Siebert Optics - Observatoy series

2" has a 65 deg. FOV and 20mm's eye relief.

Compact in size and only 9 oz.

No "Blacking out" or "Pin Cushioning"

2" is $229 (Ob236mm) Brass add $70*

35mm Pan vs. Siebert Observatory 36mm. Both are sharp to the edge in fast scopes but the OB wins on pin cushioning and it also has eye relief that people with eye glasses will appreciate. >>>>>>>>>>>>>>>>

All Observatory. eyepieces are under 9 oz.

Were did the Observatory Series eyepieces come from. Click here

Large optics reduce apparent vignetting.

Click on picture to enlarge. Here is the eyepiece comparisons page.

Observatory eyepieces are known for their excellent edge correction. The 34mm and 36mm are sharp to the edge at f5 and very good at f4.5 without a Paracorr.

2" 34mm Eyepiece

2" has a 65 deg. fov and 20mm's eye relief.

Compact in size and only 9 oz.

No "Blacking out" or "Pin Cushioning"

2" is $229 (Ob234mm)Brass add $70*

All Observatory. eyepieces are under 9 oz.

Large optics reduce apparent vignetting.

Click on picture to enlarge. Here is the eyepiece comparisons page.

Observatory eyepieces are known for their excellent edge correction. The 34mm and 36mm are sharp to the edge at f5 and very good at f4.5 without a Paracorr.

Observatory Elite

This line has many professional and amateur applications

See complete list below.

Click on pictures below.

2.5"/2.7"/3"/50-70mm

4" 50mm - 110mm

4.3" 50mm - 110mm

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2.5" 50-70mm $999 (Brass) add $199* .

For Istar and like F10-F15 .

All have 25mm E.R.

All have a 60mm F.S.

The 2.5" 50mm 70 deg FOV

The 2.5" 55mm 63 deg FOV

The 2.5" 60mm 57 deg FOV

The 2.5" 65mm 53 deg FOV

The 2.5" 70mm 50 deg FOV

2.5 lb

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2.7" 50 -70mm $999 (Brass) add $299* .

All have 25mm E.R.

All have a 66mm F.S.

The 2.7" 50mm 70 deg FOV

The 2.7" 55mm 65 deg FOV

The 2.7" 60mm 60 deg FOV

The 2.7" 65mm 56 deg FOV

The 2.7" 70mm 52 deg FOV

3.1lb

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3" 50 -70mm $1199 (Brass) add $299*

All have 25mm E.R.

All have a 67mm F.S.

The 3" 50mm 70 deg FOV

The 3" 55mm 70 deg FOV

The 3" 60mm 63 deg FOV

The 3" 65mm 58 deg FOV

The 3" 70mm 55 deg FOV

3.5lb

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4" 50-110mm $1399 (Brass) add $499*

4.3" 50-110mm $1399 (Brass) add $499*

All have 25mm E.R.

If your scope has to carefully manage focus in-travel please give me details on the limitations of your scopes focus.

All have a No F.S.

50mm AFOV 70deg

55mm AFOV 70deg

60mm AFOV 70deg

65mm AFOV 65deg

70mm AFOV 65deg

75mm AFOV 60deg

80mm AFOV 60deg

85mm AFOV 57deg

90mm AFOV 55deg

95mm AFOV 55deg

100mm AFOV 55deg

105mm AFOV 55deg

110mm AFOV 55deg

Observatory Elite 80mm 4 inch eyepieces are 6 element. They are fully anodized Grey.

This 80mm 4" eyepiece was sent to the Mount Wilson observatory in 2007 for use in their 60" Cas See it in use in link below. E.P. info here.

All pictures used are with the permission of owner. http://www.icstars.com/HTML/Events/MtWilson60/index.html Click pictures below.

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How about this 70mm 4.3" 70 deg eyepiece that was sent to the Carnegie Institution of Washington in 2010 for their 6.5 meter or ( 234") Magellan. Link to Observatory below.

http://www.lco.cl/telescopes-information/magellan/instruments/telescopes-information/magellan/

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How about this 110mm 4.3" 55 deg 10 lb eyepiece that was sent to the University of California for the Lick Observatory in 2013 for their 36" 3 story Historic Refractor.

Link to Observatory below.

http://www.ucolick.org/

http://en.wikipedia.org/wiki/Lick_Observatory

This eyepiece come with top and bottom dust caps.

You can get the Optional eyepiece projection camera adaptor. Details below.

This replaces the top dust cap and has a 2" dia opening and a 2" to 1.25" step-down. This will let you use 2" and 1.25" format camera setups.(T-2 is also available) So if you want to do eyepiece projection photography, this makes it easy to attach your camera to the eyepiece with little or no additional hardware. This option costs $99

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2.7" and 3"eyepieces

These 2.7" and 3"eyepieces are for Large and Backyard Observatory Telescopes alike. Camera adaptor now Optional.

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4 " and + size Eyepieces

The above 80mm is used at the Mount Wilson Observatory in California. Here the 80mm Elite is compared to a 40mm Pentax XL. And below shows the optional mounted on camera adaptor.

The above 70mm 4.3" eyepiece is used in the 24 Foot Dia Magellan in Chile.. picture above.

This 90mm Elite was sent to Herold Observatory, Onalaska School District, WA as part of an Astro-Physics 4.3" focuser upgrade for their 24" Cassegrain.

Here is the 4.3" Focuser on their site. Click Here.

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100mm Elite was sent to South Korea. Scope to be used unknown. More when feedback is available.

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The Elite series eyepieces on your scopes.

4.3" / 4 "/ 3" /2.7" and 2.5" Eyepieces Some of these eyepieces can even be used in long F.L. backyard Observatory scopes. The eyepieces below will give you at least twice the amount of sky possible for your largest field stop 2" eyepieces.

10" - 60" and much larger Cassegrain scopes.

5" and larger long F.L. Refractors.

EX: 6" f15 Refractor F.L. 2268mm

------------Here is the Elite difference.-----------------------

(55mm 2" TV Plossl) and it's 46mm Field Stop has a 1.14deg True FOV.

(65mm 3" Elite) and it's 67mm F.S. now has a 1.66deg True FOV.

Now that sounds like only about 33% gain in true FOV but the amount of sky you are now covering about 1.5x greater. This will hold true for any scope you use. More facts below.

-----Will you have problems with your Exit Pupil. Look Below.-------

Exit Pupil with 3" 65mm at F15 is = 4.3mm --Great

Exit Pupil with 3" 65mm at F12.5 is = 5.2mm --Great

Exit Pupil with 3" 65mm at F10 is = 6.5mm --Not Bad

Click on eyepiece pictures below to enlarge.

What scopes can use the 50mm-110mm? Many CCD chips will benefit from the 40mm-50mm eye lens and huge optics of these eyepieces. In fact it may be the lowest possible power photo you could take through your scope with eyepiece projection imaging.

2.5" 2.7" 3" Diagonals

Diagonal optical path 6"

2.5" Diagonals

2.7" Diagonals

3" Diagonals

Hybrids below.

2.5" inlet to 2.7" outlet

2.5" inlet to 3" outlet

2.7" inlet to 3" outlet

All Anodized. $1199

Any Adaptor you wish for the above diagonals. $99 each

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