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Siebert Optics Siebert Optics 2" 36mm Observatory Series

5.0 (1 Reviews) Read Reviews Write Review
Brand Siebert Optics
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5.0 (Based on 1 Reviews) 100% of reviewers recommended this product.
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    1. wrose

      wrose New Member

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      Oct 11, 2008

      5.0 Siebert Optics 2 in., 36mm Observatory


      Detailed and crisp in all scopes; 20mm+ ER w/wide FOV; Light weight and compact.


      Minor reflection on very bright stars; Does not have a well finished appearance.


      Original review 6 Dec '06

      I've been using the 36mm for over a year now and judge eyepieces based on my tendency to grab them over other eyepieces in my collection. Some eyepieces just have a comfortable feel to them and you tend to go back to those first. Besides ergonomics I have to feel that the eyepiece will give me excellent viewing the majority of the time. That means the eyepiece has to compare better then average to the other eyepieces I own as well as what's currently available.

      IMHO the Siebert Optics 2", 36mm Observatory eyepiece is unparalleled in it's price range. That's not to say there aren't better eyepieces out there. There are a few but not for the price. Optically the eyepiece has excellent detail and contrast as well as excellent light transmission. The views are sharp and crisp in all the scopes I've tried it in. This eyepiece has one of the flatest fields from edge to edge on any 35mm around even in a fast DOB. There is some coma & edge aberration in a Newtonian but it has less coma & edge issues than a 35mm Panoptic in a fast DOB. The eyepiece is light weight, compact, has excellent eyepoint, doesn't tend to black out or 'kidney bean', and works well with a Barlow. Unlike several other low power eyepieces it has 20mm+ eye relief and even with a Big Barlow it still has great eye relief and the FOV is barely reduced.

      Bottom line is it's a great eyepiece for the money so until someone comes out with a better 35mm for under $200 this eyepiece will have a home in my EP case for a long time.

      Oct '08 Update:

      I've been using this eyepiece regularly for 3+ years now. I still find I use it more than any other commonly available eyepiece in the 35mm focal length range. On some occasions I may pull out a 35mm Masuyama or Clave but because these two are fairly rare and more expensive eyepieces, they don't live in my eyepiece case. Even at that, the Clave & Masuyama only provide a very slight improvement over the Siebert 36mm Observatory Series eyepiece that is difficult to see unless viewing conditions are excellent or better. The Zeiss A-34 planetary and TV 31mm Nagler will also out preform this eyepiece on a night with very good viewing conditions but at 3 times the cost, they make the Siebert 36mm Observatory a terrific buy.

      In the last 18 months I've found I use the Siebert 36mm Observatory Grade eyepiece in preference to the 41mm Panoptic or 40mm Paragon. The 36mm OG provides a slight increase in magnification with very close to the same AFOV and still retains image quality. In a 12.5" f/5 DOB, the Siebert 36mm preforms every bit as good as the 41mm Panoptic and actually has better edge performance, especially without a Paracorr.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No
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