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Wide TFOV 1-1/4" Eyepiece

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#26 Rustler46

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Posted 25 November 2019 - 08:22 PM

Given the AFOV preferences you like, the 24 Pan or 24 ES68 would probably be the way to go.  Also, considering you have f/5 instruments in the mix, not letting the eyepiece focal length get too long so the exit pupil stays less than 6mm so sky backgrounds stay darker will be a plus for the 24mms.  I've had both of these, sold the Pan and kept the ES as they were close enough in performance that I could make productive use from the saved funds - ES is generally $159 vs. $289 for Pan.  https://www.cloudyni...omparison-r2651

Bill, thanks so much for that most informative review of 24-26mm eyepieces. I can only imagine the amount of effort that was required. Also your great observational skills were quite evident and appreciated. While this review from some years ago didn't include all three eyepieces on my short list, it did give a nice comparison on two of them (ES 68° and the TV Panoptic). I also appreciated how one of my favorites faired well in some respects - the Celestron Silvertop. I now own two of these for use in my WO binoviewer.

 

I appreciate your take on the ES 68° being your choice over the TV Panoptic. My own paradigm in visual astronomy is to just make the best of whatever conditions are extant. These include telescope performance as affected by such things as aperture, design (SCT, Newt, APO, etc.), light pollution and atmospheric clarity. So in that regard I don't usually obsess over what could be "best" - in my view "It is what it is" and "What can I see under these conditions?".

 

With these thoughts in mind, I'm becoming much more inclined to get the TV Panoptic. While it is not "best" in all categories, is good in most and excels in some categories. Based on my preference for the 11mm Nagler T6 of all my various eyepieces, the Panoptic would very likely be among the most used eyepieces. It is the most expensive of those on my short list. But you get what you pay for (at most). 

 

Your comprehensive review has really brought out that eyepiece design is an exercise in compromise - in balancing a number of competing performance outcomes. Manufacturing costs, materials available, retail price and a wealth of optical parameters are juggled by the designer. So the end user also assesses a number of these outcomes in choosing which eyepiece meets his needs. Once again your review was most enlightening. Perhaps you may be moved to do another review on the currently available offerings.

 

The only doubt still in my mind is how the APM UFF 24 compares against the other two. Its very reasonable price is a real plus, especially considering it is an 8-lens design. I'm not aware of many reviews of the APM, particularly compared to the ES and TV offerings. But as I recall Don Pensak reports the Panoptic is the clear winner of the 3 in aberration-free presentation over the entirety of the FOV. And multiple reports over the years have given the Panoptic excellent marks.

 

So unless I hear otherwise in the short term, I'm ordering the Televue Panoptic while it is still on sale. I know the question posed by my original post has been discussed many times over the years. So I appreciate everyone's patience with me if giving their views on the subject. If my Explore Scientific 20mm 100° eyepiece does sell, it will more than pay for the Panoptic. I'm not much inclined to drop the price a lot for a pristine condition eyepiece. If it doesn't sell, it may well ride on my piggy-backed AT115EDT triplet APO. With a 2-1/2° FOV it gives an outstanding view, particularly at the low 40X magnification produced by an 805mm focal length.

 

Thanks again for all who contributed to my decision!

 

All the Best,

Russ



#27 Rustler46

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Posted 25 November 2019 - 08:38 PM

Russ, I've used all 3 in an f/5 scope, coma-corrected to f/5.75.

The 24mm Panoptic is the sharpest of the 3, with no caveats on my part.

The APM had good contrast, and was very sharp in the center 50%, but displayed astigmatism in the outer field, as did the ES.

All 3 of them behaved similarly in my 4" triplet apo, but outer field astigmatism was reduced.

Don, thanks so much for taking the time to respond. Your expertise in all matters-eyepiece is much appreciated. Your take on the 3 in my short list has helped me decide on the Panoptic. I will need patience since the eyepiece will likely be in my possession before I get another clear night. Both Oregon and California are in store for a historic wind/rain/snow event.

