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100° eyepieces so why have so many?


spaceboy

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I thought it may make for a good topic.

Did it not all start of with eyepieces and something like 30° FOV back in the day? I can see the reasoning behind having two dozen eyepieces with such a tight FOV. Improvements upon improvements until All Nagler paved the way with the MKI 82° Naglers.

Just one of these eyepiece could cover a similar FOV of two 40° orthoscopics or 50° plossl. The astronomer could now increase his OR her magnification with out loosing the FOV thanks to this new spacewalk experience. In addition this meant less time swapping out eyepieces to fit things in as one eyepiece could now do the job of two. While the gains meant you only required one Nagler over two similar focal length plossl the MKI were large and often heavy eyepieces so no real gain was felt in the hand while carrying your eyepiece case across a dark field in the middle of rural Britian. 

This was soon to be addressed with the slimmed down T5 and later near anorexic in comparisson T6's. So finally we had almost the best of both worlds. A large FOV in a compact package meaning the old box rammed full of plossl could be shipped off to eBay heaven. A 7 or 9mm Nagler replaced a 9,10 & 12mm plossl, the 13mm Nagler replaced the 13, 15 & 18mm plossl and the 20mm replaced the 20, 25 & 32mm. Other than the need to compensate for poor seeing in the shorter focal lengths this meant that an eyepiece collection could now be culled  down to maybe 3-9 eyepieces over the previous 9-15.

Enter the 100° eyepiece. While not doubling up on the job of a Nagler with only an 18° FOV advantage, the Ethos none the less covers a huge expanse of sky. Offered these days in a variety of focal lengths to suit most telescopes the astronomer again had the opportunity to spend more time at the eyepiece observing more of the night sky than previously allowed.

Now anyone who has a 100° eyepiece will no matter what the brand know these things are no lightweights. While there advantages in some cases are more than their FOV alone I have seen more and more astronomers fill their eyepiece cases to bursting point with 100° eyepieces. Where I may see the advantage of a 100° over say 2 or even 3 plossl it is then lost to the space and weight taken up carrying them.

Now I don't want anyone to think I am in anyway putting down 100° eyepieces as the views they offer are immersive and quite frankly addictive. I own 100° eyepieces myself and other than their weight and physical size I can't knock them. Yes they can be a pain when swapping focal lengths as balancing is often critical. They also demand your full attention when in use as gravity can take hold if your heavy ep if any thumbscrews aren't buttoned up. All that aside they bring a whole new dimensions to your viewing experience impossible to be had in the 40° - 50° eyepiece.

While I have attempted to offer a brief glimpse to the advantages and disadvantage a wide FOV eyepiece brings it now leads me to my topic question.  When you consider for many years the humble 50° plossl served so may so well despite the small FOV why now have so many 100° eyepieces? A box full of every focal length Ethos, ES100 or myriads must weigh a ton? Are the FOV of say the 17 & 21mm etho very similar given the cost involved owning the 2 ? Like wise with the 13 & 17mm? The 8mm & shorter I understand magnification can begin to play a role depending on seeing so while FOV may be similar there is no saying the views will be. Is a night still spent swapping out one focal length for another when you have so many to choose from? Or do you find that FOV that fits the DSO's being observed and stick with the one ep all night? In my experience the latter seems to be the case. Other than some of the much larger clusters or Nebula most objects seem to accommodate very similar FOV. While the magnification can be pushed on some nebula to release more finer detail most clusters gain nothing by this. 

I'm totally open to money being no object and if you can why not. I also appreciate if you only have one hobby what else is there to give up 40 hours of your week for if not to buy the things that improve the other 128 hours. I guess due to costs involved owning a complete collection of 100° eyepieces this is going to get a limited responce but I am sure there are others already bitten by the bug that see their current collection growing to a set when funds permit.

