What to do about eyepieces?

[Tinker1947]

Up to and including 24mm, the Hyperions are 1.25" eyepieces with the option to use them directly in a 2" focuser because a portion of their barrel is 2" in diameter. If you remove the 1.25" barrel and the lens set that is within it you get an eyepiece with a focal length of around 21/22 mm but it's not very well corrected with the exception of the 24mm Hyperion does not have a lens set in it's 1.25" barrel.

Baader say there's no optical difference, well thats how i read the reply  " There will be no difference optically. "

[John]

Baader say there's no optical difference, well thats how i read the reply  " There will be no difference optically. "

I think they must be referring to using the eyepiece with the 1.25" barrel and the lower lens set in place but in a 2" drawtube. If you remove the 1.25" barrel / lens set then there is plenty of difference optically, believe me !

[Ags]

I didn't agree with this the comment that the Hyperions are 1.25" EP and removing the first lens group turns them into 2" EP, my Hyperions have never had the first lens group attached these Adapters reside in the boxes with the leather cases, so  rather than just say you're wrong i e-mailed Baader the reply came back as the EP are the same with or with out the first lens group which makes them either a 1.25" or a 2" EP, i class mine as 2" as that how i use them. Copy and paste of the e-mail attached....      

My question 

Text :----------------------------------------------------------------I have several Baader Hyperion Eyepieces and use them in a 2" - 50mm Focuser, is it better to use a 1.25" Focuser and the screw in Adapter does this give a better image when looking through the Eyepiece.Regards Ray

There Reply

There will be no difference optically.

We cannot judge though if you will prefer the handling then and it this might add to the perceived viewing comfort.

Best regards,

Service Team

BAADER PLANETARIUM GMBH

Tinker, take a close look at the 'adapters' you have discarded. They have a lens in them. How can removing this lens have no optical effect?

[Tinker1947]

Well gents i use the hyperions without the adapter and lens always have and trying to use the adapter in a diagonal will result in the Adapter hitting the mirror, so i will continue without the Adapter, my question to Baader asked if i needed to use the Adapter in a 2" Focuser and there reply as i read it says it make no difference so lets leave it at that, i am happy with the views i am getting.....As for the lens it spreads the light cone from the optical system so when fitted to a Hyperion the light spreads out in a very short distance to fill a roughly 48mm wide lens, to my way of thinking this will weaken the images when the same hyperion without the adapter/lens work for me very well...

[Guest]

scroll down to page 3

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

and you will see what happens to your hyperion when you remove the 1.25" nose-piece; you change the focal length!!!!!!!

[Ags]

Tinker, the hyperions do have a problem with 2" diagonals, but a cheap 1.25" adapter for the diagonal would solve this.

[Tinker1947]

Tinker, the hyperions do have a problem with 2" diagonals, but a cheap 1.25" adapter for the diagonal would solve this.

Sorry Ags i don't do cheap this my EP setup, don't have a picture with a Hyperion but i do have those in a Sig, my aim is to beable to swap EP's/DSLR over in the dark without screwing stuff so it all revolves around Click-Locks several of them.....

EP set-up

Without the Focal reducer

DSLR Setup

All changed with a click, the Adapter/lens doesn't figure in my set-up.....

[Ags]

The first lens group of a hyperion not only corrects the field but also, depending on the hyperion in question, acts as a x2 or x3 barlow. I've heard of some people who just bought 1.25" drawtube adapters for each of their 1.25" EPs so they could use all their EPs directly in a 2" diagonal without faffing with adapters in the dark.

[RikM]

.....As for the lens it spreads the light cone from the optical system so when fitted ... the light spreads out in a very short distance to fill a roughly 48mm wide lens, to my way of thinking this will weaken the images...

The shorter Pentax XW's (and Ethos, Delos, Nagler etc.) also use Smyth lens elements in the 1.25" barrels. These are combined Barlow/Field flattner elements that improve the performance of the eyepiece as a whole.

I am sure that with the long F-ratio of your C11 your Hyperions work just fine as they are, but there can't be that much difference in the effective focal length between your 13mm and 17mm (= 22.9 and 21.8mm)? I found that with my 250PX, my 3.5mm Hyperion is pretty good on nights where you can use that much magnification but without the bottom element it showed so much astigmatism as to be (for me) unusable.

[Claire Dymond]

Having just bought the same telescope and having the same questions this thread has been very useful although I did need to take a nap after reading it.

I bought a Luminos 15mm EP and a Luminos Barlow not knowing the Barlow is for a 2" diagonal so I now need to buy a 2" diagonal and hope that it actually fits the telescope because it seems that full knowledge is assumed when buy Astro kit.

Anyone any idea if a 2" Williams diagonal will fit the 2" back of my Celestron or do need to buy another thingamy whatsit with a widget whatisname to actually see something? 