 

Best Regards,

Russ



#28 Rustler46

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Posted 25 November 2019 - 09:16 PM

I have been wanting to get away from most of my 2-inch eyepieces. This is because of the off balanced weight on diagonals when pointed to the side for viewing comfort in my SCTs and refractor. My telescopes are:

  1. 10-inch Dob, f/5 to f/5.5 (w/ coma corrector)
  2. Celestron-8, f/10 to f/6.3
  3. Celestron-11, f/10 to f/6.3
  4. AT115EDT APO triplet, f/7

Telescopes 3 and 4 are the most used with the APO riding atop the C-11. Eyepieces under consideration are:

I don't demand the premium performance that the Nagler design would provide at the premium price. Besides I prefer something less than the 82° AFOV. Something around 65° AFOV is just fine for my uses. I am drawn to the Panoptic, based on Televue's established reputation of quality performance. The other two eyepieces have their adherents. I'm looking for widest true FOV with decent edge of field performance with the telescopes I most use.

 

So I would welcome comments and suggestions.

Thanks to all who offered their advice! I've decided to get the Televue 24mm Panoptic. So I'm looking forward to an opportunity to test that wide-field 1-1/4 inch eyepiece. It will not likely disappoint.

 

I also wanted to share something I realized when considering my eyepiece choice. The problem I have been having with heavy 2-inch eyepieces involved more than just weight. It also is affected by the length of the eyepiece. That parameter along with weight distribution along the length contributes to the amount of torque applied to the diagonal when in other than near vertical position. 

 

So while the 2.1 pound  (1.0 kg.) weight of my ES 20mm 100° is a factor, its length of over 4-1/2 inches (11 cm) above the eyepiece holder is also a big factor in the off balanced weight it produces. So this is something you-all might consider.

 

Best Regards,

Russ


Edited by Rustler46, 26 November 2019 - 02:47 AM.

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#29 gezak22

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Posted 25 November 2019 - 11:19 PM

The 24mm Panoptic has zero barrel distortion (negative rectilinear distortion).

It does, however, have a lot of pincushion distortion (positive rectilinear distortion).

Total distortion is around + 5.5%.  This is because of vanishingly low angular magnification distortion.

...

Thank you for the clarification. One of these days I will get the definitions right.



#30 Peter Besenbruch

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Posted 26 November 2019 - 01:46 PM

Some random comments. Your choice is between a shorter wide angle (24mm) and a longer Plössl. At f10, both would be fine in suburban settings. At f5, something shorter would be a better choice.

 

My experience: ES62° 26 is a nice comfortable eyepiece. It won't do so well at f5, but at f10 it should  be fine. I own 2, the 20 and the 14. I have noticed that ES doesn't do a good job blackening the interior, and there is a bit of a hit to contrast compared to other eyepieces, like the BST Flat Field 27mm. Also, the series has a tendency to ghost.

 

The ES68° 24mm, and the Panoptic 24mm both have good reputations. I have used the Panoptic 27mm. Things to keep in mind: Edge correction will be first rate, pincushion distortion will be fierce, and there is significant lateral color.

 

Other eyepieces to consider come from APM (the UFF series, no experience), the Meade HD60 25mm (have had quick views). It's a good eyepiece, but at f5 the edge will suffer a bit. There is the 25mm Barsta ED 25. Again, good at f10, some edge astigmatism and field curvature at f7.5, and I can imagine it will get pretty soft at the edges at f5. The Baader Hyperion 24mm: Perhaps the most vivid color rendering of the series. Also the widest true field of all the eyepieces mentioned. Edge performance was OK at f7.5, good at f10, and at f5 you might want to run screaming (OK, how about walk away quickly).

 

Your choice of the Panoptic 24 should do you fine.


Edited by Peter Besenbruch, 26 November 2019 - 01:48 PM.

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#31 Jon Isaacs

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Posted 26 November 2019 - 02:04 PM

Don, thanks so much for taking the time to respond. Your expertise in all matters-eyepiece is much appreciated. Your take on the 3 in my short list has helped me decide on the Panoptic. I will need patience since the eyepiece will likely be in my possession before I get another clear night. Both Oregon and California are in store for a historic wind/rain/snow event.

