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View Full Version here: : Best EPs for 10' DOB?


Andirus
07-11-2006, 08:56 PM
Hello to all,

Permission To Come Aboard! :screwy: New Amateur about to get his first scope.

I've done my research and am going to buy a 10" Dob (lightbridge). I thought the hard part was over, but wait... eyepieces! OMG!

Can someone please give me some advice as to what i should be looking for here. My budget is tight - probably no more than 200-300 AUD to spend.

Is there an eyepiece guide? etc etc

Many thanks

Andy

janoskiss
07-11-2006, 09:13 PM
Welcome aboard Andy! :hi:

Sorry, no eyepiece guide. I'd go for (negotiate with dealer for) a comprehensive set of GSO plossls down to 12 or maybe 9mm, i.e. 32, 20, 15, and 12mm, and a 2x barlow: Orion Deluxe 1.25" (probably best value but hard to come by) or Shorty Plus (actually 2.2-2.3x) or better but dearer Televue 2x. Any leftover change, spend on Cheshire style collimating tool, Telrad, red torch, charts/guides. (Southern Sky Guide is a great starter and a bargain.)

Binos 7-10x power, 40-50mm aperture are also a must have.

wavelandscott
07-11-2006, 09:23 PM
Welcome aboard!

I'll answer your question "basically" and then leave specific recommendations to others...

I'll also recommend some reading on the Televue website...http://www.televue.com

Yes, I know most their gear will fall outside of your specified price range but the advice is still solid (I think)...The article about "Choosing an eyepeice" and the other article about "Eyepeice choices for a small dobsonian" I think are worth reading...while 10 inch is not necessarily "small" I still think the article makes some sense.

Here is my two cents...I'd recommend getting a few better quality eyepieces instead of a whole bunch of less expensive ones. Quality holds it's value if/when you decide to exit the hobby or trade gear...also if you enjoy it for a lifetime it is still money well spent and you get a lifetime of enjoyment out of some quality stuff...I tend to save and get one "high quality" eyepiece at a time...but that just is me.

Numero uno recommendation is to encourage you to get a good chesire collimation eyepiece...don't mess with lasers for a while...a good chesire will last forever and you will use it everytime you set your scope up...

In general, I'd recommend getting 3 eyepeices...a low power (50x magnification), a medium power (around 100x) and a high power (175x eyepiece)...

However, first up I'd encourage you to get your scope out with whatever eyepeice(s) come with it and use it for a while before spending any money on any additional eyepeices...

I'd strongly encourage you to meet up with others in an Astro Society (join one if you are not a member) or hook up with some other IIS folks and look through their eyepeices and try them in your scope...most people are happy to share...once you know what you like then shop away...but remember, you can not beat trying it before you buy it.

Best of Luck and Clear Skies!

casstony
07-11-2006, 10:50 PM
Hi Andy,
loads of reading about eyepieces at this link http://www.astrosurf.org/luxorion/reports-epsuggestions7.htm
You could just buy one or two cheap GSO plossls to give some other magnifications, then save for the eyepieces you really want.

Gargoyle_Steve
08-11-2006, 12:48 AM
Well having owned a 10" dob for the last 7 months I can definitely recommend the Orion Stratus (price under $200 if you shop around) or the near identical Baader Hyperion range (about $210 to $260) - both "brands" come in the exact same sizes (3.5, 5, 8, 13, 17, 21) but I would recommend the 13mm as a great all round size and VERY useful! These ep's have a 68 apparent field of view, which is somewhat wider than a normal plossl. They represent very good quality at the price and there is little that compare with them at any similar price. (and if you read my sig down below you'll see I own 3 of the various sizes : 8mm, 13mm and 17mm)

As a recent beginner myself I would also suggest something very wide field, in order to help you find objects, and also to give a nice "wide field" perspective which is sometimes essential to really appreciate ertain nebulae, clusters, etc. I have a "cheapy" 30mm 80 Ultra Wide Angle (2" barrel) eyepiece but you may find you get some kind of 30, 32mm wide angle ep with your scope, in which case that will probably keep you going for some time.