Please note this thread isn't reserved for ethos owners only as I am aware that there are ever increasing selection of 100° eyepieces available to us these days. It is also not directed towards any single brand collection but more so to collections that consist of several 100° eyepiece where it could easily be reduced in number but still cover most needs.

 

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I think the short answer is 'collectionosis'. People like to collect and always will. Usually having different scopes is how we justify excessive eyepiece collections but in reality what you need and what you want are rarely equal.

Even Televue I think, suggested that a group of three Ethos would suit pretty much every scenario.

 

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as you say you can slim it down, but as shane says as well people like collecting things. i used to have in my ep case a full set of bgo,s a 31,22,16,7 naglers and a 5mm pentax, sold them all except the 5mm pentax and replaced them with 3 ethos and a pm an have all bases covered

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I only have 6 Ethos and the 31 Nagler. They serve 5 scopes now from 663mm to 1590mm focal length. Don't know why I also have 4 Pentax XW's, a box of BST's and Maxvisions and a Nagler 2-4 zoom :icon_scratch:

Perhaps it's because I like using nice eyepieces :icon_biggrin:

I could rationalise and run a cut down set plus perhaps a Powermate but I'm sure I'd miss whatever I'd got rid of :undecided:

I'm doing without the 17mm and 10mm Ethos which many say are the best ones in the range so there is some sacrifice there :angel12:

It's a hobby and supposed to be fun rather than ruthlessly logical I feel :icon_biggrin:

 

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I think you are right that certain 100 degree eyepieces duplicate each other to some extent.  For instance, I find that with my 4 focal length scopes, having the 13mm and 21mm Ethos basically make the 17mm redundant.  It doesn't really give me anything I don't have (though i could do with something around the 15-16mm area for my SCT to generate about x150 for planetary).

HOWEVER, I do find that the 4.7, 6, 8, 13 and 21 all do non-overlapping jobs in any given scope (other than the ED80 which only needs half of these).  This is mostly because I need the different focal lengths to achieve different magnifications, particularly to get the best mag depending on the object and seeing conditions.  I actually would like to add a 10mm for this reason - it would generate a x95 mag and just over a degree of field in two of my scopes.

Also, I do use more than one scope at a time.  I typically have 2 to 3 up on my Ercole Giro simultaneously.  I actually found that the 21mm is so useful that I wanted two.  I didn't buy two as the price would be bonkers, but instead I bought an ES 100 degree 20mm, which is also really good.  I can now have the Ethos 21 in my ED80 widefield scope at x23 and 4.4 degrees, whilst also having the ES100 20mm in the ED127 yielding x45 and 2.2 degrees of field - nice for big clusters. 

So all in all I find that 6 Ethos are ideal, plus an N T6 3.5mm at the top end and an ES82 degree 30mm at the wide field end to round out the range.  8 eyepieces (6 Ethos) covers the entire range for me in all 4 of my scopes (ok it's actually 9 EPs in total as I have the ES 100 degree 20mm so I can run 3 scopes at a time). 

 

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Hello. I think part of the hobby is collecting and it is normal to collect in your chosen hobby. But i think the other part is we are all individuals. What eyepiece works for you one night on a target may not work for you another night on the same target .People's moods vary ,sometimes you like  to see  a planet in a narrow  field of view such as a Ortho , as you can concentrate purely on the planet   , if you had a 100 fov you may still get a good view of the planet but more than likely you will get distracted more by the many other objects now in the large field of vew . It also comes down to variety and experimenting  with different eyepieces ,you may feel a certain eyepiece works better in one scope but not so well in another . Therefore you may feel you need to taylor your eyepieces for numerous scopes, for clarity, or a field of view works better in a particular scope compared to another.