 

Best Regards,

Russ

 

Russ:

 

My two belated two bits:

 

Bill choose the ES 24 mm over the 24 mm Panoptic because he felt the improve in edge correction of the Panoptic did not warrant the extra cost.

 

I have the 24 mm Meade Series 5000 SWA, the optical twin of the ES 24 mm 68 degree and the 22 mm Panoptic. My scopes are fast and I'm picky about edge correction, I use a Paracorr at F/5.5 with Naglers, Panoptics and Ethos..

 

The 22 mm Panoptic is better corrected than the Meade but I really have to look to see it.

 

I tend towards Bill's recommendation. I think the Naglers and Ethos's are noticeably/significantly better than the competition but at least the 24 mm ES is close enough to the Panoptic to justify it's purchase.

 

Jon


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#32 25585

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Posted 26 November 2019 - 02:06 PM

Meade HD-60 25mm has a good reputation.



#33 Starman1

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Posted 26 November 2019 - 02:14 PM

Meade HD-60 25mm has a good reputation.

Alas, it is discontinued, though many likely remain in dealer stocks.

And the field stop is not the widest possible in a 1.25"barrel.

The optics though, seem to be the same as the Celestron X-Cel LX 25, so might be more universally available.



#34 SeattleScott

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Posted 26 November 2019 - 03:59 PM

I went with the Meade HD-60 because I didn’t want to spend a lot on a wide field 1.25” when I will normally be using my 2” for wide field. And with an F4 scope I wanted excellent edge correction, although it mostly gets used at higher F ratios. But yes it only has a 25mm field stop not 27, only 60 AFOV not 68, and he is selling a hyperwide so he should be able to pay for the Panoptic. Given this would be a primary low power eyepiece for him it makes sense to get the best. The Meade is great for people who can’t afford $300 eyepieces or won’t be using it as a primary eyepiece.

Scott
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#35 Rustler46

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Posted 26 November 2019 - 04:36 PM

I went with the Meade HD-60 because I didn’t want to spend a lot on a wide field 1.25” when I will normally be using my 2” for wide field. And with an F4 scope I wanted excellent edge correction, although it mostly gets used at higher F ratios. But yes it only has a 25mm field stop not 27, only 60 AFOV not 68, and he is selling a hyperwide so he should be able to pay for the Panoptic. Given this would be a primary low power eyepiece for him it makes sense to get the best. The Meade is great for people who can’t afford $300 eyepieces or won’t be using it as a primary eyepiece.

Thanks for your comments, Scott. As long as my expensive purchases aren't too frequent, my dear wife (who is still working full-time) is supportive of my astronomy pursuits. At least nowadays it keeps me mostly at home. The two of us did make an effort traveling to my dark site to see the meteor storm that didn't happen. Few meteors were seen, but the sky was spectacular, with the Zodiacal band evident.

 

From some comments in this and other threads I have come to realize that for an f/5 Newtonian, like my Hardin (GSO) 10-inch, one needs to prevent eyepiece induced astigmatism first. A premium eyepiece like the Panoptic does well in this regard. Then my (relatively inexpensive) GSO coma-corrector can finish the job of cleaning up the image. 

 

While astronomy equipment can be expensive, it's not like having a horse with ongoing upkeep or maintenance costs.  Usually I go for the economy route if the difference isn't too great. My eyepiece collection attests to earlier times when finances were more constrained. But when I have gone for the best (or better) option it has not disappointed.

 

Best Regards,

Russ


Edited by Rustler46, 26 November 2019 - 04:42 PM.


#36 SeattleScott

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Posted 26 November 2019 - 05:39 PM

The Meade HD-60 25 (or Xcel LX 25) are great for fast scopes also. In lab testing at F4 the Meade was essentially identical to the 24 Panoptic in terms of field correction. But the Panoptic has more AFOV and a touch wider FOV, possibly a little better polish, baffling, QA, etc. Not knocking the Panoptic; it tested extremely well. Better than ES/Meade. It just happens the Meade tested extremely well too. The Meade HD-60 have sometimes been compared to Radians as they have the same AFOV, enough ER for glasses, and some of them are very well corrected like the Radians. The real difference is all of the Radians and Panoptics tested well, but not all the HD-60/Xcel tested well. But at 25mm focal length you do get similar performance for a lot less money. Still, pretty much everyone agrees the Panoptic 24 is still a little bit better, more AFOV and TFOV if nothing else.