I think I'll leave fitting my Canon DSLR to the telescope for a while.

[John]

The shorter Pentax XW's (and Ethos, Delos, Nagler etc.) also use Smyth lens elements in the 1.25" barrels. These are combined Barlow/Field flattner elements that improve the performance of the eyepiece as a whole.

I am sure that with the long F-ratio of your C11 your Hyperions work just fine as they are, but there can't be that much difference in the effective focal length between your 13mm and 17mm (= 22.9 and 21.8mm)? I found that with my 250PX, my 3.5mm Hyperion is pretty good on nights where you can use that much magnification but without the bottom element it showed so much astigmatism as to be (for me) unusable.

Thats exactly my understanding and experience. 

[Rockrae78]

Some of the 2" diagonals come with a suitable visual back to fit your scope.  Some don't.  The one I bought did (link is on the first or second page I think), but I didn't like it, so I bought a separate Baader click stop visual back (again, link is with the diagonal).

The click stop is useful because there are no screws to turn with cold fingers! Its much easier if you need to reposition the EP to a more suitable angle. 

[Tinker1947]

The Visual back with Click-stop for the C11,14 is a 3.50" unit, luckily when i made a enquiry with FLO Martin had  one on his desk so i grabbed it, on the Hyperion front element i can see now why is required and have ordered one of these from FLO to make using them easier

 http://www.firstlightoptics.com/adaptors/baader-clicklock-2-125-adapter-2956214.html

[jlowdo]

Having just bought the same telescope and having the same questions this thread has been very useful although I did need to take a nap after reading it.

I bought a Luminos 15mm EP and a Luminos Barlow not knowing the Barlow is for a 2" diagonal so I now need to buy a 2" diagonal and hope that it actually fits the telescope because it seems that full knowledge is assumed when buy Astro kit.

Anyone any idea if a 2" Williams diagonal will fit the 2" back of my Celestron or do need to buy another thingamy whatsit with a widget whatisname to actually see something? 

I think I'll leave fitting my Canon DSLR to the telescope for a while.

it's so confusing isn't it???

I feel bad for hijacking my own thread as it has become so much more than i expected.

I have been looking at 2" diagonals all day ( williams looked the best bet ), but, i think i will wait and see, and stick with the 1.25 for a while.

so, i am waiting on the televue 32 that i ordered, and i ordered the 13mm baader hyperion as well today... so that gives me 8, 13, 22, 32 ( and the stock 40 which i guess we should discount )... 

so, for a total noob, i guess i am pretty well setup now...?

I have the tripod set up in the garden now, and popped out for an hour or so, just practising, but it was enjoyable anyway... i need more time, money and EP's i guess ( which hopefully, are coming ) ....

cheers again

James

[John]

I think you are pretty well set up 

I'd give yourself a few more viewing sessions with the stuff you have before investing further. As you are in a good place now, any further purchases are going to be quite expensive to deliver any noticeable improvements so some experience will help such investment goes where it will deliver the most for you 

The 40mm is made redundant more or less by the 32mm plossl which, as well as being of better optical quality, will show you just about as much sky and with a higher magnification which helps darken the background sky.

With your LVW's and the TV plossl, in terms of optical quality you are already at or around the highest levels. Any further investment would be for a wider field of view but you won't improve on the sheer optical performance.

[jlowdo]

thanks John

and this was another £200 over my initial investment, but, as i have said before, i want to cover all bases without breaking the bank. And i am happy to have paid out on the 2 EP's to make sure i don't sit out in the garden thinking it is my lack of equipment that is holding me back. now i have to make myself accountable for my observing! i hope the gear in my sig is now enough to put me in a position to cover all the 'potential' of my little scope... i've said before, that i don't want to be 'all the gear and no idea' but i think, without selling the Mrs jewellery i am now pretty much sorted.. 

so i can spend all my money on cigars and whisky now..... joking

Hoping for clear skies

Cheers

James

[Claire Dymond]

Having just bought the same telescope and having the same questions this thread has been very useful although I did need to take a nap after reading it.

I bought a Luminos 15mm EP and a Luminos Barlow not knowing the Barlow is for a 2" diagonal so I now need to buy a 2" diagonal and hope that it actually fits the telescope because it seems that full knowledge is assumed when buy Astro kit.

Anyone any idea if a 2" Williams diagonal will fit the 2" back of my Celestron or do need to buy another thingamy whatsit with a widget whatisname to actually see something? 

I think I'll leave fitting my Canon DSLR to the telescope for a while.

The answer is yes I do need another adapter for the Williams 2" diagonal to fit the back of my Celestron CPC800, it's called a SCT 2" adapter, bought both on Saturday at The Widesreen Centre in London.