Baader Hyperion 8mm or Pentax XL7...?

niko · #1 21-01-2014, 09:51 AM

Seeking some advice from the visual dudes amongst us. If you had to choose between either the Baader Hyperion 8mm or the Pentax XL 7 eyepieces which one would you pick...?

I have the opportunity to get one of these and wonder, in your experience, which one you'd go for.

many thanks

Nick

Wavytone · #2 21-01-2014, 02:09 PM

Easy - the Pentax has much better correction.

Profiler (Profiler) · #3 21-01-2014, 02:44 PM

Keeping in mind the Pentax XL is the predecessor to the current Pentax XW range I would automatically state the XW as easily the better eyepiece. Unfortunately, I don't have any personal experience with the XLs but they too have a reputation as excellent eyepieces in their own right and not far behind their current incarnation (i.e. the XW range). Consequently, I would again lean towards the XL.

From my understanding the Baader Hyperions are the 'poor-mans' 68' widefield which represent fantastic bang for your buck all things considered. However, you buy the Baader when you can't actually afford a Vixen LVW or Pentax XW.

My 2 cents worth at least

niko · #4 21-01-2014, 04:52 PM

thanks crew

mental4astro (Alexander) · #5 21-01-2014, 06:04 PM

Nick, what scope sre you intending to use the EP in?

Hyperions are made for use in SCTs & Maks. They do very poorly in Newt's, except for the 5mm.

Pentax are also problematic in different scopes - not all focal lengths do well in all scopes. Some do better in Newt's, others in SCTs.

I don't give blanket "thumbs up" just because of a brand. It's not that easy. Wavy, you know better than that...

Best thing to do, read as many reviews on the eyepieces you are interested in, being critical of the scope the EP is being used in so it is the same as yours. I for one DO NOT like my Pentax 10mm XW. Yes it is fine in my Newts, but it is crap in my C8. I've also owned 5 different Hyperions, thinking that they are good in Newts. What I didn't read carefully enough was all the positive reviews were from SCTs. The only one that is good in Newts like I said earlier is the 5mm, & it is also excellent in my C8, & is the only Hyperion that remains in my kit.

So take your pick - blanket thumbs up, or a bit more reading...

David Niven (David Niven) · #6 21-01-2014, 06:08 PM

Why not consider the Pentax XF8.5?
It is a gem of an eyepiece.

niko · #7 21-01-2014, 08:06 PM

Thanks again fellas

I will only be using it with a 12" dob

Profiler (Profiler) · #8 21-01-2014, 09:00 PM

Hi Alex

While you certainly make valid points in the context of eyepiece selection/critique in general I think the actual question was in a finite pick of having to choose between either a 8mm Hyperion or a 7mm Pentax XL which one would "you pick" ('You' - directed to IIS members). Based upon your comments it sounds like you would be congruent with the rest of us that the XL would most likely be the pick over the 8mm Hyperion.

On another note have you tried any of the higher FL XWs (eg 14, 20)? I would be interested to hear your thoughts as others often seem to criticise the 20mm XW but I find it to be excellent and certainly better than a 19mm Pan (on refractors which I use)

mental4astro (Alexander) · #9 21-01-2014, 09:31 PM

Profiler,

I can't comment on the XL Pentax in question as I have neither used one, nor read up on it. So no, I'm not in consensus with the Pentax. I'm only saying to make the best choice, read up on people's experiences with this XL in Newtonians - that's what I should have done more critically when reading up on the Hyperions. What I do agree with is the 8mm is NOT a good match with Newtonians. Very nice in an SCT.

I should also note that I knew a whole lot less about eyepieces when looking into the Hyperions than I do now - Wavytone has helped me a great deal with understanding focal plains of scopes vs eyepiece compatability.

Now, I've quickly looked up the AFOV of the XL's - the same as the Vixen LVW's at 65deg. What I can recommend in the same AFOV range as the XL's and Hyperions is the 8mm LVW. It is not only excellent in Newtonians, it is probably the most comfortable eyepiece I have used with next to no eyestrain noted with extended periods of use. The only other eyepiece I've found to cause as little eye strain is the Celestron Ultima LX 8mm, but this eyepiece is only good in SCTs, not Newtonians. All the LVW's perform really, really well in not just Newt's, but all other scope designs (other than the 30mm, and Vixen notes this by giving the 30mm LVW a totally different appearance) - this is something which very, very, VERY few eyepiece ranges can do.

With respects to the XW's, my direct experience is only with the 10mm. Otherwise it is only what I've read. From this, the XW's may be nice, in the scopes that there is an optical match with, or they are no better than any other cheapie. From what I recall, the 14mm is poor in Newtonians. So are a couple of others, but I can't remember which. If you are keen on Pentax EPs, you do need to find out which are best suited to the scope you use - goes with any EP to find the best optical match.

AG Hybrid (Adrian) · #10 21-01-2014, 11:15 PM

14mm and above Pentax XW perform worst in fast Newtonian's due to induced field curvature added by a different lense design from the 10mm and below. A paracorr will reduce or eliminate that problem though due to it correcting the field by flattening it. If you already have a paracorr than its alright. In my opinion its not particularly good value if you need to purchase a paracorr with a Pentax XW 14mm or above with the intention of using it to clean up the views in the eyepiece.

To answer the OP. I would go with the Pentax 7mm since that's the only option given. You should hunt for a Vixen LVW 8mm. I looked through one. I think it belonged to Wavy or was it Geoff? Don't remember. The view however was superb in my 12". I tried a Hyperion 8mm in my 12" and I didn't like to be honest.