I have the Meade 25 HD and a 15 Panoptic. Not close enough to really compare them, but they are both sharp, contrasty eyepieces that perform well down to F4. Certainly you can’t go wrong with a 24 Panoptic or 25 HD/Xcel, but if you can swing it, the Panoptic makes sense since it will be one of your most used eyepieces, and since you can afford the Panoptic by selling your ES.

Scott

Edited by SeattleScott, 26 November 2019 - 05:42 PM.

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#37 MartinPond

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Posted 27 November 2019 - 08:29 AM

In a world of asymptotic price vs. afov, you can get some excellent EPs with 60deg afov!

The Paradigm Dual ED is less, but has a 15mm eye relief compared to the HD-60 at 17mm..

...or is that a simple matter of different sameness?   Not sure.. 



#38 SeattleScott

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Posted 27 November 2019 - 02:12 PM

The problem is 15mm usually isn’t quite enough for eyeglass wearers, and the 17-18 that the Meade/Celestrons have is usually just enough. So if you don’t wear glasses, then the difference is little, and you don’t really care. But if you do observe with glasses, that extra 2-3mm makes a real difference.

Scott

Edited by SeattleScott, 27 November 2019 - 02:13 PM.


#39 25585

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Posted 27 November 2019 - 04:15 PM

Millimetres are small units but its amazing how much difference a single figure amount can make.

 

I have found out, at considerable expense sometimes, that quoted & use-reported figures, should be taken with a fistful of salt. Effective eye relief is what counts, that distance from the edge of a barrel rim upwards. But equally important is exit pupil comfort and lack of black-outs of part of the FoV from any cause. 

 

 Microscopes are static instruments looked into, downwards, by static observers who move the objects being observed around, and more amenable enviroment and ergonomics generally. More restrictive optical designs can be acceptable for microscopes. But the exact opposite is true for telescopes, where instrument and observer are perpetually in motion following a moving object. Its easier & less stressful to study and count microscopic objects (unless rapidly multiplying or moving), than a fieldful of galaxies looking into a telescope eyepiece. Tracking an individual moon around Saturn or Jupiter can be intense, though satisfying.

 

I feel that for astronomical eyepieces, their scientific optical design excellence for asking prices is generally fair, but the ease of viewing comfort for the telescope user leaves room for improvement. Perhaps the microscope designs have too much influence on telescope eyepiece design, the designers may also be working, or have in the past, in different optical areas. 


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#40 Starman1

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Posted 27 November 2019 - 05:00 PM

Millimetres are small units but its amazing how much difference a single figure amount can make.

 

I have found out, at considerable expense sometimes, that quoted & use-reported figures, should be taken with a fistful of salt. Effective eye relief is what counts, that distance from the edge of a barrel rim upwards. But equally important is exit pupil comfort and lack of black-outs of part of the FoV from any cause. 

 

 Microscopes are static instruments looked into, downwards, by static observers who move the objects being observed around, and more amenable enviroment and ergonomics generally. More restrictive optical designs can be acceptable for microscopes. But the exact opposite is true for telescopes, where instrument and observer are perpetually in motion following a moving object. Its easier & less stressful to study and count microscopic objects (unless rapidly multiplying or moving), than a fieldful of galaxies looking into a telescope eyepiece. Tracking an individual moon around Saturn or Jupiter can be intense, though satisfying.

 

I feel that for astronomical eyepieces, their scientific optical design excellence for asking prices is generally fair, but the ease of viewing comfort for the telescope user leaves room for improvement. Perhaps the microscope designs have too much influence on telescope eyepiece design, the designers may also be working, or have in the past, in different optical areas. 

Not all observers wear glasses, so not all observers need long eye reliefs, or even find long eye reliefs comfortable.

I know that's a tough concept to grasp when you yourself need and prefer the longer eye relief.

And, of course, long eye relief for a 40° field is a very different experience than long eye relief for an 80° field.  Microscopy doesn't demand the wider fields,

though I've noticed than eyepieces in microscopy do seem to be getting larger and wider.