Good luck with your new scope anyway, and if you feel like meeting a bunch of us in the Sunshine Coast hinterland for a viewing night, and a test out of some ep's, etc, before buying come along to a night at AstroRons place near Kenilworth (see here (http://www.iceinspace.com.au/forum/showthread.php?t=14710) for details, and here for the map (http://www.iceinspace.com.au/forum/showthread.php?t=8808)) ... next night is next new moon, Saturday 18th November. You'd be more than welcome I assure you and people often do come along from various parts of Brisbane as well as the Coast, and there's room to stay overnight if you want.


Cheers!

Steve

jaramillo
08-11-2006, 02:30 AM
Hi Andy,

with f/5 you own a fast optical system that requires well corrected eyepieces. If I were you, I first would buy one eyepiece of good quality and complete the ep collection successively. My recommendation:

-- 5-8mm Speers Waler Zoom (new series coming soon) with >80 FOV for high magnification

-- 13mm Hyperion with 68 FOV in the mid mag range (gives you about 2mm exit pupil, very good for most deep sky observations)

-- 22mm LVW (65 FOV) for low mag, one of the best corrected eyepieces for fast instruments (in my opinion)

-- A low power ep for finding objects, the most expensive part for owners of fast optical systems, in the 27mm to 35mm range (depending on night sky quality).

Just my 2 cents:shrug:

iceman
08-11-2006, 05:58 AM
For planetary/lunar views I can recommend the Burgess TMB planetary series - I own the 5mm version and like it a lot. Sharp most of the way across the field, excellent eye relief and a big eye lens. Very comfortable to use, and only ~$150.

GrahamL
08-11-2006, 06:08 AM
I find a 27mm and 13 mm cover most of my needs.. what does the lightbridge come with ?

Andirus
08-11-2006, 06:55 AM
Gentlemen,

Thanks to you all for your replies - that's certainly helped clarify what i need to do, and I'll take all your comments on board.

NightStalker - thanks for invite - that weekend will be no good, but I will certainly take you up on another session.

The Lightbridge 10" Deluxe comes with a Meade 26mm QX, so how about a Barlow, 40mm, and 15mm - will that cover my bases?

Any opinions on Bintel EPs?

casstony
08-11-2006, 10:29 AM
The 40mm is no good for your scope as the circle of light striking your eye will be wider than your pupil - you need to stick with 30mm and shorter focal lengths, maybe 35mm at the most. The 15mm gives a very useful magnification of 83X.

ving
08-11-2006, 10:41 AM
how about a 15mm and say 7mm. the 15 will give you a mid powr and 7 for planets and doubles. your 26mm is good enough for low power. for $300 you might be able to get 2 televue plossls or if not 2 meade seies 4000 plossls at least which are better than the ones offered by GSO

more importantly, welcome aboard :)
:hi:

janoskiss
08-11-2006, 11:04 AM
Yes, what Tony said. I'd trade the QX for plossls or maybe a 30mm Superview (although SV is not great at f/5 either), but if that's not an option, you might as well keep the QX for a while as your longest focal length finder EP and add a 15 and 10-11mm plossl and a barlow to round out the collection. As you only have $200-300 to spend, you are best off spending any change on other accessories already mentioned... oh, and a right-angle finder to save you some pain in the neck (but only if you also get a 1x finder like the Telrad).


barlowing a 15mm plossl would be better option IMO than a 7mm plossl.

I think you underestimate the GSOs (or overestimate the Meades).

ving
08-11-2006, 11:16 AM
oi! dont go around quoting me mister!!! :P

only a good barlow will not degrade the views given thu an eyepiece. so rather than getting a cheap barlow and whacking the 15mm in there it would perhaps be better to either buy a good barlow and blow the budget or get a 7mm ep?

i have GSOs steve :) the japanese made 4000 (not the current ones) would i believe blow GSOs out of the water. they can be found for a reasonable price i believe?

stephenmcnelley
08-11-2006, 11:18 AM
Hi Andirus, considering your stated budget of up to $300, a few of the larger GSO superviews and a barlow might get you by for a short while with a 10" dob.

