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Panoptic 19,24 mm or Delite 18.4mm

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#1 GR1973

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Posted 27 May 2017 - 02:28 PM

I have full set of Brandon eyepieces. I bought 11 mm Delite and found it little brighter than Brandon's. Now I want to add another eyepiece in my low power area. Many people recommend 19 mm Panoptics ( This is before the existence of Delite)
My question is which is better and more sharp the 19 mm panoptic or 18 mm Delite?
Also, what about 24mm Panoptic?
Please give me your opinions.

All the best

#2 Larry Geary

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Posted 27 May 2017 - 03:56 PM

The advantage of the 19mm Panoptic is that it comes to focus with the Questar finder. I don't know about the other two. I've never tried a Delite, but I find Televue's modern eyepieces to be shockingly good.


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#3 Optics Patent

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Posted 27 May 2017 - 05:06 PM

Technical question: if the finder and main optics both form images in the same plane to be viewed by a Questar Brandon in focus, why would any other eyepiece not see them both in focus?

#4 Loren Gibson

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Posted 27 May 2017 - 05:48 PM

Technical question: if the finder and main optics both form images in the same plane to be viewed by a Questar Brandon in focus, why would any other eyepiece not see them both in focus?

There's a limit to the travel of the eyepiece holder for focusing the finder scope. Therefore, if the eyepiece's field stop is to far from, or too close to, the location where the eyepiece seats, it can't be threaded out or in (respectively) far enough to focus the finder. On the other hand, the main scope's focus mechanism can place the focal plane in a wide range of positions along the optical axis. Hope this makes sense.

 

Edit and rephrasing: The location of the focal plane of the finder scope is fixed in position. You have to move the eyepiece in and out to bring the finder to focus. If the eyepiece field stop is too deep or two shallow in the barrel, there isn't enough focus travel to bring the finder into focus. Note that throwing the barlow into the optical path poses the same problem, because it will push the focal plane too far from the finder objective.


Edited by Loren Gibson, 27 May 2017 - 05:52 PM.

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#5 Optics Patent

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Posted 27 May 2017 - 07:45 PM

 

Technical question: if the finder and main optics both form images in the same plane to be viewed by a Questar Brandon in focus, why would any other eyepiece not see them both in focus?

There's a limit to the travel of the eyepiece holder for focusing the finder scope. Therefore, if the eyepiece's field stop is to far from, or too close to, the location where the eyepiece seats, it can't be threaded out or in (respectively) far enough to focus the finder. On the other hand, the main scope's focus mechanism can place the focal plane in a wide range of positions along the optical axis. Hope this makes sense.

 

Edit and rephrasing: The location of the focal plane of the finder scope is fixed in position. You have to move the eyepiece in and out to bring the finder to focus. If the eyepiece field stop is too deep or two shallow in the barrel, there isn't enough focus travel to bring the finder into focus. Note that throwing the barlow into the optical path poses the same problem, because it will push the focal plane too far from the finder objective.

 

Got it.  While the finder has limited compliance and requires a "normal" focus position of the eyepiece, unusual eyepieces require extreme focus deviations in the main optics to achieve focus, and the finder range doesn't accommodate this.

Which raises the question: If you have to focus the main system outside of its designed range to focus at infinity, aren't you possibly de-optimizing a system designed for infinity focus with normal eyepieces?



#6 John F

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Posted 28 May 2017 - 10:35 PM

The 24mm Panoptic has a 27mm field stop.  The 24mm Brandon (the standard low power/wide field eyepiece that comes with the Questar) has a field stop of around 21.5mm.  The 19mm Panoptic has a field stop of 21.3mm and the 18.3mm DeLite has one of 19.1mm.

 

I believe that the way the Questar is made it cannot take advantage of any eyepiece that has a field stop much larger than the 21.5mm one that the 24mm Brandon has, hence a 24mm Panoptic made not be able to display a much larger field than the 24mm Brandon can.  I think that is why the 19mm Panoptic is the most popular Tele Vue alternative to the 24mm Brandon rather than the 24mm Panoptic which logically should be occupying that role if the Questar were able to take full advantage of it very wide (for a 1.25-inch eyepiece) 27mm field stop.  