Your mileage may vary however.

ausastronomer (John Bambury) · #11 22-01-2014, 03:27 PM

Quote:

Originally Posted by niko

Seeking some advice from the visual dudes amongst us. If you had to choose between either the Baader Hyperion 8mm or the Pentax XL 7 eyepieces which one would you pick...?

I have the opportunity to get one of these and wonder, in your experience, which one you'd go for.

many thanks

Nick

Hi Nick,

In regard to these 2 specific eyepieces (7mm Pentax XL and 8mm Baader Hyperion) when used in your particular scope, which I believe is a 12"/F5 Newtonian, the 7mm Pentax XL will be clearly superior, with or without a paracorr. Wavytone's advice was spot on in this case.

How do we define "clearly superior"? Well, lets just say that in that particular telescope the 7mm Pentax XL performs like the premium eyepiece it is; and the 8mm Baader Hyperion performs like the lower to mid priced eyepiece that it is and the differences in contrast, EOF correction, lateral colour and light throughput are noticeable. The differences would be less noticeable to a new observer.

Some other good options to consider at this focal length which are all superior IMO to the 8mm Baader Hyperion, are the 8mm Vixen LVW, a 2nd hand 8mm Televue Radian and the 8.5mm Pentax XF.

The 7mm Pentax XW and the 8mm TV Delos are both excellent but expensive and don't gain a lot over the 7mm Pentax XL, or the 8mm Vixen LVW, 8mm TV Radian or the 8.5mm Pentax XF.

Cheers,
John B

Camelopardalis (Dunk) · #12 22-01-2014, 08:14 PM

The Hyperion have a good rep for slow scopes...so go Pentax for a newt!

Regarding different behaviours... the longer FL XW (2") make for great viewing in my Edge HD but the 10 and 7 are tricky for eye placement.

Wavytone · #13 22-01-2014, 08:56 PM

Quote:

Originally Posted by AG Hybrid

You should hunt for a Vixen LVW 8mm. I looked through one. I think it belonged to Wavy or was it Geoff?

Probably mine, I have a set of LVWs...sold the rest.

Profiler (Profiler) · #14 22-01-2014, 10:07 PM

Sounds like everyone is in favour of the XL over the Hyperion

gb_astro · #15 23-01-2014, 09:14 AM

Quote:

Originally Posted by niko

Seeking some advice from the visual dudes amongst us. If you had to choose between either the Baader Hyperion 8mm or the Pentax XL 7 eyepieces which one would you pick...?

I have the opportunity to get one of these and wonder, in your experience, which one you'd go for.

many thanks

Nick

Never used the Hyperion 8mm but I do have the Pentax XL7 and no problems in my f4.5 dob.
Also very comfortable to use.

gb.

niko · #16 23-01-2014, 09:39 AM

thanks again guys for all the considered comments!

Fox · #17 24-01-2014, 01:04 AM

Niko, there's little contest here, go for the Pentax. I have right now a Pentax XW 7mm and Orion Stratus 8mm - which would not be too far from the Pentax XL 7mm and Hyperion 8mm for comparison. Couldn't put it more better than John B said already, the Pentax is 'far superior' (esp in fast scopes) in terms of contrast, edge correction and light throughput. But hey, the Pentax is what - about 3 to 4 times the price of the Orion! - so you get what you pay for.

Now, to be fair, for the beginner/less critical observer on a budget, IMHO the Hyperions and Stratus line are a nice eyepiece for what they offer - 65 deg FOV, long eye relief, large eye lens, and comfortable viewing. I have three close friends who each started out with a Skywatcher SWED80 refractor, and they love their Orion Stratus EP's. I didn't want them starting out with 50 deg bottom rung Plossls. I reckon if they want something better and more exotic, like ES, Televue, Pentax etc. then that can come later, if/when they can appreciate and justify the costs involved.

mental4astro (Alexander) · #18 24-01-2014, 09:12 AM

Looks like the 7mm XL is a great match with Newtonians

. The best references are those where the EP in question has been used in the scope design you are using, like gb wrote.

Don't dish Hyperions (Stratus - same EP) outright. Like many EPs, they are very scope specific. They are best matched with SCTs, with the only exception being the 5mm which is actually very good in Newts. I'm sure there are better performers in SCTs than these, but they are good value from the used market if the purse strings are tight.

Profiler (Profiler) · #19 24-01-2014, 12:40 PM

Quote:

Originally Posted by Profiler

Keeping in mind the Pentax XL is the predecessor to the current Pentax XW range I would automatically state the XW as easily the better eyepiece. Unfortunately, I don't have any personal experience with the XLs but they too have a reputation as excellent eyepieces in their own right and not far behind their current incarnation (i.e. the XW range). Consequently, I would again lean towards the XL.

From my understanding the Baader Hyperions are the 'poor-mans' 68' widefield which represent fantastic bang for your buck all things considered. However, you buy the Baader when you can't actually afford a Vixen LVW or Pentax XW.

My 2 cents worth at least

Sounds like everyone agrees with this now

Wavytone · #20 24-01-2014, 05:04 PM

Fox,

The Orion Stratus eyepieces are an inferior copy of the Vixen LVWs. Some years ago Orion was rebranding vixen LVWs however this ceased quickly for some reason. After that Orion tried to go it alone using the outer shells but without Vixen lenses - presumably some Chinese outfit making knockoffs that were less than perfect copies - under the 'Stratus' label.

Trying to compete at the low end of the market may have been the plan...