Comparing Explore Scientific 2 inch 100 degree apparent FOV eyepieces with Ethos eyepieces

[athornett]

Please tell me what you think about the new Explore Scientific 100 degree FOV eyepieces and, if you have the experience, how you think they compare to Televue eyepieces. I will put my cards on the table - I bought the ES 20mm on the special offer currently available from USA (via OPT online) - arrived within 3 days and I love them! £300 all in in cluding postage and tax on entry to the UK, roughly half an Ethos. I was so impressed I bought the 9mm and 14mm second hand from Astro buy and sell.

My observing buddy has a collection of Ethos eyepieces and in our comparison we feel the ES and Ethos are comparable, although the ES has a warmer tone which you either like or you don't, I suppose....

They are also bigger and heavier - important if your telescope is relatively light weight.....which mine isn't!

However, don't get lead astray by me. Please tell me what you think, warts and all. There are others out there who want to know whether they should save and buy one Ethos or whether they can use the money to get 2 x ES. Important decision with a lot of money at stake.

Then again - you might feel that this Ethos and ES stuff is a waste of money - perhaps in your opinion they just aren't worth it and we should buy Naglers or Delos eyepieces or another brand instead because you think it is as good. Please also make your thoughts known.

If it turns out that every one thinks I have wasted my money then I'll just have to cope!

Andy

[Bart]

I have the same 20mm. You definitely didn't waste your money as its a great EP. At half the price I understand it definitely ain't half the EP.

Enjoy them. Don't be beating yourself up.

Only problem in this part of the world is getting a chance to use them!!!

Barry

[Stargazer_00]

If you're happy then you didn't waste your money. Beauty is in the eye of the beholder as they say and so long as you are pleased then literally nothing else matters.

If I met someone who said they felt the supplied 10mm Plossl eyepiece was better in their eyes than a 10mm Delos then I'd pat them on the back and call them lucky.

[SimonfromSussex]

This is really good to hear Andy, I was looking at the 20mm 100 degree (I had heard good things).

Can I ask how fast your scope is that you use them in and what the edge of field is like in your scope?

Cheers

Si.

[Mark in Macc]

There is an ES 100 20mm in the classifieds. Virtually brand New, the owner doesn't get on with it because he wears glasses.

[Mark in Macc]

I really like mine, but it is in a slow scope though. John, one of the forum moderators on here thinks they are good and has bought one. There are good reports from across the pond as well on Cloudy Nights. Are they as good as the Ethos? Probably not, but for the price they have a lot of admirers.

[crashtestdummy]

Love mine,great views and great price when ordered from the US.as said there's a nearly new one in the classifieds.

Don't know how it compares to an Ethos other than it's half the price

[Damo636]

I think optically there's not a lot between the ES/Televue 100º range, but ergonomically Televue just edge it. The 21 Ethos 15mm of eye relief is just about the bare minimum I am comfortable with and don't think I could get on with the ES 100º which has less due to the recessed eye lens. Each to their own though but one thing is for sure, the ES equivalent's are exceptional value!

[Moonshane]

I am pretty loyal to Televue and of my 15 eyepieces, all but three are TV and the other three are BGOs. I have one ethos, a 13mm and personally, I'd not buy another. as good as it is I feel it's possibly too big an investment in one eyepiece and I like the flexibility of a wider range, especially at the higher magnifications.

What I do know is that any eyepiece of this sort of quality (and I include the ES, TV, Pentax and some of the Baaders) will be very close in optical quality even in fast scopes, especially if a coma corrector is used.

Personally, I use a wide range of eyepiece styles and like/enjoy them all. From BGOs with 40 degree field, tight eye relief and keen sharpness, to TV plossls with sharpness and narrow 50 degree field, to Radians with great sharpness and long eye relief and 60 degree field to Naglers with 82 degree field and wonderful sharpness to my one Ethos which has a ridiculously wide field and great sharpness and contrast (but I really don't like on the moon).

Whatever you buy in this class you cannot go wrong quality wise, but if I had the choice between say a new 13mm Ethos and a pair of used 12mm and 17mm Naglers at the same price approx, I'd go for the latter any day. Not sure if this helps but hopefully you can translate the comments to whatever eyepieces you are considering.

Based on comments from others you have certainly not made a mistake.

[athornett]

Focal ratio in my scopes used with the Explore Scientific 100 degree eyepieces (I have got 9mm, 14mm, and 20mm eyepieces):-

10" Dark Star = F5.8

12" Lightbridge = F5.0

16" Lighbridge = F4.5

8.6" David Lukehurst = F7.2

All are Dobs.

Dobs suffer from a lot of coma towards edge of field and I find this dominates in the view so can't really comment on the stars at the edge - espec with 100 degrees where you are really off axis by time you get to field stop.......mind you trying to find the field stop with your eye in 100 degrees is quite difficult -you have to appear around and under the edge of the eye lenses as the field just seems to go on for ever!

Therefore I have a Paracorr which improves this situation a lot - I know Damian also uses a Paracorr with his Orion Dob and Ethos eyepieces for same reason.

Of course, the great thing about 100 degrees in a dob is (i) so much more field to use ot star hop (ii) takes longer for object to cross field of view so less nudging of the scope.

In the centre of the eye lenses, the ES (as are the TV Ethos) capable of producing an image with multiple diffraction rings in the Airy disc WHEN I have got the collimation right - talking of which best bit of kit I have found for collimation is the Catseye Infinity collimator.

