 'top-priced' Barlow. The TeleVue® Barlows. And a few
others are now right up there, too, but I'll let other folks talk about these. I have personal experience
with the TV's so I'll stick to these here.

The result of buying one mid-cost Barlow, selling it, and trying yet another is either giving-up
altogether. Or having a drawer full of Barlows - collecting dust. Untouched. But after all the
disappointment, buying the TeleVue 2X or 3X seemed throwing more good money - more than the
dust-collecting one's cost - on finding a good Barlow. If it even existed. Until you either get lucky at a
star-party and try a TeleVue® Barlow, or inherit some extra money and buy one. And then it all
changes.....

The TeleVue seems to have vanished - just adding pure magnification without dimming or a loss of
resolution. And the price really wasn't much more money than the mid-line (dusty) Barlows. And if
you'd started with these, you wouldn't have bought another Barlow because you started at the top-end.
The only direction from there is down. I usually hesitate to suggest TeleVue® to folks - especially
recent converts to astronomy and observing as the high-costs of these can appear 'elitist' - but in the
case of Barlow-lenses I make the exception. A little 'green-lettering' in the eyepiece-case is okay to me.
And if you start at the top, what's that 'only direction' thing...? Oh yeah - down. And the price of these
isn't really that much more. Look for sales.

Due to their becoming invisible (almost), I've never a reason not to throw it into my optical-train. And
the TV 'PowerMates' are even better in most observer's opinion. But I won't go there now. Those aren't
a true Barlow.

I hope this saves you some money, and increases your fun!

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That's my view on buying a Barlow. Feel free to ask questions, or throw rocks!

Dave - with very few 'green-letters' in his eyepiece-cases.