 

Using your concept of effective eye relief, an eyepiece could have an eye relief of 25mm, but an effective eye relief for glasses wearers (call it Glasses Eye Relief) of only 15mm if it has a recessed eye lens.

The observer who doesn't wear glasses might find the eye relief excessive, where the glasses wearer might find it too short.

 

How do we deal with that?  Manufacturers are going to be reluctant to specify both eye relief figures (Design and Glasses) in their literature.

And, glasses wearers themselves need varying amounts of eye relief to be comfortable using an eyepiece.

There doesn't seem to be an easy solution here unless someone sets up an instrument to measure the eye relief of eyepieces from the top surface of the eyepiece.

And, with so many hundreds of eyepieces out there, the process of compiling such information is going to be difficult.

 

It seems the best answer we have right now is first person experience as stated here on CN or in other forums.


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#41 25585

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Posted 27 November 2019 - 05:28 PM

Too-long eye relief can be compensated for with eyecup extenders, while there is no way of lengthening a short eye relief.

 

Take the Pentax XW, Baader Morpheus, Orion LHD, TV Delos & Delite designs for example. Designed for day use by people wearing sunglasses as well as prescription. They are what I call "considerate" designs. Same for LER binoculars. Those like scaled are usually older. But "inconsiderate" are newer ranges &/or models where eye relief is kept short, but need not be.    

 

For SCT users who need 20mm effective eye relief, a max FoV Delite in 1.25" would be great. 


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#42 Rustler46

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Posted 27 November 2019 - 07:03 PM

Not all observers wear glasses, so not all observers need long eye reliefs, or even find long eye reliefs comfortable.

I know that's a tough concept to grasp when you yourself need and prefer the longer eye relief.

And, of course, long eye relief for a 40° field is a very different experience than long eye relief for an 80° field.  Microscopy doesn't demand the wider fields,

though I've noticed than eyepieces in microscopy do seem to be getting larger and wider.

 

Using your concept of effective eye relief, an eyepiece could have an eye relief of 25mm, but an effective eye relief for glasses wearers (call it Glasses Eye Relief) of only 15mm if it has a recessed eye lens.

The observer who doesn't wear glasses might find the eye relief excessive, where the glasses wearer might find it too short.

 

How do we deal with that?  Manufacturers are going to be reluctant to specify both eye relief figures (Design and Glasses) in their literature.

And, glasses wearers themselves need varying amounts of eye relief to be comfortable using an eyepiece.

There doesn't seem to be an easy solution here unless someone sets up an instrument to measure the eye relief of eyepieces from the top surface of the eyepiece.

And, with so many hundreds of eyepieces out there, the process of compiling such information is going to be difficult.

 

It seems the best answer we have right now is first person experience as stated here on CN or in other forums.

Good points, Don. I might add another variable, when glasses eye-relief is marginal. That is how tightly the observer is willing to press his glasses against the eye socket and nose pads. That will surely affect comfort for any extended viewing period. And a tight press may not be in the best interest of preventing damage to the glasses.


Edited by Rustler46, 27 November 2019 - 07:14 PM.


#43 25585

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Posted 27 November 2019 - 07:14 PM

Good points, Don. I might add another variable, when glasses eye-relief is marginal. That is how tightly the observer is willing to press his glasses against the eye socket and nose pads. That will surely affect comfort for any extended viewing period. And a tight press may not the best interest of preventing damage to the glasses.

Not tightly at all, if at all! Pressing on glasses can smear or scratch the lenses, misalign them with an eye, and bend the frame.



#44 bbqediguana

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Posted 27 November 2019 - 09:16 PM

Millimetres are small units but its amazing how much difference a single figure amount can make.

 

I have found out, at considerable expense sometimes, that quoted & use-reported figures, should be taken with a fistful of salt. Effective eye relief is what counts, that distance from the edge of a barrel rim upwards. But equally important is exit pupil comfort and lack of black-outs of part of the FoV from any cause. 

