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

Ed Ting's Orion 120 Review

  • Please log in to reply
174 replies to this topic

#151 LDW47

LDW47

    Aurora

  • *****
  • Posts: 4,641
  • Joined: 04 Mar 2012
  • Loc: North Bay,Ontario,Canada

Posted 18 September 2020 - 10:00 PM

I’ve always enjoyed Ed’s reviews.  He is very knowledgeable and his enthusiasm is obvious.  I’ve always liked how he endeavors to cover a wide range of gear, from Taks and AP’s on one end and scopes like the ST120 on the other.  He ably explains just how one AP might slightly best a Tak performance-wise in a shootout, but at the same time he conveys how both are still a joy to look through.  By similar token, he points out the shortcomings of the ST 120 while at the same time makes a convincing case that it’s still great fun to use and gives a big bang for the buck.  I hope he’ll keep them coming for a long time.

Its the way it should be.



#152 Jeff B

Jeff B

    Fly Me to the Moon

  • *****
  • Posts: 7,042
  • Joined: 30 Dec 2006

Posted 18 September 2020 - 10:04 PM

It's under "My Settings" in your member account settings.

 

 

attachicon.gifdisplay-1.jpg

 

attachicon.gifdisplay-2.jpg

 

 

Bob F. 

Thanks Bob, I see it now.  Mine is set for the forum default setting.

 

So it's six pages.



#153 Jeff B

Jeff B

    Fly Me to the Moon

  • *****
  • Posts: 7,042
  • Joined: 30 Dec 2006

Posted 18 September 2020 - 10:27 PM

Ok, I just ordered one with a set of rings.

 

When I get it, I'll set it up in DPAC and publish the results.

 

Jeff


  • tony_spina, turtle86, BFaucett and 1 other like this

#154 Mitrovarr

Mitrovarr

    Gemini

  • -----
  • Posts: 3,047
  • Joined: 12 Sep 2004
  • Loc: Boise, Idaho

Posted 19 September 2020 - 02:32 AM

Cool, I can't wait to see the DPAC results.

My guess judging from mine is that the optics will be decent enough except for the inherent issues of chromatic and spherical aberration and maybe some miscollimation from focuser slop.

#155 Thomas Marshall

Thomas Marshall

    Viking 1

  • *****
  • Posts: 674
  • Joined: 24 Feb 2015
  • Loc: Spring Valley AZ.

Posted 19 September 2020 - 04:08 AM

Review? - Demonstration?   6 pages? - 2 pages? Either/either, neither/neither, - tomato/tomahto, - potato/potahto.  I like Ed Tings astro-videos. He knows a lot, and shares it well. 


  • turtle86 likes this

#156 Jeff B

Jeff B

    Fly Me to the Moon

  • *****
  • Posts: 7,042
  • Joined: 30 Dec 2006

Posted 19 September 2020 - 07:41 AM

I'm really curious too.  It's certainly cheap enough and I've found some Orion low budget surprises (80ED, 100ED and 110ED) of excellent optical and very good mechanical quality.  Ditto the SW120ED

 

When I get it, I'll do what I normally do and check the focuser alignment with my laser and then the lens with a Cheshire.  That gives me a really good baseline.  I'll also evaluate it visually on its own, not in comparison, then the DPAC tests and an indoor star test.  

 

If it's a stinker, it will go back.   But we'll see in a couple of weeks.

 

This stuff is fun for me...but I'm odd any way...and I dress funny too.

 

Jeff


  • 3 i Guy likes this

#157 LDW47

LDW47

    Aurora

  • *****
  • Posts: 4,641
  • Joined: 04 Mar 2012
  • Loc: North Bay,Ontario,Canada

Posted 19 September 2020 - 08:41 AM

Review? - Demonstration?   6 pages? - 2 pages? Either/either, neither/neither, - tomato/tomahto, - potato/potahto.  I like Ed Tings astro-videos. He knows a lot, and shares it well. 

And those vids don’t have page numbers, lol !


  • Thomas Marshall likes this

#158 LDW47

LDW47

    Aurora

  • *****
  • Posts: 4,641
  • Joined: 04 Mar 2012
  • Loc: North Bay,Ontario,Canada

Posted 19 September 2020 - 08:43 AM

I'm really curious too.  It's certainly cheap enough and I've found some Orion low budget surprises (80ED, 100ED and 110ED) of excellent optical and very good mechanical quality.  Ditto the SW120ED

 

When I get it, I'll do what I normally do and check the focuser alignment with my laser and then the lens with a Cheshire.  That gives me a really good baseline.  I'll also evaluate it visually on its own, not in comparison, then the DPAC tests and an indoor star test.  

