Jump to content


Photo

Siebert Elite 45 2" Binoviewers and Fast Newts

  • Please log in to reply
10 replies to this topic

#1 Bob S.

Bob S.

    Surveyor 1

  • *****
  • Posts: 1835
  • Joined: 14 Jul 2005

Posted 27 July 2014 - 05:36 PM

It is hard to know where to start the tale. About a year and a half ago I obtained the Holy Grail of binoviewers, a pair of Siebert Elite 45's. They have the largest mirrors (45mm) of any binoviewers, use 2" eyepieces and now have a newly developed multi-mag (1.3x and 2x) OCA that corrects the images for coma down to a blazing fast f/2.7

Thursday night at Chiefland Astronomy Village in Central Florida was predicted and turned out to be a great night. Seeing was about a 8/10 and transparency was about 7-8/10. I had rushed down after work to uncover my 32" f/3.66 Newtonian and turned on the internal (3) fans and placed a 20" box fan blowing on the primary. The scope is enclosed in a temperature moderated enclosure and the ambient and large primary/secondary equilibrated rather quickly.

My goal was to use my newly collimated (apparently, they had slightly decollimated with the first owner for some reason) Sieberts with a brand-new 2" optical corrector that was designed for our uber-fast scopes. I decided to spend the entire night viewing objects using 2" TeleVue Nagler 20mm Type 5's in the Siebert Elite 45's in the 2x mode which produced about 300x mag.

My first object was of course Saturn and the seeing at times showed the planet's exquisite views with granularity readily apparent in the Crepe Ring. The colors on part of the planet were clearly olivine and the detail was simply tack sharp at times.

Pieces of clouds moved in and out for several hours so I took a break and when the Sagittarius star cloud was due South, I began picking off objects with the binoviewers and the large scope. First object was M17 (Swan Nebula) without an OIII filter. The Swan's main body filled up most of the view and was quite pronounced. I then decided to go to M20 (Trifid Nebula) again without a filter, the view at 300x almost stopped my heart. The significant light throughput through the bins could only be described as "ethereal" and the dark lanes in the nebula in the shape of a propeller were extremely etched. It was a view I had never, ever had with two eyes.

Next was the globular cluster M4 and at 300x, the FOV was barely larger than the cluster and showed the most incredible three-dimensional views of a cluster that I had ever seen. It is very hard to describe the three-D illusion and how enhanced the views were with two eyes. I then went to M22 and the same experience only intensified by a factor of "x?" showed the barely framed globular in Sagittarius. From there, I proceed to view another significant cluster than night which was M13 in Hercules. Again, breathtaking 3-D views of the huge globular.

I needed some galaxy views so swung the telescope to M51 and for about 10 minutes, the clouds stayed out of the way and the two interacting galaxies were HUGE in the eyepiece and my large aperture scope and the 20mm Naglers allowed for extremely sharp views of the spiral arms and the bridge leading to the smaller of the two galaxies. I was really knackered from having worked part of the day and the drive and I called it a night.

Night two and my buddy Mike Harvey had just set up his 28" f/3.66 telescope and I had previously given him a brief taste of the Siebert's on another evening. On this night, he recommended that we use the 1.3x components of the 2" OCA and instead opt for very large fields of view with my 36mm 2" Siebert Observatory eyepieces that sport a 65 degree FOV and have 20mm of eye relief. IIRC, the first object after switching to the low-powered setup was M17 and Mike was very impressed with the light throughput and the images. M20 was like nothing he had ever seen while viewing it without a filter. We then went to M31, the Andromeda Galaxy and this is where it became unbelievably interesting. Mike is a very accomplished terrestrial photographer and so framed the galaxy such that the nucleus of M31 was in the very top part of the FOV and the two very prominent dust lanes were coming down and flowing with the companion galaxy of M32. The views again can only be described as "ethereal". We went to the Lagoon Nebula (M8) as I had done the night before and the views without a filter were terrific. One of the last objects we viewed on Friday night was the Double Cluster in Perseus. Because the 2" binoviewers had such a large FOV, we were able to frame the nucleus of each of the two clusters at both sides of the view.

There are a myriad of take away thoughts related to the use of these incredible BV's that are now optimized for fast Newts.
1. The new Siebert 2" OCA is very adept at taming coma in fast scopes.
2. The Siebert 2" 36mm Observatory ep's that weigh less than 9 ounces each with 65 degree FOV and 20mm of eye relief were the MOST comfortable binocular views that Mike and I had ever had with any less than dedicated high-end large astro binoculars. Mike commented that the Siebert 45's allowed for binocular views that could not be had in even the highest dollar APO bins because they were not backstopped by uber-large aperture that we could get with our telescopes.
3. The views with the Siebert 36mm's were so comfortable that there was simply no eyestrain or even sense that you had to accommodate views through two large eyelenses and all you had to do was have your eyes open and the views presented themselves with no sense of having work like is sometimes the case with 1.25" ep's.
4. Harry Siebert will be sending me an adapter ring to accommodate 2" filters and all of the nebulae and many more will be re-visited with passband properties to tease out even more of the nebulosity.

Harry Siebert advised me that due to the longstanding demand for these binoviewers that are essentially more rare than most limited-run scopes like an AP f/5 Stowaway, he is going to be concentrating his efforts on building these Elite 45's and his 3", 4" and even 5" observatory eyepieces that he has been supplying to large professional observatories.