Andy

[alan potts]

I have most of the Ethos eyepiece range and whether they are worth the money is a question that is totally personal, to me they are. I didn't buy all of the new, in fact only two of them. I am pleased that people are happy with the ExSc versions which are generally regarded to be copies of the Televues, though as the focal lengths are not the same I don't know how people arrived at that.

I think it is a great deal to do with ExSc that we have just seen a large price reduction in TV's which is very good for all of us in the hobby.

Myself I would not swap my Ethos's but If I started all over again I am not sure if I would have bought them instead of the ExSc 100 degree range. John is very happy with his 20mm ExSc and he knows what he is talking about and has TV's to compair with, so they must be good. I wish I had a 20mm to do a head to head with over a good few nights in my scopes to see for myself.

Alan

[John]

As Alan says, I have the 6mm, 8mm and 13mm Ethos's and have recently added the 20mm ES 100 to my eyepiece case. I'm a great admirer of Tele Vue eyepieces but I could not justify the additional £300 (as it would have been then) to get an Ethos 21mm.

My views on the ES 20 100 are nicely expressed by Damo above. Great value 100 degree eyepieces and very impressive to use. Another reviewer on another website likened them to a 100 degree Nagler and thats a pretty good assessment too I reckon. The Ethos eyepieces do make a small performance step up over the Naglers I've found and not just in the additional field of view and eye relief.

If I had very fast scopes (ie: around F/4.5) I might have saved the extra for the Ethos but my fastest is now F/5.3.

I guess if I'm really honest I feel the ES 20 / 100 is a very small compromise over an Ethos and I would have gone for the latter had price not been an issue at all. £300 is a lot to overlook though

Hopefully I'll be able to compare the ES 20 / 100 to an Ethos 21 at the next SGL star party. That will be an interesting experience

[Stargazer_00]

Looking forward to SGL for sure. Hope I get a ticket this year!

[athornett]

I know I am being naughty here and broadening my own topic outside of its original remit, but Damian has a 31mm Nagler - I feel there is something about that beast which just defines the space walk experience and none of these other eyepieces we are discussing seem to come close. Would you agree? My excuse for adding this question for discussion is that part of the pro-100 degree argument (and hence part of comparing ES with Ethos) is the idea that they provide this spacewalk feeling........

Andy

[John]

I also have a 31mm Nagler and it's superb eyepiece. The ES 20 / 100 is a bit more immersive for me though, especially with the rubber eyecup rolled down. It creates the "endless pool of stars" effect a little more than even the "Terminagler" does and produces a darker background sky as well. The Nagler does show more sky though and is my "go to" eyepiece for really large objects such as the Veil nebula.

[crashtestdummy]

I fond th view through my 30mm es 82 is brighter than my 20mm es 100.they compliment each other well

[athornett]

We have compared the Explore Scientific 20mm 100 deg with the Ethos 21mm - similar performance but warmer tone on the ES. ES lot heavier - relevant if your scope can't take an elephant hanging out of the focuser - thankfully mine can so not a problem!

Andy

[gasellers]

I realize I'm resurrecting an extremely old thread, but since I started reading about the differences between the Ethos and the Explore Scientific 100 deg EPs, I'm feeling a lot of stress trying to decide which to buy. I really like the fact that the ES EPs are waterproof where I don't see the same claim with Ethos. I worry about getting moisture and possibly fungus if I choose to go with the Ethos. I'm new to all of this, so if my worries are unfounded, please tell me. The other thing that has me leaning towards the ES EPs is the cost difference of course. Especially when from the reviews I've seen, there is very little difference in performance. I'd appreciate any thoughts you all might have on this.

[John]

I've owned both Ethos and ES 100's and I've used other 100 degree eyepieces as well.

There is very little difference in performance between an ES 100 and an Ethos unless you plan to use it in a big aperture fast dobsonian and even then I suspect the differences would be minimal.

Despite this I did move from the ES 20mm / 100 to the Ethos 21mm 100 - I am a great fan of Tele Vue's products

I've owned Ethos eyepieces for a few years now and our observing conditions in the UK can be pretty damp at times. I've never experienced any issues with damp getting inside an Ethos. They have been covered in dew a few times but have suffered no ill effects at all as far as I can see

I have Pentax XW eyepieces which also have a degree of waterproofing but the other eyepieces that I have without the feature don't seem to be at any disadvantage.

Personally I don't see the Ar / Ni purging and waterproofing as a big sales point for the ES 100 eyepieces but their fine optical performance at a price point well short of the Ethos certainly does make them very worthy of consideration

[estwing]

To be honest they're good but in fast scopes the difference starts to be more evident they just don't snap into focus like the ethos

[gasellers]

Awesome. Thanks for the comments. I have an F/5.9 dob. Is that considered a 'fast' scope?

[estwing]

Not really you should be fine

[Scooot]

I tried an ES 100° and the eye relief was a big problem, I had to return it. I've only tried the 13mm Ethos but that is far better so if eye relief is important the Ethos will be better.

[John]

Awesome. Thanks for the comments. I have an F/5.9 dob. Is that considered a 'fast' scope?

I was using the ES 20mm / 100 in my 12" F/5.3 dobsonian and it worked pretty well with that. I could just see a little coma out towards the edges of the field stop but the scope produces that, rather than the eyepiece.

[-Aldebaran-]

I would love to do a comparison of the 100° ethos and ES! If anyone wishes to borrow me their's?

I shall take my time and you can have them back in say, a year or two!!!!!