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Are there any eyepieces with 5 lenses

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#1 Lucullus

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Posted 17 October 2020 - 05:33 PM

My recent search for 5 lens eyepieces was quite unsuccessful. Are there any 5 lens eyepieces on the market today at all?



#2 Benach

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Posted 17 October 2020 - 05:41 PM

Most Super-Plossls, despite the name, have five lenses and are in reality Erfles. The reason, I once heard, not confirmed, is that Erfle's name was associated with the German WW2 industry and thus called Super-Plossls for marketing purposes.

 

The Takahashi LE's are probably also having five lenses.


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#3 Couder

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Posted 17 October 2020 - 05:47 PM

types of eyepieces:

https://www.chuckhaw...ece_designs.htm

 

and this one mentions 5 elements

https://en.wikipedia.org/wiki/Eyepiece



#4 DLuders

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Posted 17 October 2020 - 05:50 PM

Erfle II 5-lens design.JPG    Galoc 5-lens design.JPG   Galoc II 5-Lens Design.JPG   Goerz 5-lens design.JPG    Takahaski 5-Lens Design.JPG    Zeiss 5-lens design.JPG


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#5 Benach

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Posted 17 October 2020 - 05:53 PM

Never seen a Galoc or Goertz eyepiece on the market, have you?



#6 sixela

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Posted 17 October 2020 - 06:27 PM

No, but the Takahashi LE and Zeiss Astroplanar-like designs have been on the market quite a lot (he said, jealously eyeing his neighbour's excellent 35mm Celestron Ultima).

So have "real" Erfles, of course, even though the advent of fast scopes have made them less and less popular.

And let's not forget that telescopes are not the only consumers of eyepieces...

Edited by sixela, 17 October 2020 - 06:30 PM.

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#7 luxo II

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Posted 17 October 2020 - 06:42 PM

Vixen LV, NLV and SLV were 5 element designs...



#8 SandyHouTex

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Posted 17 October 2020 - 06:55 PM

Yes.  There are also the Zeiss Astrplanokulars (sp?), Masayamas, and pseudo-Masayamas.


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#9 rowdy388

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Posted 17 October 2020 - 07:10 PM

Of the more than two dozen eyepieces in my current stable, there is only one with five lenses,

the 32mm Masuyama 85. 


Edited by rowdy388, 17 October 2020 - 07:12 PM.


#10 Jon Isaacs

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Posted 17 October 2020 - 07:14 PM

Some of the Paradigms/Starguiders have 5 elements.. the 25mm, 18mm, 8 mm , 5 mm, 3.2 mm. 

 

Jon


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#11 sixela

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Posted 17 October 2020 - 07:18 PM

Yes.  There are also the Zeiss Astrplanokulars (sp?),

In addition to the Astroplanokulars in the last image, you mean ;-) ?
 

Masayamas, and pseudo-Masayamas.

I think that name is spelled "Masuyama" - and those designs are very close to the Zeiss Astroplanokular, I think (not identical, of course -- glass types have evolved over time, and it would have been foolish to stick with 1955 formulas). So much so that some of them were actually sold as "Astroplan" eyepieces.

Edited by sixela, 17 October 2020 - 07:22 PM.

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#12 Benach

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Posted 17 October 2020 - 07:43 PM

And let's not forget that telescopes are not the only consumers of eyepieces...

 

Neither have I seen them in some of the other optical equipment I know. But hey, I'd be happy to see one in real life.



#13 Obx

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Posted 17 October 2020 - 07:49 PM

The pseudo-Masuyama plossls (under many brand names) from the early 1990s had five lenses. I own one: a Meade Super Plossl made in Japan by Kowa before Super Plossls switched to four lenses (also made in Japan and then in China). 


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#14 izar187

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Posted 17 October 2020 - 08:25 PM

https://www.sieberto...rtho page).html



#15 SeattleScott

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Posted 17 October 2020 - 08:43 PM

There are tons of five element eyepieces. Most of them are cheap and don’t perform well in fast scopes. Maybe search for 5-element eyepieces.

Scott

#16 BFaucett

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Posted 17 October 2020 - 09:02 PM

My recent search for 5 lens eyepieces was quite unsuccessful. Are there any 5 lens eyepieces on the market today at all?