Alternately you could think longer term and buy something like a 17mm Hyperion/Stratus and a decent 2x barlow like an Orion shorty plus and effectively have two respectable magnification ranges as the barlowed 17mm is of course similar to an 8mm EP, but with easier focusing properties and eye relief.
It doesnt sound like much but just one good EP and a barlow will take you a long way into space without visual disapointments and you will still want to use them long into the future.
Have fun deciding.

janoskiss
08-11-2006, 11:29 AM
7mm plossl is painful to use IMO, because of short eye relief and pinhole sized lens. A barlow will be useful with multiple EPs, so it's a good investment. You can get a good one for $99: Orion Deluxe 1.25", FMC Japanese barlow, with internal baffle like its bigger 2" brother. Try Sirius Optics.

Vingo, Re 4000 plossls, well, you did not say before you meant the old Japanese ones. :P The current 4000s are fairly ordinary multi-coated Chinese plossls. GSOs are better.

ving
08-11-2006, 11:44 AM
i use a 7mm. i have no problems with it :confused:
each to thier own :P

JimmyH155
08-11-2006, 11:49 AM
I have a 12 inch Lightbridge and I will thoroughly agree that you wont do any better than getting a Hyperion 13mm. I use it all the time. I also have an 8mm Hyperion - they are huge:) Also that 26mm Meade QX that comes with the scope IMO is absolutely great and just try it out on large open clusters. I call it my "Cluster buster". Yes, you will need a Cheshire eyepiece for collimating. They are about $75 I think:D

stephenmcnelley
08-11-2006, 12:12 PM
Collimating with a film canister will save you $$ give you skills and works well with practice-very satisfying.

Has anyone tried the Stratus EP's under 8mm ? The 8 is pretty large and has a razor adjustment point for focusing with even a good focuser. Is the 5mm for instance even more so?


Oh the 17mm Hyp/stratus in a 10" Newt gives a great viewing arc for nebula and clusters of all sizes, the 13mm is cutting them down in size a bit and you lose some outer features.

In retrospect i thought i should edit that last bit by saying that the 13mm barlowed is a better planetary EP giving a nice 192X magnification in a 10" f5 dob, the 17 mm only gives 147X barlowed but is still nice for high res. planetary viewing.

janoskiss
08-11-2006, 02:35 PM
All depends on your observing habits. IMO, there are only a handful of objects that the 17mm would be more useful on than the 13mm Hyperion/Stratus. 13mm is great for deep sky and barlowed it's great for planets. More detail than the 17mm. The 21mm would make a good companion to the 13mm for framing some of the bigger objects. But none of these realistically fit the budget of $200-300 given accessories needed besides EPs. Did I mention Telrad! :jump2: Film canister collimation is feasible but masochistic IMO. :P

GrahamL
08-11-2006, 08:04 PM
think you have a wire crossed andy ?:)

Grab a telrad like steve mentions they are a great tool

Nordo
09-11-2006, 09:18 AM
Andy
I've only been viewing for a few months, and in that time have tried to learn as much as I can about eyepieces.
I believe your priorities should be:
1. Buy (or make) a collimator and learn how to use it.
2. Buy a Telrad and star charts.
3. Buy a quality barlow such as an Orion Deluxe 2x ($100 for 1.25"; $200 for 2")
4. Depending on your viewing preferences, buy a 8mm TMB ($135) for planetary , and/or 13mm Orion Status ($199) for DSOs.

Unless your constantly trying to find perfection, all of these purchases should satisfy your viewing pleasure for many years. Obviously as you increase your viewing experiences, you will find what will be the best EPs to fill in the gaps, but your existing low power EPs will do for initially finding objects.
:welcome:
PS Keep watching the post in the Star Parties forum for parties at Cambroon. Great bunch of guys, and a wealth of knowledge. Not to mention a large collection of EPs which most are more than willing to let you try:) .