I see swamp thing believes he could just have just two eyepieces(100degree) and a powermate. He may be able to get away with this combination, but would he not feel he is not getting the best benefit from his scope with such a limited number of eyepieces, and would he not feel he is also not getting the best views of a particular targets also with such a limited number of eyepieces. I would feel this. I think it's a bit like somebody who goes fishing even though a certain bait may work for him most of the times, there are times, conditions,fish temperament that mean he needs other baits to catch them. I think if you limit your eyepiece to just two and a powermate then you are limiting your image combination and therefore your views and enjoyment of the hobby. Just my opinion☺     

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I think one of the best advantages of the 100 degree EP is the great FOV when you have a scope which is not driven. For some time I had two scopes a 10" Dob plus my 4" APO frac and I only used the 8mm, 13mm and 21mm Ethos EPs. For some unknown reason I decided to have a total rethink on the Scopes and EPs that I was using. I sold the 10" Dob and my collection of Ethos EPs and bought an Orion VX8 and a collection of ES 82 degree EPs from 4.7mm to 24mm (7 EPs) - I was happy with this arrangement or so I thought.

I have now bought a 12" Dob and still have the ES collection but I have added the 20mm Myriad and I can now see why I had my original collection of Ethos EPs.

So to answer the question knowing my current collection of 12" Dob, Orion VX8, Orion VX6L, 4" APO frac what 100 degree EPs is ideal. Sticking to Ethos EPs I would say 6mm, 8mm, 13mm and 21mm plus a 2X Powermate.

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37 minutes ago, Timebandit said:

Hello. I think part of the hobby is collecting and it is normal to collect in your chosen hobby. But i think the other part is we are all individuals. What eyepiece works for you one night on a target may not work for you another night on the same target .People's moods vary ,sometimes you like  to see  a planet in a narrow  field of view such as a Ortho , as you can concentrate purely on the planet   , if you had a 100 fov you may still get a good view of the planet but more than likely you will get distracted more by the many other objects now in the large field of vew . It also comes down to variety and experimenting  with different eyepieces ,you may feel a certain eyepiece works better in one scope but not so well in another . Therefore you may feel you need to taylor your eyepieces for numerous scopes, for clarity, or a field of view works better in a particular scope compared to another.

I see swamp thing believes he could just have just two eyepieces(100degree) and a powermate. He may be able to get away with this combination, but would he not feel he is not getting the best benefit from his scope with such a limited number of eyepieces, and would he not feel he is also not getting the best views of a particular targets also with such a limited number of eyepieces. I would feel this. I think it's a bit like somebody who goes fishing even though a certain bait may work for him most of the times, there are times, conditions,fish temperament that mean he needs other baits to catch them. I think if you limit your eyepiece to just two and a powermate then you are limiting your image combination and therefore your views and enjoyment of the hobby. Just my opinion☺     

I'm not entirely convinced only having x3 82° ep's and an extender would be limiting yourself in any way though ???

I started a thread some time ago where it came up in conversation several times that above all exit pupil played the largest part in offering the best views available to the MKI eyeball. Off the top of my head I think it was 2-3mm for DSO's and 1mm for planets. Apparently this is an optimal exit pupil for the human eye. Given we don't have the abilities CCD's or DSLR have to vary exposure it all made sense when thinking about it. Kind a like the optimum exposure for the eye so to speak.

I know most beginners will drop in the shortest focal length eyepiece to try and achieve x500 magnification expecting a dinner plate sized image only to see an undesirable dull mush. Later complaining their scope doesn't work or the views were not as pictured on the box. I'm sure we have all been guilty of it but as we settle in to the hobby we learn that there is more to it than just magnification. In the case of Steve I am sure he has 3 ep's that will on all but the worst of nights cover most of his needs and powermates are no slouch at bumping up the mag to double the amount of focal lengths at his disposal. You also need to take in to account that x3 82° ep's do the job of several plossl. I might also add that Messier compiled his catalogue with probably little more than a 50° FOVl. I'm also taking a gamble on him having a limited amount of focal lengths at his disposal.

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With the Ethos range, I've seen it said that there are 2 sub-sets of 3 which seem to deliver very useful coverage, depending on the focal length of the scope. The 21-13-8mm are one sub-set and the 17-10-6mm the other.

