24mm Panoptic vs 24mm ES 68 degree series

[bomberbaz]

The qualities of the Panoptic are well known and I have read many times on these forums reports of the eyepiece and how well rated it is.

The ES 24/68 is also supposed to be of very good quality and I am sure I remember reading that they are a kind of clone of the panoptic. The best kind of flattery.

Just wondered if anyone has ever done a side by side though, both good eyepieces so how do they compare.

[vlaiv]

How about this article?

https://www.cloudynights.com/articles/cat/user-reviews/24-26-mm-eyepiece-comparison-r2651

[John]

I owned the ES 24 / 68 and then got a 24 Panoptic. Very little in it in terms of performance, maybe nothing much of the time.

I just wanted another 24mm Panoptic though, after selling one a few years back and regretting it

 

 

 

 

[Second Time Around]

https://www.cloudynights.com/articles/cat/user-reviews/24-26-mm-eyepiece-comparison-r2651

This is a very comprehensive comparative review of a great many 24-26mm eyepieces, including the 2 you asked about, by Bill Pasolini.

[Space Hopper]

I've got a pair of 24Pans and they are my favourite eyepieces. Really nice glass.

I believe they are Tele-vues best selling eyepiece as well, which speaks volumes.

The ES 24/68 i'm sure is right up there as well, but i've never compared the two.

The Pans are better for me, as the have that taper below the eyecup, which makes them ideal for binoviewing (plenty of nose room !)

If you pick either, you won't go far wrong.....

[iPeace]

I have done so in the past. To my eyes, the ES was - for all practical purposes - just as good. I eventually chose to keep the Panoptic, as it is a bit more compact...but the green lettering probably meant more.

[John]

Just now, Second Time Around said:

https://www.cloudynights.com/articles/cat/user-reviews/24-26-mm-eyepiece-comparison-r2651

This is a very comprehensive comparative review of a great many 24-26mm eyepieces, including the 2 you asked about, by Bill Pasolini.

I think that is the same link that vlaiv posted earlier.

It is a good review though

[Second Time Around]

Sorry, lost the internet for a while and posted without checking there had been any more replies q in the meantime!

[Don Pensack]

I've compared the two of them along with the 24mm APM Ultra Flat Field (also available from Altair).

The only one compatible with glasses is the APM.

The best in a 12.5" f/5 scope was the Panoptic because the star images were the best at/near the field stop.

The ES at that f/ratio had too much astigmatism in the outer field.

The APM came close to the Panoptic, but did deteriorate right near the field stop.

In my f/7 Apo, though, the ES cleans up and only has a bit of astigmatism right near the field stop and the other 2 are essentially equal.

[Bill Paolini's scopes, it should be noted, are all f/8 or longer, so weight his reviews accordingly]

I didn't have a longer scope on hand, but given the difference between f/5 and f/7, I could pretty much guess that at f/8 or longer, all three would be essentially perfect.

 

One odd thing I would note: the APM seems to have a dead-flat field of view, like looking at a map.  The Tele Vue has a sharp field to the edge, but seems to be a bit "bowl-shaped"

as if the field is a tad curved--this is noted as the scope is panned while looking through the eyepiece.

I attribute this to about a 5.5% field distortion on the Panoptic compared to 0.27% in the APM..  The ES was ~4.7%

All had noticeable pincushion distortion when used in daylight on straight line targets like a telephone pole.

This was assuming the manufacturer's apparent field claims, which may or may not be accurate.  I did not measure the apparent fields exactly. 

Edited May 19, 2020 by Don Pensack

[Ags]

Never tried the Pan but I have no complaints about my ES 24/68. Well... They should have purged it with Helium not Argon to save some weight!

[Supernova74]

I’m not sure about the Exsplore scientific 24mm 68 degree being a clone of the panoptic however the Exsplore scientific 82 degree range apparently was a clone on the televue nagler series.the Exsplore scientific range of eyepieces are great value for money Argon,nitrogen purged what ever.and I’ve owned them there is something special about Televue eyepieces tho thinking it’s the intense design process strict quality control and anyone who owns them will most probably feel the same Televue concentrate on just eyepieces apart from a few APO scopes.if you got an Ferrari you don,t expect it to perform on mini tyres do you as the scope is just as important as the eyepiece you peak through the field of view is tack sharp to the very edge contrast admittedly more noticeable on higher end scopes  that’s why thay are considered the best Astronomical eyepieces in the world.so if you got the money why have satin when you can have silk as once owned will never need to upgrade your eyepiece collection again.