 

The 19mm Panoptic works superbly with the Questar.  I used one with mine for several years and I can highly recommend it.  However, it only has 13mm of eye relief (which is about ideal if you don't need to be wearing eyeglasses when observing with the Questar).  The main advantage that the 18.2mm DeLite offers vis-a-vis the 19mm Panoptic is that it has 20mm of eye relief.  It is the low power eyepiece that I use now with my Questar and it also works quite well with it.  When I use it in "finder mode" it works well enough to easily enable me to find the moon or a planet with it and then center it in the finder mode field and then switch back to regular observing mode and then the object will either be in the field of very close to it and I can be usually find it quickly by moving the scope up or down or left or right.  I have not tried using the 18.2mm DeLite in finder mode to locate a deep sky object so I can't say one way or the other how well it might work for that.  I only use my Questar telescope for terrestrial observing during the day and for the moon and planet observing during the night. 

 

The bottom line, if you don't need to wear eyeglasses while observing the 19mm Panoptic is a superb choice.  However, if you do need to wear eyeglasses (or if other people who you allow to view through your Questar do need to wear eyeglasses) then the 18.2mm DeLite is the better choice. 

 

Incidentally, if you use the Questar's 1.5x built-in barlow, that converts the 19mm Panoptic to the equivalent of a 12.7mm Panoptic.  Or if you use it with the 18.2mm DeLite that turns it into the equivalent of a 12.1mm DeLite.  With my Questar I use the 18.2mm DeLite (at 70.3x), a 15mm DeLite (at 85.3x), and a 13mm DeLite (at 98.5x).  But when used with the Questar's 1.5x built-in Barlow, the 18.2mm gives me 105.5x, the 15m gives me 128.0x, and the 13mm gives me 147.8x.  At everyone of these powers I enjoy the advantage of having 20mm of eye relief, a 62mm apparent field (huge compared to a Brandon eyepieces), superb image quality and tack sharpness to the extreme edge of the field.   

 

If and when I ever sell my Questar the 24mm & 16mm Brandon eyepieces that came standard with it (and which still work pretty well) will go with that scope but I'll keep the DeLites and continue to use the with my other scopes.

 

John Finnan

 


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#7 GR1973

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Posted 29 May 2017 - 05:51 AM

John
Thank you so much for your detailed answer
I would like to give you some extra information
In my 24 mm Brandon field stop is only 18.21 mm
I do not use it so much and I like the 32 mm Brandon that gives 1.13 degree actual field. I use it with and without my glasses. I do not like the narrow field of the 24 mm Brandons (0.82) degree.
Finally, I have 1.63 built in Barlow.

Do these information change your answer?
What about the difference in contrast and sharpness between the 18 Delite and 19 panoptic??

My best regards

#8 Panotaker

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Posted 29 May 2017 - 06:28 AM

The advantage of the 24mm Panoptic is that it is the perfect eyepiece for doing a polar alignment using the Painless Polar Alignment method as described in the File's section of the Questar Yahoo group. If Kochab is at 3:00 o'clock in relation to Polaris, adjust your wedge until Polaris is right outside the field of view at 3:00 o'clock using the 24mm Pan, and you will be perfectly Polar aligned. Piece of cake, and only takes about a minute.


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#9 John F

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Posted 29 May 2017 - 11:27 PM

GR1973, on 29 May 2017 - 03:51 AM, said:

John
Thank you so much for your detailed answer
I would like to give you some extra information
In my 24 mm Brandon field stop is only 18.21 mm
I do not use it so much and I like the 32 mm Brandon that gives 1.13 degree actual field. I use it with and without my glasses. I do not like the narrow field of the 24 mm Brandons (0.82) degree.
Finally, I have 1.63 built in Barlow.

Do these information change your answer?
What about the difference in contrast and sharpness between the 18 Delite and 19 panoptic??

My best regards

No, if you don't need to wear eyeglasses while observing then I would recommend the 19mm Panoptic over the 18.2mm Delite for use as your low power eyepiece.  It definitely provides more of a subjective "wide field" experience than the 18.2mm DeLite does.  The difference between the two is not radical, but certainly quite noticeable and in favor of the 19mm Panoptic.  However, the overall image quality across the entire field is a little better in DeLite eyepiece than it is in the Panoptic.  Nevertheless, the 19mm Panoptic still shows a very fine image and if I did not now need to wear eyeglasses now when observing, then I would still be using the 19mm Panoptic as my low power/widest true field eyepiece with the Questar.

 

With regard to the 24mm Panoptic, if you use your Questar's motor drive (I don't) and need to polar align then maybe that eyepiece would be you best choice overall even through it is likely that not all of the field that it could potentially show you (if you were using a different scope) will be visible with the Questar.  Nevertheless, it should still be able to show you a true field at least as large as any of the other eyepiece alternatives (i.e., 24mm or 32mm Brandons, 19mm Panoptic, 18.2mm DeLite).

 

Incidentally, another DeLite eyepiece that might work very well with you particular scope is the 15mm DeLite which will give you 85x when it is used without the Questar's built-in Barlow but when used with your Questar's 1.63x Barlow it will give you 139x.

 

With regards to the 24mm Brandon eyepiece I've never heard of one that had a smallish (for that focal length) 18.21mm field stop.  Is the 24mm eyepiece that you're using a "Brandon" or "Questar-Brandon" or does it just say 24mm Questar?  Prior to contracting out eyepiece making work to Vernonscope in the early 1970s Questar used to make their own eyepieces and I wonder if the 24mm one that you've got might be one of those.

 

John Finnan


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#10 GR1973

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Posted 30 May 2017 - 04:43 AM

Thank you John
I will go for the 19 Panoptic. Most of the I observe in Alt/Az mode.
Regarding of my 24 Brandon, I purchased my scope from company 7 in late 2007. They provided me a sheet including all the specs of my scope and eyepieces. This is what have been written.
After reading some posts about other members 24 Brandon's, I measured the field stop of mine and found it around 18 mm so Company 7 is right

My Eyepieces are Questar Brandons and my scope was made in 2007.

Thank you

All the best
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#11 munirocks

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Posted 07 June 2017 - 11:18 AM

The advantage of the 24mm Panoptic is that it is the perfect eyepiece for doing a polar alignment using the Painless Polar Alignment method as described in the File's section of the Questar Yahoo group. If Kochab is at 3:00 o'clock in relation to Polaris, adjust your wedge until Polaris is right outside the field of view at 3:00 o'clock using the 24mm Pan, and you will be perfectly Polar aligned. Piece of cake, and only takes about a minute.

I'm looking at the Wikipedia article on Beta Ursea Minoris (Kochab). Kochab and Polaris are on opposite sides of the North Celestial Pole. Wouldn't this mean that with the Dec on your scope set to 90 and Kochab at 3:00 (way outside the main field of view) then you would need to adjust the wedge to put Polaris at 9:00 just outside the main field of view? Or is your use of  "3:00" ambiguous because you are comparing two different views, one of which is flipped left-to-right?



#12 Panotaker

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Posted 09 June 2017 - 03:22 PM

Painless Polar Alignment method is explained in the article that is in the files section in the Questar Yahoo Group. They have a little chart that shows you where to put Polaris in relation to Kochab. Since on most Questars the image is reversed, you have to account for that. I suggest you read that article, they explain it better than I can. Once you figure out how it works, it is very accurate. In the article, they suggest using a 32mm Brandon eyepiece, but the wide field of the 24 Panoptic is just as accurate.


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#13 RichA

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Posted 09 June 2017 - 11:40 PM

I have full set of Brandon eyepieces. I bought 11 mm Delite and found it little brighter than Brandon's. Now I want to add another eyepiece in my low power area. Many people recommend 19 mm Panoptics ( This is before the existence of Delite)
My question is which is better and more sharp the 19 mm panoptic or 18 mm Delite?
Also, what about 24mm Panoptic?
Please give me your opinions.

All the best

Panoptic 19mm is a near-perfect eyepiece. Very comfortable to look though, sharp and not huge.