 

 Microscopes are static instruments looked into, downwards, by static observers who move the objects being observed around, and more amenable enviroment and ergonomics generally. More restrictive optical designs can be acceptable for microscopes. But the exact opposite is true for telescopes, where instrument and observer are perpetually in motion following a moving object. Its easier & less stressful to study and count microscopic objects (unless rapidly multiplying or moving), than a fieldful of galaxies looking into a telescope eyepiece. Tracking an individual moon around Saturn or Jupiter can be intense, though satisfying.

 

I feel that for astronomical eyepieces, their scientific optical design excellence for asking prices is generally fair, but the ease of viewing comfort for the telescope user leaves room for improvement. Perhaps the microscope designs have too much influence on telescope eyepiece design, the designers may also be working, or have in the past, in different optical areas. 

That is a really interesting comparison of telescope vs microscope experience at the eyepiece. I have an "okay" microscope (glass eyepiece, glass objectives, movable stage for focusing, LED lighting, metal construction, etc) and I very much enjoy using it - although its eye relief would be considered tight by telescope standards. Similarly, I enjoy using Plössls and Orthos with my telescopes and they have tight eye relief in the shorter focal lengths. Ever since I purchased an adjustable height drum throne as my observing chair with my telescope, I get the same "feel" as when I'm at the microscope. I am comfortable and I can relax nicely while observing. I actually don't like excessive eye relief where I can't be physically in contact with the eyepiece while observing. However, I do not wear glasses - so all of this may change over the next 20 years as my eyes age (I am currently 50).

 

Very interesting... great point!

Thanks!

 

Rick


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#45 F.Meiresonne

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Posted 28 November 2019 - 07:19 PM

Eyerelief is a very personal thing. Some people need loads of eyerelief others less. Some eyepieces with big eyerelief i noticed succeed in producing less blackout then others. Morpheus is one on them, so was a 13 mm Hyperion i tested a long time ago. For me it is good  the Pentax XW has adjustable eyeguards and boy i do need them. I turned them completely up.Weren't it for that i would not find them very comfortable

 

Bottom ,me too i like to touch the eyepiece to look instead of hovering over like i have to with my T6 Naglers, hovering is more difficult specially when there is alot of eyerelief.

 

I tested an eyepiece once , i believe the same design as an X-cell. I could not cope with due to the too big eyerlief,


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#46 dscarpa

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Posted 28 November 2019 - 07:33 PM

 I've got a 24 Panoptic  and 31 Hyperion Aspheric and had a 24 Hyperion. The 24 Hyperion unlike the 31 had a lot of EOFB and wasn't as sharp as the other 2. The 31 Aspheric is a good eyepiece but unlike the Pan the image distorts if your eye's not centered. I like the Pan the best there's just something  enjoyable about using it that's hard to quantify.  David


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#47 Rustler46

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Posted 28 November 2019 - 08:19 PM

Eyerelief is a very personal thing. Some people need loads of eyerelief others less. Some eyepieces with big eyerelief i noticed succeed in producing less blackout then others. Morpheus is one on them, so was a 13 mm Hyperion i tested a long time ago. For me it is good  the Pentax XW has adjustable eyeguards and boy i do need them. I turned them completely up.Weren't it for that i would not find them very comfortable

 

Bottom ,me too i like to touch the eyepiece to look instead of hovering over like i have to with my T6 Naglers, hovering is more difficult specially when there is alot of eyerelief.

 

I tested an eyepiece once , i believe the same design as an X-cell. I could not cope with due to the too big eyerlief,

Yes, eye relief and user comfort are indeed important attributes (along with wide field of view) of a good eyepiece. So your points are well taken. At next opportunity I'll take time to assess whether the old Erfle eyepiece in the original post is sensitive to eye placement. I don't remember it being subject to blackouts. Since I don't use glasses while observing its eye relief must have been at least marginally sufficient.

 

I have another eyepiece, my first one purchased 56 years ago, that I seldom use because of failing to meet the ease of use criterium. This eyepiece is a Brandon 32mm of unknown design. It is the 3rd eyepiece in the following spreadsheet:

 

Eyepiece Performance on C-11 XLT.jpg

 

While it gives decent performance over most of its 1/2 degree field, it is never used nowadays. Why? The very large eye relief and tight eye placement requirement makes it difficult to use. It must have well over an inch (25mm) of eye relief and no rubber eye guard. Thus it often suffers from blackouts and flares.