 

[bomberbaz]

When I posted this I was having some whimsical ideas regarding my eyepiece collection. I have for a while been thinking about adding a 24mm panoptic despite owning a 26mm nagler.

I do like a good collection of glass for my dob, the fast focal ratio kind of demands it but wasn't sure about the ES glass however @Don Pensackhas answered my query and I shall not pursue them further.

I shall stick with my collection as it is for now.

BTW I shall never part with my Nikons, I love them far too much. 

Steve

[Louis D]

21 hours ago, Don Pensack said:

One odd thing I would note: the APM seems to have a dead-flat field of view, like looking at a map.  The Tele Vue has a sharp field to the edge, but seems to be a bit "bowl-shaped"

as if the field is a tad curved--this is noted as the scope is panned while looking through the eyepiece.

I attribute this to about a 5.5% field distortion on the Panoptic compared to 0.27% in the APM..  The ES was ~4.7%

I measure the APM UFF 24mm to have a 63 degree AFOV using projection.  I measured the effective field stop to be 27.5mm, but it fuzzes out a bit, so it's hard to nail down exactly.  It's above the shoulder.  The effective AFOV (eAFOV) works out to be 66 degrees if you want to calculate the TFOV from the magnification times the AFOV.  Here's an image comparing the view through the 24mm APM UFF to others in that range.

And a diagram of the internal lenses (second from right):

The field stop is physically 30.2mm, but due to the Smyth lens, it works out to about 27.5mm as I said above.

It's a nice lens and all, providing the maximum field possible in a 1.25" eyepiece, but I still prefer the 22mm AT AF70 if I have a 2" focuser handy.  The fields are about the same (28.4mm FS for the AF70), but there is none of the fuzzing out at the edge like in the UFF due to the design pushing things a bit too far.  Both are equally easy to use with eyeglasses.

Edited May 20, 2020 by Louis D
Added colorized diagram per Don P's suggestion

[Don Pensack]

One day soon, if I ever see clear skies again, I'll do a true field test for the APM24 and derive a field stop diameter.

That can't derive an apparent field, since distortion is not known with any certainty, but I'll take your 63° as accurate enough.

BTW, the Altair Astro cross section diagrams are easier to see and count lenses in because of color:

https://www.altairastro.com/altair-30mm-ultraflat-eyepiece---precision-barrel-stainless-steel-238-p.asp

Click on the cross section image, then click on it again to get a large size version.

[rwilkey]

10 hours ago, bomberbaz said:

When I posted this I was having some whimsical ideas regarding my eyepiece collection. I have for a while been thinking about adding a 24mm panoptic despite owning a 26mm nagler.

Hi Steve, the great advantage in my opinion is that the 24 Pan is a 1.25", whereas the 26 Nag is not, that makes the 24 Pan very easy to use as 2" eps can be unwieldly and heavy, esp. for a smaller, lighter set-up, in other words, so I think it is more versatile.  Like John has intimated in the past, it also quickly became my favourite ep.

[bomberbaz]

2 hours ago, rwilkey said:

Hi Steve, the great advantage in my opinion is that the 24 Pan is a 1.25", whereas the 26 Nag is not, that makes the 24 Pan very easy to use as 2" eps can be unwieldly and heavy, esp. for a smaller, lighter set-up, in other words, so I think it is more versatile.  Like John has intimated in the past, it also quickly became my favourite ep.

Cheers Robin. If one came along at the right price I would be very tempted. I am very good at talking myself into buying eyepieces. 

[Captain Scarlet]

8 minutes ago, bomberbaz said:

Cheers Robin. If one came along at the right price I would be very tempted. I am very good at talking myself into buying eyepieces. 

I'll have to be quick on the buzzer then. I too am in the market for one

M

[rwilkey]

8 minutes ago, bomberbaz said:

I am very good at talking myself into buying eyepieces.

Hi Steve, I have noticed that in the past haha!  I also suffer from the same affliction.  Clear skies buddy!

[johnturley]

3 hours ago, rwilkey said:

Hi Steve, the great advantage in my opinion is that the 24 Pan is a 1.25", whereas the 26 Nag is not, that makes the 24 Pan very easy to use as 2" eps can be unwieldly and heavy, esp. for a smaller, lighter set-up, in other words, so I think it is more versatile.  Like John has intimated in the past, it also quickly became my favourite ep.

