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Matching Eyepiece to Scope


GreyRaptor

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Hello all,

I am just getting back into Visual Observing after being away for a few years.  I decided to start small with the scope, a Celestron Inspire 100AZ Refractor.  I am looking to buy a set of Eyepieces and have some questions.  I know they scope has moderate optics, but I am looking to get the most out of it.  The reason I chose this scope was mostly about portability and ease of use as I relearn the night sky from a manual mount refractor.  For eyepieces, I am planning for the long term and I also want a nice eyepiece set to take to the local Astronomy Club observatory and use on their world class equipment.  Are there downsides to using an eyepiece like Tele Vue Nagler or Vixen SSW on a scope that cost less than a single eyepiece? Thank you for any advice.  

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1 hour ago, GreyRaptor said:

 Are there downsides to using an eyepiece like Tele Vue Nagler or Vixen SSW on a scope that cost less than a single eyepiece? Thank you for any advice.  

Yes and no!
 

I greatly admire my BST Starguiders, costing £49 each here in the UK. I also have some TeleVue Delos eyepieces that can cost well over £300 in UK, but to my eyes at present, the images look the same?  but the field of view is wider from the Delos.
For this fact alone the Delos eyepieces maybe an over-kill on my fast/ish scope, although  there are much faster scopes down to f/4 which could benefit further from using a class optic. So on a cost alone, my £49 specials are a treat (good) and work well, the Delos are expensive ( not so good). There are folk who favour Pentax, If TeleVue were not in the equation?

On the good side, if your a brand collector, then knowing that you may own part of the best collection of eyepieces out there, may give you  a sense of better satisfaction, and also with  TeleVue's tested down to f/4 focal ratio, you know your buying a good eyepiece at the outset, that will last a lifetime, and will  work  on just about any scope you dare to purchase, but  to work at their best might be an issue? These are  expensive  eyepieces due to  their  design, material construction and brand name, and for  what their capable of producing, yet I'm unable to distinguish how good so far on my scope?

They say the eyepiece is half the scope or only as good as the scope, either-way, having the most expensive eyepieces is not always necessary at first, and you may not even see or realize their true potential on the 100AZ, but if there was any issue, then knowing your eyepieces are the top dogs, you would have to doubt the telescope itself, or the seeing conditions or your own capability ( your own eyes, and what they can perceive through the eyepieces) but if  you feel that a Nagler is right for you, you buy one, and it suits your requirements,  you may never need to buy another eyepiece again  of the same focal length to improve what your already seeing,  if the likes of TeleView or Pentax are what you desire.

Its finding a balance, what feels right for your situation, and what you can afford or are willing to pay. I don't believe a great eyepiece  alone can make the scope any better, I do believe a scope can let down the performance of an eyepiece as the eyepiece can only work with the image provided by the scope itself. Whatever the eyepiece you decide, it is at the end of the day just a magnifier, hopefully one that is suited to the scope and your eyes.

Eyepiece selection is difficult as there are so many to choose from, and  quite often, its only by trial, with your eyes alone, can/will you decide which is/was best for your needs, building around that system.

I've always wanted to own a Plössl collection? so  from my small collection of Meade, TeleVue and  Revelation, the Revelations have shone through so far, and cheap as chips!
I also wanted to buy a bigger scope, possibly requiring better eyepieces,  and ended up getting the eyepieces first ( Delos) and apart from the wider field of view, still undecided as to what to do next. If I can find some more at the prices I've  paid, its a no brainer, because  they can/will sell no problem, but will I get a chance to view through a 10" or 12" telescope this season, to see how well the Starguiders work, or convert to the Delos if their proven to be much better on the faster scope? I'll just have to wait and see! 

I've just had a thought!  I've not had a chance to view Jupiter since owning my Delos EP's but I can't  imagine Jupiter is going to look any better in a 72° afov eyepiece,  when  even with my 60° BST's, Jupiter looks  oh-so small,  and in all probability one of my  cheapest Plössl's may give a better  result with a tighter field of view in order to best focus on the  great Planet itself, without the surrounding sea of space?

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Hi Grey, welcome to the lounge.

