Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

TMB Monocentrics?

  • Please log in to reply
12 replies to this topic

#1 agmoonsolns

agmoonsolns

    Mariner 2

  • *****
  • topic starter
  • Posts: 287
  • Joined: 17 Sep 2018
  • Loc: Puget Sound

Posted 06 December 2018 - 09:17 PM

Are the TMB Monocentrics worth the high cost? What's it like observing with them and how do they compare with other high end planetary eyepieces like the Zeiss, Vixen HR, Pentax, etc.?



#2 Aleko

Aleko

    Viking 1

  • *****
  • Posts: 999
  • Joined: 01 Aug 2010
  • Loc: Georgia

Posted 06 December 2018 - 10:32 PM

I find them to be on par with the ZAO-IIs, and use them, with XOs, to fill in the gaps of my Zeiss set. High contrast, low scatter. Not the most comfortable eyepieces though. Like the Zeiss, I use them on the very best of nights when they will make a difference. Under just normal seeing conditions, the Pentax XWs are my planetary eyepiece choice.  (I find nothing special about the HR.)

 

My 2 cents of what will probably be many dollars worth of opinions!

 

Alex


Edited by Aleko, 06 December 2018 - 10:34 PM.


#3 Jeff Morgan

Jeff Morgan

    Cosmos

  • *****
  • Posts: 9996
  • Joined: 28 Sep 2003
  • Loc: Prescott, AZ

Posted 06 December 2018 - 11:14 PM

Worth is always a personal thing ... 

 

I have never tried the famous Zeiss Abbe Orthos, but I will accept they judgement of the Planetary Experts they are #1. 

 

Of the ones I have tried, performance-wise TMB SMC's were the best performers. They edge out UO HD Orthos, Brandons, Astro-Physics SPL's, and the 5.1 Pentax XO. And out distanced my Delos and Pentax XW. And even the Leica too.

 

I owned sets of Brandons, SPL's, and TMB's concurrently so I did lots of comparisons. When I thought I saw something (such as a Jovian feature or faint double star buried in a diffraction ring), the TMB would be the eyepiece that could confirm it. I never recall that relationship working in reverse.

 

Out of fairness, one needs better than average seeing to really separate the pack. Pickering 5 or less will frustrate the effort.

 

SMC's have tight eye relief, but better than the aforementioned simple designs excepting the SPL's, which were actually pretty good for simple eyepieces (the SPL's were really a great optical/mechanical concept). And of course better than Plossls, which have about the worst eye relief but somehow always seem to get a pass on that.

 

Getting back to worth ... if I lived in the Florida Keys, I would buy SMC's again. Otherwise, for I will probably keep my Leica, or possibly re-buy the Brandons. When you buy the set, Brandons are reasonable on the cost/performance ratio. As singles, they are pricey.

 

One eyepiece I have not tried and very curious about - the Takahashi Orthos.


  • steve t likes this

#4 bobito

bobito

    Apollo

  • *****
  • Posts: 1252
  • Joined: 15 Aug 2014
  • Loc: Litchfield County, CT

Posted 07 December 2018 - 12:53 AM

I'll echo the posts above.  I prefer the SMC over the AP SPL, which is the only high end planetary EP on this level I have compared it to.  A big difference between the SMC and Ap SPL is that the SMC Barlow very well, the SPL gets soft on the edges when barlowed.  This helps with the cost as I can have 3 for the price of one when used with my 2x an 3x TV barlows.



#5 Starlease

Starlease

    Explorer 1

  • -----
  • Posts: 92
  • Joined: 11 Aug 2018
  • Loc: Rocky mountains.

Posted 07 December 2018 - 04:18 AM

I have owned them all over the years and the TMB monos and super monos are among the best if you can put up with the 30 degree field of view. Brand new today and just as good are the Takahashi TOEs with 52 degree field with some eye relief unlike the monos with none. Forget the Abbe orthos they are a completely lower tier eyepiece range.

 

Still have some Claves which are great in f10 and longer scopes. 60 degree fields. Again zero eye relief.


Edited by Starlease, 07 December 2018 - 04:44 AM.


#6 Allan Wade

Allan Wade

    Gemini

  • *****
  • Posts: 3356
  • Joined: 27 Jan 2013
  • Loc: Newcastle, Australia

Posted Yesterday, 01:14 AM

I put together some TMB SMC's and evaluated them for almost 2 years. My plan was to build a complete set with pairs in the longer focal lengths. In my case, I was looking to build a minimum glass set for planetary viewing and threshold deep sky type observing. I really liked the eyepieces and saw for myself that they deserved their high performance reputation.

 

But, having spent a lot of time comparing them, I became familiar with some of their limitations. They specifically don't perform so well in fast telescopes, which I typically have. The correction at the edges is poor, which leads to the next issue. A 30 degree field of view is ok, but does become annoying eventually. So when perhaps only 70% of that field is usable, it results in a very tiny field to observe the object. Ok for planets, not for deep sky.

 

Another thing I observed over and over was that the SMC's did not perform as well as the ZAO's or Tak Abbes on revealing threshold deep sky objects. This is completely contra to what I was expecting given the SMC design, but I can only put it down to coatings.

 

I remember observing Deimos one night and seeing it clearly using the ZAO's and Tak Abbes. Switched to the Delos and it was invisible, even though I knew exactly where it was, the little moon couldn't punch through all the scatter. Then switched to the SMC and Deimos re-appeared but with less certainty than with the Abbe's. I switched back and forth through the eyepieces and the performance remained constant. After almost 2 years, I kind of lost any remaining love for my SMC's after that night and sold them off.

 

I have 17 ZAO II's and Tak Abbes now that make up my complete minimum glass collection with bino pairs. They work beautifully in every scope I have including the f/3.3.