I agree, since acquiring a 24 mm Panoptic, I tend to use it in preference to my ES 24 mm 82 degree eyepiece, although the field of view is slightly smaller, the edge definition is better, and it is much lighter, so that I do not need to have to adjust one of the sliding balance weights on my 14 in Newtonian, which is very balance sensitive.

John  

[Louis D]

7 hours ago, rwilkey said:

Hi Steve, the great advantage in my opinion is that the 24 Pan is a 1.25", whereas the 26 Nag is not, that makes the 24 Pan very easy to use as 2" eps can be unwieldly and heavy, esp. for a smaller, lighter set-up, in other words, so I think it is more versatile.  Like John has intimated in the past, it also quickly became my favourite ep.

If you don't need the eye relief for eyeglasses, the 24mm Pan is probably the lightest option out there at 8.2 oz with good correction.  The 24mm APM UFF is 12.2 oz and the 22mm AT AF70 (2") is 16.8 oz.  Since I use mostly Delos/Pentax XL-XW/Morpheus, I'm already balanced for 12 oz to 16 oz eyepieces, so the latter two are not an issue for me.  It's when I put the ES-92s in that my balance really goes out.

[bomberbaz]

7 minutes ago, Louis D said:

If you don't need the eye relief for eyeglasses, the 24mm Pan is probably the lightest option out there at 8.2 oz with good correction.  The 24mm APM UFF is 12.2 oz and the 22mm AT AF70 (2") is 16.8 oz.  Since I use mostly Delos/Pentax XL-XW/Morpheus, I'm already balanced for 12 oz to 16 oz eyepieces, so the latter two are not an issue for me.  It's when I put the ES-92s in that my balance really goes out.

I use a dioptrix Louis so wouldn't be a problem. 

As for balance, all my glass is very weighty anyway, (see sig) so the scope is setup to use eyepiece plus a coma corrector or for high power when CC isn't needed I use eyepiece plus powermate. Overall weight is roughly the same.

[Don Pensack]

The 24mm Panoptic requires a TeleVue-made adapter to accept a DioptRx.

The APM takes it directly.

Either way.

[bomberbaz]

1 hour ago, Don Pensack said:

The 24mm Panoptic requires a TeleVue-made adapter to accept a DioptRx.

The APM takes it directly.

Either way.

thought i had one don, just checked and its the nagler 6 adaptor, thankfully they are not that expensive.

[bomberbaz]

On 19/05/2020 at 19:09, Don Pensack said:

I've compared the two of them along with the 24mm APM Ultra Flat Field (also available from Altair).

The only one compatible with glasses is the APM.

The best in a 12.5" f/5 scope was the Panoptic because the star images were the best at/near the field stop.

The ES at that f/ratio had too much astigmatism in the outer field.

The APM came close to the Panoptic, but did deteriorate right near the field stop.

In my f/7 Apo, though, the ES cleans up and only has a bit of astigmatism right near the field stop and the other 2 are essentially equal.

[Bill Paolini's scopes, it should be noted, are all f/8 or longer, so weight his reviews accordingly]

I didn't have a longer scope on hand, but given the difference between f/5 and f/7, I could pretty much guess that at f/8 or longer, all three would be essentially perfect.

 

One odd thing I would note: the APM seems to have a dead-flat field of view, like looking at a map.  The Tele Vue has a sharp field to the edge, but seems to be a bit "bowl-shaped"

as if the field is a tad curved--this is noted as the scope is panned while looking through the eyepiece.

I attribute this to about a 5.5% field distortion on the Panoptic compared to 0.27% in the APM..  The ES was ~4.7%

All had noticeable pincushion distortion when used in daylight on straight line targets like a telephone pole.

This was assuming the manufacturer's apparent field claims, which may or may not be accurate.  I did not measure the apparent fields exactly. 

Only just really picked up on this Don and did a google search on the APM. If this is the same eyepiece APM then it's coming in at a significant circa 50% saving on a tele vue panoptic.

I realise it isn't quite as good but at half price one must certainly consider ones options.

[Don Pensack]

Yes, you've identified it.

And I found it good enough in my f/7 apo that it became the eyepiece to extend the set of Tele Vue Delites I had in my case.

It was the only one of the 3 to be easily used with glasses, which I use on large exit pupil producing eyepieces.