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#14 NC Startrekker

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Posted 10 June 2017 - 09:00 AM

Panoptic 19mm is a near-perfect eyepiece. Very comfortable to look though, sharp and not huge.

 

 

 

I agree completely. My 24mm Brandon is feeling a bit lonely and under appreciated. I almost exclusively reach for the 19mm Pan instead. Alan


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#15 JimK

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Posted 16 June 2017 - 01:07 PM

 

Panoptic 19mm is a near-perfect eyepiece. Very comfortable to look though, sharp and not huge.

 

I agree completely. My 24mm Brandon is feeling a bit lonely and under appreciated. I almost exclusively reach for the 19mm Pan instead. Alan

 

Everyone has different preferences...

 

I enjoy using the 19mm Panoptic for star fields, with its apparent wide field to appreciate star clusters and bright nebulae, as well as the convenience of switching in a Barlow to see any additional detail.  Sometimes I use the 19mm Panoptic with a 2.5x PowerMate to split close doubles, but more often I use a 12mm (Brandon or Koenig, depending on the amount of starfield I want to see) with the internal Barlow.

 

However, I have found that the 24mm Brandon provides my best views of our Sun, with an ability to zoom in on sunspot detail using the Barlow switch.  The view from the 19mm Panoptic is less satisfying, probably because of both daytime atmospheric turbulence and the larger apparent size of the solar disk.  The same applies to those times when I view a full Moon (generally with a dark blue filter that allows me to easier see the bright lunar objects).

 

So I use different eyepieces depending on what I am viewing, as I suspect many observers do, but none of my eyepieces seem "lonely and under appreciated" -- it just depends on what I feel they are best suited for when observing.



#16 Optics Patent

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Posted 16 June 2017 - 02:31 PM

Yesterday when driving on the highway in the DFW area, I saw a beautiful white BMW 650i convertible.  It had a racing style adjustable black spoiler bolted to the trunk lid.  No matter how much it might improve performance, it just didn't look right.

I feel the same way about fitting a Questar with a giant eyepiece with big overhangs and green logos.

 

That said, my mind is open to giving them a try, and if proven superior I might just be happy to use one in the privacy of my back yard (not sure about the front yard).


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#17 RobertPettengill

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Posted 16 June 2017 - 09:09 PM

Brandon has made changes to the field stop size over the years in their eyepieces.  

 

I'm a fan of the 19mm Panoptic as well - about the same FOV as the 24mm Brandon but with with an immersive  larger apparent FOV.  My other favorite non Questar eyepiece is the 10mm Delos.  It also comes to a normal vision focus in the Questar finder.  The 10mm Delos gives a fantastic view of the full lunar disk which just fits inside it's FOV allowing you to scan the entire terminator in one view.

 

;rob



#18 GR1973

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Posted 06 March 2021 - 05:11 AM

Despite this is an old post and I am very happy with my Panoptic 19, I found this video to be useful for Questar's new owners as an answer

 

 

https://youtu.be/GJ1ZcYxnARk



#19 Mike Allen

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Posted 06 March 2021 - 09:12 AM

I think John F in the posts above pretty much nailed it.  I have both the 18.2 Delite and Panoptic 19, and have used both in the Q 3.5.  Both are really good oculars and the differences are minimal.  The Panoptic has a little wider apparent field, a little smaller and lighter, and eye relief a little too short for my glasses. The Delite has adequate eye relief for glasses, and can accept Dioptrix without an adapter, but a lot larger. They are both very sharp optically.  Both came to focus in the Q finder, but the Panoptic had a little more focusing tolerance.  I use the a Delite with a Dioptrix mostly in a fast scope where astigmatism is a factor, and the Panoptic in slower scopes such as the Q.  
 

Like Optics Patent, I feel there is not something quite right about sticking a big hulking eyepiece into a Q.  The Brandons also accept the winged eye guards I like to use to block ambient light pollution and improve contrast with deep sky objects.  I’ve tried different eyepieces with the Q, but Brandons provide the most pleasing image for me.