 

If it's a stinker, it will go back.   But we'll see in a couple of weeks.

 

This stuff is fun for me...but I'm odd any way...and I dress funny too.

 

Jeff

I would hate to see your routine for a $500-$600 scope, lol !



#159 t.r.

t.r.

    Fly Me to the Moon

  • ****-
  • Posts: 6,179
  • Joined: 14 Feb 2008
  • Loc: 1123,6536,5321

Posted 20 September 2020 - 05:16 PM

Don’t look now but Ed Ting just uploaded an ST 80 YouTube video. Let’s do this all over again!

Edited by t.r., 20 September 2020 - 05:17 PM.

  • Sarkikos, LDW47, BFaucett and 1 other like this

#160 kksmith

kksmith

    Viking 1

  • -----
  • Posts: 564
  • Joined: 08 Mar 2018
  • Loc: Montana

Posted 20 September 2020 - 05:32 PM

Perhaps Ed may have read this thread and he’s tweeting noses.
  • BFaucett likes this

#161 Echolight

Echolight

    Viking 1

  • -----
  • Posts: 908
  • Joined: 01 May 2020
  • Loc: Texas

Posted 20 September 2020 - 07:47 PM

Don’t look now but Ed Ting just uploaded an ST 80 YouTube video. Let’s do this all over again!

Wut? No link?



#162 Thomas Marshall

Thomas Marshall

    Viking 1

  • *****
  • Posts: 674
  • Joined: 24 Feb 2015
  • Loc: Spring Valley AZ.

Posted 20 September 2020 - 08:02 PM

Yeah, - and I liked it also, - but like a TV episode that you invest your time in, it ends with "Too be continued", - it's just part 1. I hate getting caught in those "Too be cont." deals. 


  • turtle86 and Echolight like this

#163 BFaucett

BFaucett

    Surveyor 1

  • *****
  • Posts: 1,802
  • Joined: 12 Jul 2014
  • Loc: Houston, Texas 29.779 -95.603 (approx)

Posted 20 September 2020 - 10:22 PM

Wut? No link?

 

https://www.youtube...._channel=EdTing

 

Bob F.


  • Echolight likes this

#164 peleuba

peleuba

    Vanguard

  • *****
  • Posts: 2,478
  • Joined: 01 Dec 2004
  • Loc: North of Baltimore, MD

Posted 21 September 2020 - 09:31 AM

When I get it, I'll set it up in DPAC and publish the results.

 

 

I've got one in the queue as well.  Will be a few months as I have some other scopes in front of it that I need to complete in 2020.

 

To me, the argument that was made earlier in the thread stating there is no point in testing because they are cheap, fast, widefield achromats is not germane.    Purchase price and design should not be used as guides for testing.  There have been some very good telescopes that have looked middling on paper but test out fantastically.  The ED80 comes to mind - I've never seen a bad one.

 

Testing telescopes and optical systems (and publishing the results) helps everyone understand aberrations and their impact on the view (or photograph).  Price point and design should not be the determiner.  Every serious review should include some test data.  Just think how much better the the reviews in S/T and Astronomy would be.

 

The oft-written ubiquitous line that many, many reviews contain:  "...the star test pattern inside and outside of focus was textbook..."  is a joke.  Anyone who has tested an achromat or sub F/9 ED doublets knows this is not the case.



#165 RLK1

RLK1

    Viking 1

  • -----
  • topic starter
  • Posts: 501
  • Joined: 19 Apr 2020

Posted 21 September 2020 - 02:11 PM

Let's hope those testers get those green filters out for their tests, too. Reminds of me of the following discussion between a poster on the AM forum and Roland:

"where a poster states this:"have an older FPL53 Triplet that when star testing shows almost two different test depending on which filter I use. With the yellow filter the star test is funtionally perfect. Nice symetry, equal intensity of rings on both sides of focus. With the green filter the rings are asymetrical and don't look good at all. I heard that achros shoud be tested with green filters and FPL53 should be tested with yellow filters. Is this accurate or is my lens flawed?? Thanks" To which Roland Christen responds: "Your lens is probably fine. I would not expect the Fresnel rings to show symmetry in anything faster than F12 in an apo lens for the various colors. It's much more important for your lens to show round extra-focal star images than symmetry in and out of focus."

