Baader Hyperion Eps

[UnderTheRain]

Forgive me if this is a stupid question but are the Baader Hyperion 68's the same focal length when used in either 1.25" or 2" configurations? Is a 17mm for example 17 when used as a 1.25" and 17 when used as a 2"?

Thanks

[brantuk]

There's a full table of ep sizes with combinations of ftr's at the bottom of this page.

Baader Hyperion 8mm 1.25" / 2" Eyepiece | Telescope Accessories | Rother Valley Optics

Hope that helps

[UnderTheRain]

Hi thanks for the link just so I'm reading that correctly with the 1.25" removed all the eps become roughly a 22mm? And adding a 2" filter changes the mm I assume that a 1.25" filter doesn't would that be correct?

Still being new I still haven't got my head around everything yet

[Macavity]

<quickly erases stuff> Ooops, talking to cross purposes. The REMOVAL of the 1.25" nose-piece is different question. The upper section of the Eyepiece will indeed function (somewhat) as a 2" eyepiece of long focal length. A useful stop-gap, rather than a quality 2" eyepiece. You can also change the separation between the top and bottom elements, to achieve other focal lengths. If someone doesn't beat me to it, I'll add the canonical documentation...

http://www.baader-planetarium.com/pdf/hyperion_brief_description_e.pdf

[UnderTheRain]

Thanks that's exactly what I needed to know thank you both

[brantuk]

The ftr's are "fine tuning rings" that alter the focal length of the eyepiece giving you 3 eyepieces in one (as stated above). They are all photo friendly in that you can get the step down ring that attaches to the ep on one side and a T-ring on the other - making it easy to put a dslr camera on the end of it.

[John]

It's worth doing some research on Hyperions and how they work with fast scopes - there may be better options if edge sharpness is important to you.

With the 1.25" nosepiece removed the resulting 22mm will show lots of astigmatism in the outer 25% of the field of view with an F/4.7 scope.

Don't get me wrong, I like Hyperions a lot in scopes slower than F/6 but I'm not convinced they are the best option for £90 apiece in fast scopes.

[umadog]

They work very badly in fast scopes. Astigmatic as hell. There're better eyepieces for the money if you're <f/6.

[M4lcs67]

Apologies for daft question, but can someone tell me what the calculation is for working out if your scope is fast or slow? I am virtually ready to slap some money on the table and get the Baader Hyperions. I have done my research and the results are in.

[Dunkster]

F-ratio = focal length / aperture

Smaller numbers are faster, higher numbers are slower.

Maks are slow Malcspring

[twotter]

My Hyperions are fine in my F6 200P dob so I would expect them to give good views in your 127 Mak

[UnderTheRain]

Well this is my first week with my scope and I still don't really have a clue what I'm doing but I'm getting there slowly. I've got a couple of hyperions because they were recommended. At present I'm not skilled enough to notice any optical deficiencies but I do really like the design and how versitile they are. I'm going to buy the click stop and camera adapters for them I think as they seem like a really neat way to connect cameras. I'm only going to use them as 1.25"s

[brantuk]

Make sure you get the correct step down ring for the zoom - it's a different size to the one for the regular eyepieces.

[AWR]

Apologies for daft question, but can someone tell me what the calculation is for working out if your scope is fast or slow? I am virtually ready to slap some money on the table and get the Baader Hyperions. I have done my research and the results are in.

My 24mm hyperion is lovely in my 127 Mak (=very slow f/11.8), but much less good in my f/5 dob.

Andrew

[Parus major]

I've been looking at these as well. I know they'd be fine in my 150PL F8 but at some stage I will get a 250PDS which is why I'm a little shy in picking them up.

[Macavity]

Agreed re. Hyperions. But what *are* these better eyepieces in faster scopes.

I sense this deserves (yet) another thread... or a forum search maybe?

[John]

I'd have the following candidates on my list:

Vixen NPL's

Celestron X-Cel LX's

GSO or Tele Vue Plossls

Baader Genuine Orthos

William Optics SPL's

Used Skywatcher Nirvana's

BST Explorers

The above have their own quirks and pros and cons of course but they seem to offer excellent light transmission, contrast, sharpness and are reasonably well corrected for use in fast scopes.

I'm sure this list could be extended though

[UnderTheRain]

They work very badly in fast scopes. Astigmatic as hell. There're better eyepieces for the money if you're <f/6.

When you say these are astigmatic as hell how does this manifest itself? As with my limited experience I've no issue focussing the objects in view but I freely admit that I have no frame of reference by which to compare the performance. I've just started out in this adventure called astronomy and I think it may be a while before I understand what makes a difference and why.

[John]

Astigmatism caused by the eyepiece looks a bit like this:

[UnderTheRain]

Ah I see on the edges, I think I'm still too locked onto the middle atm to of noticed but I'll have a look next time I'm out.

Thanks for the diagram

[Tinker1947]

I have a 24mm on order from FLO, with the camera adapter this will be its main use, subject to star trails ect, but will give a viewing report ect.

[UnderTheRain]

Yeah I'll be ordering the adapter for my canon and also with the click lock adapter I think my web cam will also fit right on the end

First Light Optics - Baader Click-Lock 1.25-inch Eyepiece Adapter with T-2 Thread

That adapter looks just the ticket for my Microsoft web cam

[Tinker1947]

My Hyperion-8 24mm arrived couple of days back, this afternoon had some clear skys, around 16:30 Jupiter showed its self and looking through the 24mm gave nice clear bands all 4 moons used the Reverlation 2X barlow and still crisp clear view, compared to the SW 28mm a lot more contrast and sharper view, a bit later looking at Almaar the Hyperion split the 2 stars not a big gap but a clear defined gap, better gap with the barlow still sharp crisp view, the SW 28mm could see the blue but join to the main star, this would be the 24 verses 28mm, happy i brought the lens its appears well built and feels solid, so i'm thinking 13 or 8mm next so far no astigmatism, not sure if it would show more in a more powerful lens (13/8mm) ???

[umadog]

Yes, it looked like what John showed. Maybe worse. I remember that the 13 mm Hyperion looked as bad as the cheapo 3 element "Plossl" that came with my scope at the time. Instead of pin-point stars you see a blur. It's pretty obvious, you don't need lots of eyepiece time to notice it. I switched to Explore Scientific 82 degree eyepieces after that. When on sale, they cost the same as the Hyperions but perform almost as well as a Nagler. Can't complain.

[Tinker1947]

So i for a better quality high powered EP with a FOV not to big but bigger than 50' anybody have one of these or know of them...

First Light Optics - Pentax XF 8.5mm