#20 Les Aperture

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Posted 06 March 2021 - 06:34 PM

Yesterday when driving on the highway in the DFW area, I saw a beautiful white BMW 650i convertible.  It had a racing style adjustable black spoiler bolted to the trunk lid.  No matter how much it might improve performance, it just didn't look right.

I feel the same way about fitting a Questar with a giant eyepiece with big overhangs and green logos.

 

That said, my mind is open to giving them a try, and if proven superior I might just be happy to use one in the privacy of my back yard (not sure about the front yard).

We refer to those aftermarket trunk lid "spoilers" as; push handles...

Young kids think they are in a "Fast & Furious" movie.

They are basically not worth the time, except to lighten your wallet.

 

Anyone have a photo of an Ethos in the Q? Woof.


Edited by Les Aperture, 06 March 2021 - 06:35 PM.


#21 davidmcgo

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Posted 06 March 2021 - 11:47 PM

We refer to those aftermarket trunk lid "spoilers" as; push handles...

Young kids think they are in a "Fast & Furious" movie.

They are basically not worth the time, except to lighten your wallet.

 

Anyone have a photo of an Ethos in the Q? Woof.

Agree 100%!

 

On TeleVue’s web site

 

https://televue.com/..._page.asp?id=60

 

This looks so unbalanced I would hate to do that to my scope.  Probably wear out the disks in real short order dragging that heavy eyepiece around.

 

Dave



#22 JamesMStephens

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Posted 07 March 2021 - 09:01 AM

This review has a pic of a Q3.5 Duplex with the 19 mm Panoptic  http://www.scopeview...k/Questar35.htm

 

Jim


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#23 Simoes Pedro

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Posted 03 April 2021 - 12:07 PM

The advantage of the 19mm Panoptic is that it comes to focus with the Questar finder. I don't know about the other two. I've never tried a Delite, but I find Televue's modern eyepieces to be shockingly good.

In depends on the Questar. On mine, even the thread-on brandons have a hard time reaching focus in the finder. In addition, the finder is only useful for the moon, planets and bright stars, where it does not make a difference whether it is in focus or not.

 

Pan 19 and DeLite 18.2 are both parfocal group B, in TV catalogue. My 18.2 DeLite is way off from reaching focus. I must assume a 19 Pan would be as well, in mine at least.

 

The DeLite 18.2 has the advantage of being heavier, better offsetting the "front heaviness" of the Q3.5, and has better eye-relief. The Pan 19 has marginally wider field, but shorter eye-relief. I would not choose based on true field, because it is not the extra 2.2 mm of field-stop that will transform the Q into a wide field telescope.

 

I do not think you can go wrong with either of them. I really wished the 24 Pan could fit the Q, but that is another story...



#24 Mike Allen

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Posted 04 April 2021 - 10:00 AM

In addition, the finder is only useful for the moon, planets and bright stars, where it does not make a difference whether it is in focus or not.

 

Perhaps in an urban environment.  My sky has a naked eye limiting magnitude of 5.5 near the zenith.  As a result, the finder in my Q 3.5, using the 16 mm Brandon, easily reaches magnitude 7 stars.  I find this adequate for navigation by star hopping while using a Interstellarum Star Atlas. The finder goes much deeper at my favorite dark sky site.


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#25 Opie Taylor

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Posted 28 April 2021 - 06:49 PM

Yesterday when driving on the highway in the DFW area, I saw a beautiful white BMW 650i convertible.  It had a racing style adjustable black spoiler bolted to the trunk lid.  No matter how much it might improve performance, it just didn't look right.

I feel the same way about fitting a Questar with a giant eyepiece with big overhangs and green logos.

 

That said, my mind is open to giving them a try, and if proven superior I might just be happy to use one in the privacy of my back yard (not sure about the front yard).

I got my Q to initially sit on the piano in the living room and look pretty - as a beautiful display piece - (until I found out how easy it is to use....).  

And on that note  - for display purposes -  I have found that the old Celestron silver-top 26mm plossl is a perfect match - - - (and gives decent views too....). 

 

https://www.flickr.c...posted-public/ 

 

https://www.flickr.c...osted-public/  




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