Obviously the optical testing is going to be very critical since everybody is going to recognize  the difference between a 1/4 and a 1/2 wave in a 120mm f5 richfield refractor anyway...



#166 REC

REC

    Voyager 1

  • *****
  • Posts: 11,856
  • Joined: 20 Oct 2010
  • Loc: NC

Posted 21 September 2020 - 03:44 PM

Cool review:

https://www.youtube....h?v=Y8OedyDOYwo

Wish he would have added a filter or two and discussed them for visual and imaging...

WOW, what a great find! I had read some of his articles and reviews over 10 years ago and none in a long time. It's nice to put a face to him and what an interesting fellow. I going to watch some more of his videos as he does a wonderful job on camera. Thanks for the link!


  • Thomas Marshall likes this

#167 REC

REC

    Voyager 1

  • *****
  • Posts: 11,856
  • Joined: 20 Oct 2010
  • Loc: NC

Posted 21 September 2020 - 03:47 PM

I tried on my Bresser AR102 / 1000 achromat with a Celestron neutral variable polarizing filter, finally using only one of the two filters on Jupiter ...
... surprising result , disappearance of the little CA present without the filter (F / 10), in particular in the blue while preserving the details and the contrast.
With just one of the two filters, little light is lost, which on Jupiter is uncomfortable.
Sometimes the tests bring good surprises.

I also have the C102 and it has very little CA and I get rid of some of it with a Baader fringe killer. I only paid $60 for just the tube and put it on a nice AZ mount and it's become my most used scope!



#168 peleuba

peleuba

    Vanguard

  • *****
  • Posts: 2,478
  • Joined: 01 Dec 2004
  • Loc: North of Baltimore, MD

Posted Yesterday, 09:24 AM

Let's hope those testers get those green filters out for their tests, too. 

 

Yes, as I said in a PM, I'm familiar with that discussion on AM...     Perhaps I am stating the obvious, but typically, double pass auto collimation (DPAC) and interferometry don't require any sort of interference filter to isolate a specific color.  The star test of an achromat is the exception and to do properly requires Wratten #11 yellow-green, Wratten # 56 light green and Wratten # 58 green in a stacked and single configurations.

 

If the scope is as good as Ed Ting, you and others say, I think we all may be pleasantly surprised at how well it tests at the wavelength in which it was designed.

 

This has been an informative thread, thank you for starting it.


Edited by peleuba, Yesterday, 09:33 AM.


#169 RLK1

RLK1

    Viking 1

  • -----
  • topic starter
  • Posts: 501
  • Joined: 19 Apr 2020

Posted Yesterday, 10:15 AM

Yes, as I said in a PM, I'm familiar with that discussion on AM...     Perhaps I am stating the obvious, but typically, double pass auto collimation (DPAC) and interferometry don't require any sort of interference filter to isolate a specific color.  The star test of an achromat is the exception and to do properly requires Wratten #11 yellow-green, Wratten # 56 light green and Wratten # 58 green in a stacked and single configurations.

 

If the scope is as good as Ed Ting, you and others say, I think we all may be pleasantly surprised at how well it tests at the wavelength in which it was designed.

 

This has been an informative thread, thank you for starting it.

On the contrary, I'd expect the opposite but I wouldn't limit myself to an optical evaluation. I'd evaluate the mechanical functions first, specific to the collimation of the elements within the tube, meaning the alignment of the fixed cell, focuser induced collimation errors, stray light suppression by baffling and an evaluation under load, ie with focuser induced errors associated with heavy eyepieces or cameras. While I'd expect the collimation issues to be obvious under the optical testing as well, I'd prefer to have a more thorough optical mechanical assessment first.  

I'd agree that we'd all be pleasantly surprised if the objective performs well under testing but that's not what I'm expecting. I do expect to have a thorough report detailing various defects evident during testing. I think that's axiomatic and I expect it to conform to the expectations of the tester.

That said, I'm not particularly concerned about a sample size of one so whatever the findings may be, I'd be skeptical that they can be generalized to an entire production line of mass produced telescopes.