I agree with Mark on the advantage that a hyper-wide field can provide when manually tracking a scope. Another is where you are seeking to keep to a reasonable exit pupil while having a wide expanse of sky on view.

They are not everyones "cup of tea" though, thats for sure.

 

 

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When I see through an Ethos eyepiece I say "wow" but I don't intend to buy one of these. The reason is how big and heavy they are. My collection consists of  T6 and T5 naglers, all of them are small and lightweight. The size and weight is very important thing for me personally. 

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Tele Vue did an amazing job shrinking the Naglers from their large and heavy T1 and T2 sizes to the compact and relatively lightweight T5 and T6 1.25" formats while managing to improve the optical performance as well :icon_salut:

 

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Interesting. A full set of Ethos does indeed weigh somewhere between daft and barmy and takes a big case to move around at once. The main reason for having them all is not wanting to think about what I might be missing by not having a particular one... And now I'm content to get on with it and perhaps find out which - if any - I could do without. Then again, with a full set I do feel prepared for any scope that may come my way in the future...As my observing style and preferences evolve, I'm sure I'll figure it out.

They are all just so nice...

:happy11:

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19 minutes ago, DRT said:

 

Hi, I'm Derek, and I'm a Collectionist :rolleyes2:

 

And not just Ethos :D:D:D:D 

I will give you your dues I have seen your name attached to a few in the for sale section of late. My guess though that's more down to Mrs T wanting some room back. :D

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3 minutes ago, spaceboy said:

And not just Ethos :D:D:D:D 

I will give you your dues I have seen your name attached to a few in the for sale section of late. My guess though that's more down to Mrs T wanting some room back. :D

Nah... He wants to buy a Tak.

:evil4:

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23 minutes ago, spaceboy said:

And not just Ethos :D:D:D:D 

I will give you your dues I have seen your name attached to a few in the for sale section of late. My guess though that's more down to Mrs T wanting some room back. :D

 

20 minutes ago, iPeace said:

Nah... He wants to buy a Tak.

:evil4:

Actually, it's a 11 or 14 inch SCT I'm planning :wink:

...and Mrs T is a star, she just lets me get on with it :smile:

 

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1 hour ago, spaceboy said:

I'm not entirely convinced only having x3 82° ep's and an extender would be limiting yourself in any way though ???

I started a thread some time ago where it came up in conversation several times that above all exit pupil played the largest part in offering the best views available to the MKI eyeball. Off the top of my head I think it was 2-3mm for DSO's and 1mm for planets. Apparently this is an optimal exit pupil for the human eye. Given we don't have the abilities CCD's or DSLR have to vary exposure it all made sense when thinking about it. Kind a like the optimum exposure for the eye so to speak.

I know most beginners will drop in the shortest focal length eyepiece to try and achieve x500 magnification expecting a dinner plate sized image only to see an undesirable dull mush. Later complaining their scope doesn't work or the views were not as pictured on the box. I'm sure we have all been guilty of it but as we settle in to the hobby we learn that there is more to it than just magnification. In the case of Steve I am sure he has 3 ep's that will on all but the worst of nights cover most of his needs and powermates are no slouch at bumping up the mag to double the amount of focal lengths at his disposal. You also need to take in to account that x3 82° ep's do the job of several plossl. I might also add that Messier compiled his catalogue with probably little more than a 50° FOVl. I'm also taking a gamble on him having a limited amount of focal lengths at his disposal.

 

Hello. I raised the point of swamp thing introduced and in my opinion 2 eyepieces of 100 degree and a powermate would be very limiting. If my maths are right then a total of 4 different magnification. With the atmosphere conditions in this country and the seeing conditions ,at  times you need to go up in 1mm intervals ie,4, 5 ,6,7 mm to possible get the highest magnification for the seeing conditions that night for planetary work at that time for the best detail that night. If the conditions are really poor then you may have to start at even 7 and work up off that starting point. How is just 4 magnfication going to work for planetary use? You need very small jumps at times. Why did Mr Nagler come up with the zoom 3/6  with all the combinations (if you could get away with just 2 eyepiece's and a powermate  ?  

To me and IMO then a range of 4 magnifications is a very limiting range especially if you wish to do planetary and DSO. I don't think I could realistically be so limited. And for those disagree with me and who do feel they can agree with 2 eyepieces and a powermate, then I am looking for some nice eyepieces so please contact me as I must be a Collectionist ? 

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as someone who observes with steve, I too only use two ethos on most galaxy hunting sessions...its 21E to locate then 8E for a close up...this is what we do and for fuzzy hunting theres no need to go 21,17,13,10,8,6.....blah,blah Planets maybe but we don't do planets that's why he can get away with perhaps only two EP's.

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Hello estwing , that explains a lot. That's what I have been trying to say all along. That obviously you are very limited with a couple of eyepieces. And if all you do is fuzzy hunting then I can understand this. But for me and I am sure a lot of members out there we like to go for planetary as well as DSO and just a couple of eyepieces did just not make logical sense to me to cover everything. And I felt it was not showing the full picture.  Now that it has been explained that you more or less go for DSO this becomes a lot clearer. I have probably upset the Dob mob by the looks of things and that was not my intention. As you guys have a lot more overall knowledge and experience than me. My intention was try to give a rounded view to why a felt limiting the amount of eyepieces (magnifications available) limited what and how you can observe. Thanks Chaps☺

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....I don't think you've upset anyone!?:thumbright:...for different targets you need different tools!...planets and lunar may need a close jump between ep's but DSO hunters get away with a couple of cheap ep's and a big mirror!!!!?!!!:rolleyes2:

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I get what you are saying Timebandit and this was raised in my opening post that often 8mm and below requires several focal lengths to combat seeing. Obviously scope dependant as SCT's are a whole other ball game.

I also get that someone who has a large light bucket often has so to pick out faint and fuzzies so bright planets and high magnification may not necessarily be on their agenda. That said 2 - 3 eyepieces plus extender seems more than adequate.

I suppose again in the same way those who have middle ground telescopes of 10" and up in aperture want to dip their toes in both puddles wanting both deep sky and planetary views. Those with smaller scopes may reside to just lunar and planets. I can see the appeal of a 100° eyepiece for high magnification planetary observing if you do not have a driven mount but I would though beg the question that if your interest also lie in planets why you would not consider a driven mount. Surely what could be spent on 3.7,4.7,6 & 8mm ethos would more than cover the cost of a driven AZ or EQ mount and plenty of change left over for a set of planetary ep's. I know it can be a fuss to set up driven mounts and they aren't everyone's game of cricket but a planet or even double star isn't going anywhere even in a 40° eyepiece. As others have mentioned it is not always a benefit to have such a lot going on in the back ground when observing planets even when it means at 100° you can keep it in the FOV for longer with out nudging.

I think there has been some valid points made for those who feel the need to have a complete set of 100° eyepieces. Most notably that most astronomers do have more than one telescope so focal lengths / magnifications do vary. I do also agree that we do like to collect things. I do though feel this is due to the culmination of media and commercial manipulation over the years more so than true personal preference. It is salesmen doing their job and doing it well. The best of those are the ones who make you sell the stuff to yourself. Make it uniformed or desirable and even if there are runts in the litter you'll still want them.

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I have many scopes. I have many eyepieces. There is little or nothing they can't do given the right sky conditions. That mostly takes my incompetence out of the equation. 

 

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12 minutes ago, spaceboy said:

.... I do though feel this is due to the culmination of media and commercial manipulation over the years more so than true personal preference. It is salesmen doing their job and doing it well. The best of those are the ones who make you sell the stuff to yourself. Make it uniformed or desirable and even if there are runts in the litter you'll still want them.

Makes some of us sound rather gullible :icon_scratch:

 

 

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