 

See Don Pensack's spreadsheet. It's an Excel file. It can be found here:

 

2020 Eyepieces Buyer's Guide

https://www.cloudyni...2#entry10103883

 

Bob F.

 


Edited by BFaucett, 17 October 2020 - 09:17 PM.


#17 BillP

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Posted 17 October 2020 - 09:18 PM

As Jon mentioned: 25mm, 18mm, 8 mm , 5 mm, 3.2 mm Paradigm Dual ED / BST Starguiders (same eyepiece different branding)

 

The premium build and optics of the Tak LEs in 24mm, 18mm, 12.5mm, 10mm, 7.5mm, and 5mm are also all 5 elements.

 

Bresser has a 20, 26, and 32mm 5-element Plossl - https://www.bresser....eces/60-Series/

 

Takahashi also has a 28mm Erfle

 

GSO Superviews in 50mm, 42mm, 30mm, and 20mm

 

Agena Enhanced Superwide in 6mm

 

Tele Vue Nagler Zoom in 2-4mm and 3-6mm

 

Orion Q70 in 26mm, 32mm, 38mm


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#18 BKSo

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Posted 17 October 2020 - 09:21 PM

Apm uff 10
Tmb planetary clones
Vixen HR

#19 Peter Besenbruch

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Posted 17 October 2020 - 09:46 PM

Most Super-Plossls, despite the name, have five lenses and are in reality Erfles. The reason, I once heard, not confirmed, is that Erfle's name was associated with the German WW2 industry and thus called Super-Plossls for marketing purposes.

 

The Takahashi LE's are probably also having five lenses.

All current super-Plössls are 4 element designs. The common 5 element designs are Erfles and Astroplans. The original super-Plössls from Meade were Astroplan designs. Likewise the current Tak LEs.


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#20 luxo II

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Posted 17 October 2020 - 09:53 PM

Apm uff 10

Interesting choice.

Attached Thumbnails

  • post-269196-0-66126600-1510470581_thumb.png

Edited by luxo II, 17 October 2020 - 10:01 PM.

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#21 Astrojensen

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Posted 18 October 2020 - 02:14 AM

Don't forget the Masuyama 85's: 32mm, 26mm, 20mm, 16mm and 10mm. 

 

These are NOT low-budget eyepieces, BTW... Still f/ratio sensitive and prefers f/10 or longer. 

 

 

Clear skies!

Thomas, Denmark


Edited by Astrojensen, 18 October 2020 - 02:16 AM.

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#22 noisejammer

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Posted 18 October 2020 - 06:37 AM

... The premium build and optics of the Tak LEs in 24mm, 18mm, 12.5mm, 10mm, 7.5mm, and 5mm are also all 5 elements. ...

 

Bill, I think the Tak 5 & 7.5 LE are really longer Erfle's with a built in Smyth lens, so they have 7 elements. I have pairs of each and they're great for shallow space.
 



#23 j.gardavsky

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Posted 18 October 2020 - 06:58 AM

The original Astroplanokular design (like that of Erfle) employs 5 different glass materials, including the achromatizating combination of BK7 with F2 (or F4), and all lens surfaces having different curvatures.

 

See for comparison one of the Erfle designs, https://spie.org/pub..._eyepiece?SSO=1

which mentions the lateral CA compensation in dependence if a zenith prism in OTA will be used or not.)*

 

When optimally designed and made, these eyepieces are no way cheap, as the tactical f=40mm AFOV=70° by Rodenstock, illustrates.

 

Best,

JG

 

PS:

)* This defeats the repeated and unfortunately widespread claims by some people, that the eyepiece designs can't compensate the lateral CA.


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#24 25585

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Posted 18 October 2020 - 07:31 AM

Now which is the best 5 lens arrangement & for what?

 

2-2-1, 2-1-2, 1-2-2, 3-1-1, 1-3-1, 1-1-3, 4-1, 1-4,  3-2, 2-3, 5-0....?



#25 Astrojensen

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Posted 18 October 2020 - 09:56 AM

Now which is the best 5 lens arrangement & for what?

 

2-2-1, 2-1-2, 1-2-2, 3-1-1, 1-3-1, 1-1-3, 4-1, 1-4,  3-2, 2-3, 5-0....?

There is no best arrangement, it all depends on the actual design and execution. 

 

There are even more possible combinations than the ones you listed, BTW. 

 

 

Clear skies!

Thomas, Denmark


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