Further, as I've previously stated, I doubt most observers can discern the difference between a 1/4 wave and 1/3 or so in the 120mm F5 richfield unit and I'd bear in mind at all times that the operating parameters for which the scope is designed and marketed by the seller should be prioritized above that realized in an optical bench test...


  • LDW47 likes this

#170 LDW47

LDW47

    Aurora

  • *****
  • Posts: 4,641
  • Joined: 04 Mar 2012
  • Loc: North Bay,Ontario,Canada

Posted Yesterday, 10:38 AM

The great Ed Ting if he reads some of this, which I hope he doesn’t ( he's too smart for that ), will be shaking in his shoes about what some ( perfectionists ? ) would have liked or demanded he do for a $250 scope that many great fellow astronomers are already very familiar with its capabilities, its virtues ! Up to now, I am sure, he was just happy to add his 2 cents, his experience to the scopes assets and capabilities ? Does any one think ?   Vive la’  Ed Ting !


Edited by LDW47, Yesterday, 10:40 AM.


#171 t.r.

t.r.

    Fly Me to the Moon

  • ****-
  • Posts: 6,179
  • Joined: 14 Feb 2008
  • Loc: 1123,6536,5321

Posted Yesterday, 11:16 AM

Further, as I've previously stated, I doubt most observers can discern the difference between a 1/4 wave and 1/3 or so in the 120mm F5 richfield unit and I'd bear in mind at all times that the operating parameters for which the scope is designed and marketed by the seller should be prioritized above that realized in an optical bench test...


I disagree. Distinguishing between 1/4 wave and 1/3 wave is easy by eye...harder is 1/6 versus 1/4 and difficult would be 1/8 to 1/6 wave.

#172 RLK1

RLK1

    Viking 1

  • -----
  • topic starter
  • Posts: 501
  • Joined: 19 Apr 2020

Posted Yesterday, 11:36 AM

I disagree. Distinguishing between 1/4 wave and 1/3 wave is easy by eye...harder is 1/6 versus 1/4 and difficult would be 1/8 to 1/6 wave.

By all means feel free to disagree that you can easily discern the difference between 1/4 wave and 1/3 wave in a rich field 120mm f5. Reminds me of a post from an optician who noted most SCs test out at around 1/3 wave and their owners are perfectly happy with them...



#173 Mitrovarr

Mitrovarr

    Gemini

  • -----
  • Posts: 3,047
  • Joined: 12 Sep 2004
  • Loc: Boise, Idaho

Posted Yesterday, 12:06 PM

Yeah, I've heard that a legitimate 1/4 wave telescope is actually pretty good. People got jaded by exaggerated claims by manufacturers.
  • peleuba and RLK1 like this

#174 peleuba

peleuba

    Vanguard

  • *****
  • Posts: 2,478
  • Joined: 01 Dec 2004
  • Loc: North of Baltimore, MD

Posted Yesterday, 02:21 PM

The great Ed Ting if he reads some of this, which I hope he doesn’t ( he's too smart for that ), 

 

But you've read this, so what does that say?

 

I am only pointing this out to highlight the ludicrousness of this part of your post...   You've also insulted the intelligence of everyone here who has either:  (1) made a contribution to the thread and/or (2) read the thread.

 

Perfection is not the issue.  In fact, perfection is often the enemy of good.   (let that sink in for a moment)

 

In any event, respectfully, maybe just sit back and enjoy the widefield views this scope can provide and take a minute for the brain to catch up with your typing fingers.    


Edited by peleuba, Yesterday, 02:26 PM.


#175 peleuba

peleuba

    Vanguard

  • *****
  • Posts: 2,478
  • Joined: 01 Dec 2004
  • Loc: North of Baltimore, MD

Posted Yesterday, 02:29 PM

Yeah, I've heard that a legitimate 1/4 wave telescope is actually pretty good. People got jaded by exaggerated claims by manufacturers.

 

An honest ¼ wave telescope with pure spherical being the only aberration would make a lot of people happy.  Including me.   

 

In the real world, when someone refers to a star test that is a ¼ wave under/overcorrected they are referring to spherical aberration.  But its never the only aberration and is accompanied by zonal errors, coma, astig etc...  These aberrations are additive.  So a telescope that exhibits ¼ wave of spherical error will often be much worse and not diffraction limited.


Edited by peleuba, Yesterday, 02:30 PM.

  • Jeff B likes this


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