They telescope you mention is an F/6.6 with a 660 mm focal length, 1.25" diagonal

How about a two times Barlow and...

24 mm 68° Explore Scientific for
  28x at a true field of 2.47° and with an exit pupil of 3.6 mm
  55x at 1.24° and 1.8 mm exit pupil barlowed.

16 mm 82° Skywatcher Nirvana / WO Uwan for
  41x at 1.99° true field with a 2.4 mm exit pupil
  83x at 0.99° with a 1.2 mm exit pupil barlowed.

6.5 mm 76° Baader Morpheus for
  102x at a 0.75° true field with a 1.0 mm exit pupil
  203x at 0.37° with a 0.5 mm exit pupil barlowed.

With the 24mm you'd get the widest view a 1.25" diagonal will allow, and with the 6.5 mm barlowed you'll cover the highest magnification the scope can handle (if it is good quality).

Have you also considered a Dobsonian? I may be wrong, but the mount on the Celestron Inspire does not look very effective to me. I think a Dobsonian may offer a better mount and more impressive optics at a similar price.

The eyepieces are just suggestions. Panoptic and Nagler are also quite good!

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What equipment does your club have? And if they have good equipment, don't they have EPs too?

I ask this because larger telescopes are often fitted for 2 inch diameter eyepieces, and although adapters to convert down to 1.25 inch EPs are readily available, you may find that 2 inch EPs give much better wide views for many types of observation especially at lower magnifications. And the larger diameter eyepieces will not be compatible with the Celestron Inspire that you have.

The magnification of EPs is of course dependent on the specific focal length of the telescope. So it's also worth remembering that if you change your telescope or use your EPs on a different telescope belonging to the club, you may get a range of completely different magnifications.

 

 

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7 hours ago, GreyRaptor said:

Are there downsides to using an eyepiece like Tele Vue Nagler or Vixen SSW on a scope that cost less than a single eyepiece?

So, you're asking "Can an eyepiece be too good for its telescope?". No.

On the contrary, when you attach a great eyepiece to an average scope (or when you adjust an average scope), you realize the objective is better than you thought.

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Can a eyepiece be to good for the scope?. In my opinion then the answer can be yes, as I have said it before and I will say it again

Your telescope is only as good as the weakest link in the optical chain.

Is there a point of buying a nagler at over £300 or to the extreme a Ethos at £600 plus to put into a lower priced scope. Then IMO no. As the optical quality of a quality well refined Optics in such eyepieces will not be able to show their true potential in such a set up IMO. Obviously lower priced scope is lower price for a reason. It may be the substance of the build quality. It maybe the precision of the focuser. It may be the quality of the machine and polishing on the optical glass/lens. It may be a combination of all these and other factors. But you cannot expect the same quality of a lower priced scope that you will find in a higher priced premium scope. Therefore if you put a Nagler r ethos in a cheaper priced refractor  you will not get the same quality of view that you will putting a nagler or Ethos in a quality refractor with say Ohara or Scott glass lens in it. As these type of premium optics allow the quality eyepiece to push it's optical limits where a less quality lens will be holding the eyepiece back. You could reverse the situation and say you had a top quality Takahashi refractor. And then went and purchased cheap non well refined eyepieces. Would you be getting the best views out of your Takahashi, then more than likely not. But put a well optically made nagler, ethos , Pentax in the Takahashi and that well made a quality lens of the frac will work well with a well made quantity eyepiece to produce the best quality of view for that particular scope set up. A balanced optical such as this and there is no obvious weak links in the optical chain (as long as the mount or diagonal if used is still of quality and up to the job of this particular set up) 

Obviously if you are in the hobby for the long hall then buying premium eyepieces can be a worthwhile exercise and beneficial. As when you upgrade the scope if you already have premium optical eyepieces then these will obviously stay with you and can be used in your new scope. So eyepieces of high optical quality can be a lifetime investment and therefore it is worth buying from the outset premium eyepieces.

I hope the above is helpful☺ 

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I feel that good quality eyepieces benefit most scopes that they are used with.

I've used Tele Vue and other top quality eyepieces on scopes of varying quality that I've owned since the 1980's and my experience is similar to what Ben says.