  • Paul G and Astrojensen like this

#7 agmoonsolns

agmoonsolns

    Mariner 2

  • *****
  • topic starter
  • Posts: 287
  • Joined: 17 Sep 2018
  • Loc: Puget Sound

Posted Yesterday, 01:29 AM

This is really terrific information, thank you everyone! How do the ZAOs, Takahashi Abbe orthos, and the Pentax compare? I am trying to put together a group of eyepieces for high power work and would like to choose right the first time.

 

Allan, just out of curiosity, what aperture and magnification were you using to see Deimos?



#8 Allan Wade

Allan Wade

    Gemini

  • *****
  • Posts: 3356
  • Joined: 27 Jan 2013
  • Loc: Newcastle, Australia

Posted Yesterday, 02:02 AM

The first time I saw Deimos was in my 12" dob at 280X. My bent is toward deep sky observing primarily with these min glass eyepieces, but also a fair bit of planetary in the binoviewer. I'm a huge fan of the Tak Abbes for the type of observing I do in my telescopes. On deep sky in particular I rate them alongside the ZAO's. All the threshold objects I go for in the 32" I use the Abbes to confirm them. In the big scope there's a significant gap in performance between the ZAO's and Tak Abbes and my Delos and Ethos.

 

Some random pics.

 

1.jpg

 

2.jpg

 

3.jpg

 

4.jpg


  • Astrojensen, eros312, Paul Morow and 2 others like this

#9 agmoonsolns

agmoonsolns

    Mariner 2

  • *****
  • topic starter
  • Posts: 287
  • Joined: 17 Sep 2018
  • Loc: Puget Sound

Posted Yesterday, 02:06 AM

Wow, what a breathtaking collection of eyepieces!



#10 Chris Lord

Chris Lord

    Vostok 1

  • *****
  • Posts: 144
  • Joined: 26 Sep 2004
  • Loc: Cambridge UK

Posted Yesterday, 04:25 AM

I use a TEC140EDAPO F/7 and have a set of TMB Mono's in theTEC eyepiece turret. They're not quite parfocal. 

 

I rate them highly. I've ray-traced them and compared the apo-objective+Mono+eye system aberrations to Zeiss Abbé system aberrations. The net results are similar but the TMB Mono's have the edge.

 

It depends of course on what you're observing. I'm a hi-res observer, planets, double stars, especially very unequal doubles and tight doubles. I enjoy pushing whatever 'scope I'm using to the seeing limit so the narrow AFoV and short eye relief doesn't bother me. I find it an advantage because there are no other distracting objects in the FoV and the eyepiece is worn almost like a monocle so no oblique stray light can shine between your Cornea and the eyelens.

 

But imo they're unnecessarily expensive. The profit margin must be many times the production and retail cost. In other words they've been marketed as prestige goods. And in that respect the ideal acruitement to a Standard Questar .

 

Chris Lord


  • payner, eros312 and SandyHouTex like this

#11 Astrojensen

Astrojensen

    Voyager 1

  • *****
  • Posts: 10955
  • Joined: 05 Oct 2008
  • Loc: Bornholm, Denmark

Posted Yesterday, 05:48 AM

But imo they're unnecessarily expensive. The profit margin must be many times the production and retail cost. In other words they've been marketed as prestige goods. 

I'm not so sure about that. The production runs were extremely small, compared to so many other eyepieces. This will of course drive the prices up. 

 

I never found myself in a position where I could actually afford them, so I've never tried them myself. I've experimented with Dollonds instead and they seem to offer most of the same advantages, such as extremely minimal scatter, etc., but are of course far less expensive and with an even narrower field of view.

 

 

Clear skies!
Thomas, Denmark



#12 Kent10

Kent10

    Skylab

  • *****
  • Posts: 4110
  • Joined: 08 May 2012

Posted Yesterday, 04:10 PM

I use a TEC140EDAPO F/7 and have a set of TMB Mono's in theTEC eyepiece turret. They're not quite parfocal. 

 

I rate them highly. I've ray-traced them and compared the apo-objective+Mono+eye system aberrations to Zeiss Abbé system aberrations. The net results are similar but the TMB Mono's have the edge.

 

It depends of course on what you're observing. I'm a hi-res observer, planets, double stars, especially very unequal doubles and tight doubles. I enjoy pushing whatever 'scope I'm using to the seeing limit so the narrow AFoV and short eye relief doesn't bother me. I find it an advantage because there are no other distracting objects in the FoV and the eyepiece is worn almost like a monocle so no oblique stray light can shine between your Cornea and the eyelens.

 

But imo they're unnecessarily expensive. The profit margin must be many times the production and retail cost. In other words they've been marketed as prestige goods. And in that respect the ideal acruitement to a Standard Questar .

 

Chris Lord

Chris, thanks for this.  Have you found anything equal or better than the TMB Mono's in your tests?



#13 payner

payner

    Apollo

  • *****
  • Posts: 1479
  • Joined: 22 Mar 2007
  • Loc: Bluegrass Region, Kentucky

Posted Yesterday, 05:53 PM

While I have no bench/quantitative tests for the set of Super Monocentric eyepieces, my trials with similalr four lens eyepieces mentioned (but not tried the Takahashi Abbe Orthoscopic line), the Super Monocentric eyepieces are the best to my eyes for the.objects generally observed. My primary targets are planets, multiple stars, planetary nebulae and globular clusters. 

 

I appreciate the cool (cold) rendering, excellent (lack) scatter control, and the presentation of low contrast features. For a useful set of planetary eyepieces, the many focal lengths in 1-mm increments is most helpful when teasing the most details for any given seeing condition. I did have the ZAO II set, they are excellent, but far too few focal lengths, and did not want to add the use of the Barlow.

 

Randy




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics