The more I read, the further I get from an EP decision

[Stonius]

Hi there,

I've got an 200mm (8") f/6 Saxon Dob. I've had a lot of fun with it. It came with 25mm and 10mm multicoated Plossls. http://www.saxon.com.au/eyepieces/eyepieces-plossl-eyepieces.html

I was thinking maybe I should get a 2x barlow, but as everything in the optical path is only as good as the weakest link, I wonder whether the scope and eyepieces are 'good enough'. Put it this way, no-one's lusting after a Saxon eyepiece. If I were to replace my two eyepieces, I couldn't justify spending $300 on a Pentax XW or a Tele. I could spend maybe $170 AUD max per eyepiece. But since researching, I've found out that multicoated Plossls are a pretty good design and since the ones that came with my scope are about $70 ea, I wonder if the difference would even be all that great?

I've also read that different scope designs create focus planes that are concave / convex to varying degrees, which is why it's important to get an eyepiece that works well with your particular scope design. For example, an EP that works great on a reflector (convex FP) could look terrible on a refractor (concave FP). But as AFAIK, EP manufacturers don't even publish that kind of data. I assume it would also depend on the scopes individual F ratio too

And then factoring in that Barlows can correct optical anomalies of the EP's themselves, I assume that again, it depends on the design of the EP and scope for it to work in harmoniously.

Even if it's best to wait for a bit and save up, I wonder what the second tier EP's are. I typically find that in most things second tier is the best value for money with 95% of the quality at a much better price.

Any thoughts gratefully received. I should also add that I'd like to move towards doing some astrophotography (looking at a skywatcher AltAz/EQ5 mount) so something to keep in mind.

Markus

[MortonH]

Explore Scientific eyepieces offer a substantially wider field than Plossls and the 1.25" models will cost under $200 used. They have good enough correction to perform well in all scope types.

Some others under $200 (used) worth considering would be:

Pentax XF 8.5mm (not so much the 12mm)
Vixen LV, NLV & SLV
William Optics UWAN
Long Perng LER (long eye relief) - also sold under various brands like Orion for a lot more money - buy the cheap versions.

I've owned or used eyepieces from all of these ranges and consider them a step up from standard Plossls.

[glend]

The GSO Superview EP range are well regarded by those that own them, and very cost effective. I have three of them and they get used more than my TV Naglers.

[Stonius]

Thanks for the eyepiece suggestions, keep them coming - I'll definitely look into them. Does anyone have any opinions on barlows? I'm thinking I'd get 2 eyepieces and a 2x Barlow. There seems to be a lot of discussion online regarding eyepieces, but not so much on barlows?

[janoskiss]

Well within your budget I just remembered these 68-degree EPs will work great and are well suited to your scope:
Saxon SWA 13mm (http://www.saxon.com.au/eyepieces/saxon-13mm-1-25-swa-68.html)
Saxon SWA 8mm (http://www.saxon.com.au/eyepieces/saxon-8mm-1-25-swa-68.html)
Get them here: http://astropetes.com.au/accessories.html - for $129 a pop. They perform exceptionally well for the money.

They are basically rebadged Orion Stratus, which are Vixen LVW clones/inspired EPs. (The Baader Hyperion is similar and Celestron have a line as well, I forget what it's called. They are more expensive though.)

I'd recommend only the 13mm and 8mm for your scope. (The others will work fine but they won't be very useful.) These can be barlowed for planetary observation, but that gets a bit awkward because they are so big and also you'll get better planetary performance from a simpler/dedicated-planetary EP design.

To be honest I'm not sure what to recommend but maybe the Skywatcher UWAs on the same page I linked above Astro Pete's could be a good option. They look and sound from the short descriptions as TMB Planetary clones (-- they're poorly named though; ultra wide normally implies 80+ degree FOV. These are 58, same as the TMBs). Skywatcher has not updated their website about them unfortunately. Ask the shop about them. If they're decent then get the 6 and 5 mm; and optionally the 4mm (but that's pushing 300x, which you'll rarely get to use). That would be a great bargain set. Then the only thing you'd need is a wide TFOV. That's harder.

I got a second hand 27mm Panoptic for my 8" f/6 GSO. I also had most of the Stratus EPs and some of the TMBs. They did work very well in that scope.

[AG Hybrid]

Where can one find a Pentax XW for $300? Cosidered a high quality zoom? Baader Hyperion Zoom mark 3 can be had for $399. Gives a well corrected view especially at F6. All the way from 8mm to 24mm. There are plenty of reviews online for it. Just to muddy the waters some more.

[janoskiss]

Forget zooms unless you've tried one and decided you really liked it. Note the FOV decrease with just about all zoom EPs as you zoom out. For a large part what a zoom EP does is just shrink your FOV without showing you more sky. It's not like a camera zoom where you have the same window to look through but the view gets wider or narrower. Typically a 3x magnification zoom (like an 8-24mm) is only 2x TFOV zoom, because you start with 60deg AFOV at 8mm and end with a 40deg AFOV at 24mm. I don't know if those numbers are correct for the Baader but they are fairly typical even for some of the best zoom EPs.

$300 is reasonable for a second hand XW but folks to have those EPs tend to hang onto them.

[ab1963]

The baader mk iii 8-24mm starts at around 68 deg at 8mm and drops to around 50 deg at 24mm,and it is said the mk ii is around 72 deg at 8mm and around 52 deg at 24mm

[AG Hybrid]

So you haven't used a Baader zoom and just assuming its bad? But, then you recommend a clone of a clone. Yeah k.:hi:

[janoskiss]

I'm just telling you how zoom EPs work in general: wider FOV at high powers, narrower FOV at low powers. Hence the FL range does not cover as much of a range in terms of TFOV as it superficially might imply, hmkay. :P

And I did not say it's bad, just that don't buy it before you try it.

[AG Hybrid]

I'll admit they aren't for everybody. However, for versatility they can't be beaten for obvious reasons. But, they do produce a useful side effect. You can find your favorite magnifications in your scopes and from there plan your next purchases of premium eyepieces at those same focal lengths. And you know what magnifications will be useful because you already have experience with them.
That being said I enjoy my Baader zoom and I've yet to have anyone object using it in my 12" at least. I let them use it in their scopes and they seem to enjoy the ease of adjustments. But, the Baader zoom is very good. Wouldn't recommend any of the generic cheaper ones.

[ab1963]

I am with you Adrian i think the Baader zoom is great whatever way you look at it and is my most used eyepiece , have just bought a 2.5x powermate to use it at higher mags , i would think that it would be beneficial for anyone to have whatever scope,still sharp as a tack at f5.9 but never used it in a faster scope than that

[AG Hybrid]

Yeah I use it with a coma corrector.

[janoskiss]

Sorry I misunderstood you. I did not realise you had one. I thought you were asking where to get an XW for $300, and failing that you are considering getting the Baader zoom.

Your avatar is rather distracting I must say. My brain mostly subconsciously put the headbanging avatar and "Where can one find a Pentax XW for $300?" together and immediately jumped to the conclusion you said: "Desperately seeking XW for $300". :lol:

[AG Hybrid]

I work in IT. That's me with a client on the phone.

[janoskiss]

That makes perfect sense.

... meanwhile your post made me read some reviews/discussions on the Baader Zoom 3 and most people are indeed singing its praises. The 68-50 (sometimes 70-52) degree FOV is probably a bit overstated; nevertheless it sounds like a great bang-for-buck and very versatile zoom EP.

[astro_nutt]

Hi Markus. Just a thought regarding Barlow lenses. I use a Bintel 2 inch - 1 1/4 inch 2X barlow and find it does the job with a range of EP's.
Another thought is to visit a star party and research the what EPs the owners are using and see for yourself. You'll be able to make a better judgement in what would work for you.
I hope this helps.
Cheers1