I believe that mass produced scopes from the known brand names have pretty good primary mirrors or objectives in them but economies are made in other areas such as the focuser and stock eyepieces provided. Put a decent quality eyepiece into the scope and get the focuser working properly, collimation sorted and you can get excellent performance when the seeing conditions allow.

You don't need to spend big money to get decent eyepieces though. If you can live with a 40/50 degree field of view then there are a number of types around £50 apiece that provide optical performance that matches some much more expensive ones. It's when you get a taste for very wide angle viewing in fast scopes that the bigger investments are required :icon_biggrin:

 

 

 

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5 hours ago, Ben the Ignorant said:

So, you're asking "Can an eyepiece be too good for its telescope?". No.

On the contrary, when you attach a great eyepiece to an average scope (or when you adjust an average scope), you realize the objective is better than you thought.

 

15 minutes ago, John said:

I feel that good quality eyepieces benefit most scopes that they are used with.

I've used Tele Vue and other top quality eyepieces on scopes of varying quality that I've owned since the 1980's and my experience is similar to what Ben says.

I believe that mass produced scopes from the known brand names have pretty good primary mirrors or objectives in them but economies are made in other areas such as the focuser and stock eyepieces provided. Put a decent quality eyepiece into the scope and get the focuser working properly, collimation sorted and you can get excellent performance when the seeing conditions allow.

You don't need to spend big money to get decent eyepieces though. If you can live with a 40/50 degree field of view then there are a number of types around £50 apiece that provide optical performance that matches some much more expensive ones. It's when you get a taste for very wide angle viewing in fast scopes that the bigger investments are required :icon_biggrin:

 

 

 

 

Hi . I agree that a great quality eyepiece (such as the Nagler for example as OP mentioned) will bring out the best to an average scope (as Ben mentioned). But is it really needed or required to spent £300 pounds plus on an eyepiece to get the best out of an average scope. IMO then it's not needed particularly in slower scopes. You can get a great quality Orthos for a fraction of the cost that will provide you with super sharp views IMO(limited on eye relief and fov though). I get the feeling when i hear questions such as above by the OP that sometimes there is the thought that a super expensive eyepiece will transform their scope, when in practice maybe the money would be better spent IMO in getting a higher quality scope to begin with . And spending the money on less expensive eyepiece like quality Orthos , or something like ES or skywatcher Nirvana if you wish more eye relief and fov.

Obviously each to there own way but after my initial scope, I realised that I was not going to spend a vast amount on eyepieces as I felt the money would be better spent on getting two quality scopes IMO. That's why I saves my money and got a OOuk dob and the skywatcher equinox. And then I started to get a better quality eyepiece to benefit IMO the higher quality optics that I now had available to me. So in my opinion instead of getting high quality and expensive eyepiece in an average scope (as Ben mentioned) you would be better off initially putting those many hundreds of pounds extra into a uprated scope, rather than a few very expensive eyepiece. Just my opinion☺

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Another point to consider.  If and when you upgrade your telescope, your eyepiece collection will carry over.  If you've splashed big bucks on a new OTA, it would be nice to not have to replace your so-so entry-level eyepieces with better corrected eyepieces to let it strut its stuff.

One more point to consider.  If you buy premium eyepieces at used prices, you'll generally always be able to get back what you paid for them when you sell them.  You can usually find bargains on entry level eyepieces in the used market because there is practically no used market for them; however, selling them later will be problematic.  Most folks buy them new and then try to sell them when they upgrade to premium eyepieces, but find there are few to no buyers for used entry level eyepieces.  Before I get flamed, I don't consider the Paradigm/Starguider/XCel-LX/HD-60 eyepiece lines to be entry level.  I consider them to be upgrade eyepieces.  They do have a decent used market.  The Nirvana, Morpheus, and ES lines I would consider as bargain premium eyepieces offering 90% or more of the performance of the premium eyepiece lines such as Televue, Pentax, Nikon, etc. at a significantly lower price.

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If you want eyepieces for the long haul then the best quality you can afford is the way to go. In practice I only use my cheap eyepieces in my small scopes as part of the fun of them is not having to worry about ruining any expensive kit. I only get my good eyepieces out with the big scope but this means every session with them is exciting like Christmas!

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