 

So you are quite right, user comfort is an important aspect of the usefulness of an eyepiece.



#48 Jon Isaacs

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Posted 29 November 2019 - 02:24 AM

So you are quite right, user comfort is an important aspect of the usefulness of an eyepiece.

 

 

As Freddy said, these are very personal things.  Some observers have difficulty with all but a few eyepieces, some can comfortably use just about any eyepiece ever made.  I seem to be in the latter group.  I prefer 10-12mm of eye relief minimum but I am able to use a 4mm Plossl without too much effort.  Blackouts and sensitive placement, long eye relief, I don't know, I just seem to naturally gravitate to the optimal position.. 

 

Jon


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#49 F.Meiresonne

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Posted 29 November 2019 - 04:05 AM

Me too i prefer something around 10-13 mm. Off course you learn to adapt to others ,T6 is a hovering thing but then again not in a rate that it is too uncomfortable. It is a part of learning to observe.

Me over the years i had some (not many) i could not cope with. I had one on my first scope, a 26 mm silvertop which had no eyeguard.

Black out all the time...the 10 mm silvertop i never had issues.

 

I have a binocular i never use also because it has too much eyerelief , about 25 mm i believe . KennyJ a binocular lover here at the forum that used to post , would certainly loved it because he Always stated to need loads of eyerelief...

 

You could start the same discussion about FOV. Personnaly i like 68°-70° the most. Because i can overview the whole FOV. Some people like a fellow observer say they can overview 82° and others ask me why doyou have  the need to overview it, you can just look around. I think they have a point. And also i  big manual driven dob a big FOV is preferable , my point here also  it is al very personal..


Edited by F.Meiresonne, 29 November 2019 - 04:15 AM.

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#50 Rustler46

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Posted 03 December 2019 - 04:27 AM

Thanks to all who offered their advice! I've decided to get the Televue 24mm Panoptic. So I'm looking forward to an opportunity to test that wide-field 1-1/4 inch eyepiece. It will not likely disappoint.

My new Panoptic 24mm, 1-1/4 inch eyepiece is a true joy to use. I can see now that it will be my most used eyepiece. Its expansive view makes go-to finding of objects with the Celestron-11 very easy. It even makes go-to alignment a snap. One centering of an alignment star in the Telrad is needed. Then the Losmandy G-11/Gemini-1 mount slews to subsequence alignment stars, which fall within the C-11's 0.88° FOV. Just an eyeball precision centering of alignment stars is good enough for go-to finding.

 

Part of my getting to know the new Panoptic was looking at the near first quarter Moon. Though the seeing wasn't perfect, the view with my AT115EDT refractor was truly stunning. The 1.92° FOV really presented the Moon as a globe in space. So as I moved the Moon to the edge of the field, I was expecting to see all sorts of unpleasant warping of its outline due to reputed distortion. The big surprise here was there was nothing to see - that is the Moon looked identical to what had been seen when it was centered. Maybe it was my APO refractor's 805mm focal length at work. But whatever the cause, I was pleasantly surprised.

 

When I slewed to the Orion Nebula, I found all three stars of Orion's Sword were easily within the FOV of the 115 mm refractor. Near the "Fish Mouth" part of the nebula, there were the 4 Trapezium stars as well as another 5 stars arrayed in the fish's jaws - all pin-point stars. Despite the nebula's low elevation in the direction of maximum light pollution, the DGM Optics NPB (Narrow Pass Band) filter fitted to a 2-inch Barlow provided a grand view with the Panoptic on the APO. Trading the Pan over to the C-11 added a couple more stars around the fish mouth. Even without the filter, the nebula was more curdled with the larger aperture. My C-11 is set up for 1-1/4 inch eyepieces only. So I can't easily use the 2-inch DGM NPB filter. But I do have an Orion OIII filter in 1-1/4 inch format that can be employed.

 

In summary - the Televue 24mm Panoptic is a real winner!

 

Best Regards,

Russ


Edited by Rustler46, Yesterday, 02:39 AM.

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