These hand-made bins are expensive but surprisingly light weight and with the light Siebert ep's, are essentially not much heavier if any than my Baader Mark V's with 24mm Pans. To say that I am impressed would be a significant understatement. Although there is some slight loss of light and possibly a tad of detail compared to monocular viewing, the views are so comfortable that I will likely be most often sidelining my complete set of Ethos ep's in these large Newtonians. I also have more work to do in terms of putting these to use in my 20" f/3 JP Astrocraft and seeing how spectacular the FOV is with this smaller and even faster Newtonian.

#2 havasman

havasman

    Messenger

  • -----
  • Posts: 471
  • Joined: 04 Aug 2013
  • Loc: Dallas, Texas

Posted 27 July 2014 - 07:48 PM

Wow!
Thanks for sharing that exeprience.

#3 Bob S.

Bob S.

    Surveyor 1

  • *****
  • Posts: 1835
  • Joined: 14 Jul 2005

Posted 28 July 2014 - 11:44 AM

I just found out that Siebert Optics makes 2" 24mm 3-element ep's that are reportedly pinpoint to the edge with the new 2" OCA. I ordered a pair today and can't wait to use these light 5 ounce ep's with the Elite 45's. With the 36mm OBS ep's, that might make my 20mm Naglers a bit redundant? Only time will tell.

#4 gatorengineer

gatorengineer

    Mercury-Atlas

  • *****
  • Posts: 2530
  • Joined: 28 Feb 2005
  • Loc: Hellertown, PA

Posted 28 July 2014 - 02:43 PM

I also have the Blacknight 45's.... Mine are mirrors not prisms, hence the light weight. I would strongly recommend a pair of 17 ethos..... I don't as of yet have the new larger OCA and am waiting on hearing back from Harry about getting the 0 mag version...

#5 Bob S.

Bob S.

    Surveyor 1

  • *****
  • Posts: 1835
  • Joined: 14 Jul 2005

Posted 28 July 2014 - 03:12 PM

Mark,

Thanks for the correction. Harry advised that he uses a cube beam splitter onto three 1/10th wave mirror surfaces to move the light. The advantages are that the BV is .5-1 pound lighter than if he used prisms exclusively. I changed my original post to reflect the correct information. Thanks again for alerting me to how Harry was able to make them so light. They fare very well against my Baader Mark V's and I like the performance of the Siebert's better than the Baaders which is saying quite a bit because both are great BV's.

#6 gatorengineer

gatorengineer

    Mercury-Atlas

  • *****
  • Posts: 2530
  • Joined: 28 Feb 2005
  • Loc: Hellertown, PA

Posted 29 July 2014 - 07:58 PM

I ordered the new OCA cant wait to get it.... Thanks

#7 Bob S.

Bob S.

    Surveyor 1

  • *****
  • Posts: 1835
  • Joined: 14 Jul 2005

Posted 05 August 2014 - 01:14 AM

I also have the Blacknight 45's.... Mine are mirrors not prisms, hence the light weight. I would strongly recommend a pair of 17 ethos..... I don't as of yet have the new larger OCA and am waiting on hearing back from Harry about getting the 0 mag version...

Gatorengineer,

 

I talked with Harry Siebert today and he said that his new 2" OCA at 1.3x is about the best he can do for Newtonians. He said that it might be possible to do a 1.0 but it would likely only work in refractors and SCT's. It appears that your hopes for anything less than 1.3x is not on the horizon. He said that the images would not be crisp at that low a magnification on his current Elite 45's.



#8 gatorengineer

gatorengineer

    Mercury-Atlas

  • *****
  • Posts: 2530
  • Joined: 28 Feb 2005
  • Loc: Hellertown, PA

Posted 06 August 2014 - 12:04 PM

I ordered a 3 inch newt focuser from moonlight to be better able to handle the payload...

#9 Bob S.

Bob S.

    Surveyor 1

  • *****
  • Posts: 1835
  • Joined: 14 Jul 2005

Posted 06 August 2014 - 05:32 PM

I ordered a 3 inch newt focuser from moonlight to be better able to handle the payload...

I see that they list a 2.5" large Newtonian focuser. Is a 3" a new option that they do not have listed on the Moonlite website?



#10 gatorengineer

gatorengineer

    Mercury-Atlas

  • *****
  • Posts: 2530
  • Joined: 28 Feb 2005
  • Loc: Hellertown, PA

Posted 09 August 2014 - 05:45 PM

mine I believe is serial number 1....  not on the website yet, supposed to ship next week.



#11 Bob S.

Bob S.

    Surveyor 1

  • *****
  • Posts: 1835
  • Joined: 14 Jul 2005

Posted 30 August 2014 - 08:12 AM

Well, I just received a pair of Siebert 24mm 2" Observatory ep's and a 2" adapter ring to be able to mount 2" filters at the end of the new 1.3/2.0x 2" Newtonian OCA. The early morning views of M42, M31 and the Little Dumbell were beautiful with this new rig and my Siebert 45 Elites. It is doubtful that I will sell my pair of 20mm Nagler T5's but I like the reduced magnification. The FOV is smaller in the Siebert's than the Naglers so I am not sure how much of a difference the AFOV will be? I do know that I liked the 36mm Siebert Observatory ep's so much that I wanted to try another pair of his 2" creations.

 

Having the ability to place a filter on these exquisite binoviewers was a must and Harry will be offering the CNC machined adapter part for others interested in it who have the Elite 45's. I told Harry that looking at such majestic objects as the Swan, Eagle, Trifid, etc. with binoviewers in my 20" and 32" scopes was a must with filtration to get the most out of the two-eyed views. I am quite a happy camper at this moment and can't wait for more clear skies to use these terrific bins and my three sets of ep's. Bob


  • havasman likes this






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics