Jump to content


Photo

GSO Plossl vs Orion Plossl

  • Please log in to reply
25 replies to this topic

#1 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 14 April 2010 - 11:01 PM


GSO Plossl versus Orion Sirius Plossl: how do they compare?

GSO Plossls are fully multi-coated, Sirius plossls are only multi-coated. GSOs are about 30% cheaper, and just might be a better EP. Orion used to supply a lot of GSO products relabeled with the Orion name. Now Orion uses mostly Synta products for their Orion-labeled stuff. Some people have expressed that GSO is a step above Synta. Any thoughts? Any opinion about GSO plossls? Any opinions about GSO in general?

#2 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 16 April 2010 - 11:48 AM


No comparisons out there? Hmmm...

#3 Deep13

Deep13

    Mercury-Atlas

  • *****
  • Posts: 2773
  • Joined: 25 Jan 2005
  • Loc: NE Ohio

Posted 16 April 2010 - 12:07 PM

GSO = 6

Orion = half dozen

#4 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 16 April 2010 - 12:18 PM


So are you suggesting that Orion still uses relabeled GSO EPs for its Sirius/Highlight series? Or that they are both bargain bin Chinese Plossls (well, Taiwanese, technically speaking), so it doesn't matter?

With the possible exception of TeleVue Plossl, it seems that they might just all roll off the same assembly line somewhere in Asia and just have a different label slapped on them. It would be nice to know, however, what real differences exist and if the extra money spent on a "premium" plossl versus that spent on the bargain blowout series is money wasted or well-spent.

Any thoughts on GSO and cheap plossls in general is appreciated. Thanks! :grin:

#5 Kutno

Kutno

    Apollo

  • *****
  • Posts: 1133
  • Joined: 17 Aug 2009

Posted 16 April 2010 - 08:29 PM

Chuck,

The two Chinese Orion Sirius Plossls I have do not match up directly with my Taiwanese Celestron Omni - I believe, but have never absolutely verified, that the Omnis are made by GSO - Plossl focal lengths; however, I will give you a summary of comments concerning units in both lines with which I have had the most experience, to date, in a 6" F/8 Dob:

Sirius 10mm Plossl: On its own; perhaps, nothing to write home about - there is softness towards the edge - however, when matched with a 2x Orion Shorty Barlow, it has coughed up Ortho-like views of Jupiter; which, at times, have been better than those provided by a very good 5mm Ortho I have.

Sirius 25mm Plossl: Surprisingly, has matched the view I see in a 25mm Meade 3000 Plossl.

Omni 4mm Plossl: Has delivered very slightly brighter views than a very good 4mm Ortho I have; however, its sweet spot is too small for my tastes - there is softness not that far away from the central viewing area. That central spot is sharp, though; but not sharper than the Ortho. A relatively cheap tool for on-axis star testing.

Omni 6mm Plossl: Has a central sweet spot somewhat larger than the 4mm Omni; which delivers images that are generally sharper, on-axis, than two moderately priced, and different brand/manufacturer, 6mm "planetary-type" eyepieces in the stable. The latter two do perform better at the edge than the Omni, and have slightly wider fields of view.

Omni 15mm Plossl: A pair of these have performed very well, for me, in a binoviewer. I will even say that they performed excellently in the binoviewer, delivering images of Jupiter and the Moon that I will never forget. (Note: I am a newbie to binoviewing.)

Since you mentioned Tele Vue, I must confess that if I had to do it over again, I would have done less experimenting with the other brands, and would have spent the extra money for a complete set of Tele Vue Plossls. There is not one Tele Vue Plossl I have looked through which has disappointed me. Special mention must be given to their 7.4mm, 8mm, 20mm, 26mm and 32mm units.

#6 Deep13

Deep13

    Mercury-Atlas

  • *****
  • Posts: 2773
  • Joined: 25 Jan 2005
  • Loc: NE Ohio

Posted 17 April 2010 - 10:24 AM

With a 2x Celestron Ultima Barlow and a 5" f/12 refractor I found the 12.5mm UO ortho gave sharper views than the 17mm Sirius Pl. though the 17 had better glare control. The 15 TV Pl. was at least as sharp as the ortho, with better contrast and the best glare control of the three.

Frankly, there are no truly premium Pls. available new. I would consider TV to be the best of the widely available affordable units and Synta to be a "bargain" brand. All the really premium units are Abbe orthoscopic, monocentric or other proprietary design. And those are no longer in production.

#7 Mapleton

Mapleton

    Viking 1

  • -----
  • Posts: 525
  • Joined: 06 Dec 2009
  • Loc: United States

Posted 17 April 2010 - 10:54 AM

Since you mentioned Tele Vue, I must confess that if I had to do it over again, I would have done less experimenting with the other brands, and would have spent the extra money for a complete set of Tele Vue Plossls. There is not one Tele Vue Plossl I have looked through which has disappointed me. Special mention must be given to their 7.4mm, 8mm, 20mm, 26mm and 32mm units.


I agree with this. Often people are turned off by the price of TV, but you know what you're getting and you know you're going to like it.

It can often be more expensive to "experiment" with other brands, than it can be to just get the EPs you want.

#8 Hrundi

Hrundi

    Vanguard

  • -----
  • Posts: 2006
  • Joined: 06 Feb 2008
  • Loc: Estonia

Posted 17 April 2010 - 12:58 PM

Well there's a review by Chris Lord that suggests that at shorter focal lengths, it wouldn't matter if you go televue or GSO, but I understand that mentioning that review here can induce some excitement :gotpopcorn:

#9 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 17 April 2010 - 01:55 PM

I agree with this. Often people are turned off by the price of TV, but you know what you're getting and you know you're going to like it.

It can often be more expensive to "experiment" with other brands, than it can be to just get the EPs you want.


I can agree with this to an extent--especially for the TV Plossls, where the price is still relatively affordable. When it comes to some of the *really* expensive TV stuff (e.g. Nagler, Ethos, etc.), I am inclined to go for the "good enough" EP of another brand, rather than the top-o'-the-line and mucho expensive TV. I know that many disagree, and I can't argue at all with someone who really wants the best, but for me there is a certain price/performance tradeoff that will probably limit me to more modest EPs.

Actually this brings up a point: reviews for cheap to mid-range EPs are ultimately more useful and important. You don't need a review to tell you that an Ethos is awesome. You do need a review to tell you how much of a compromise you are making by using a GSO plossl or an Orion Expanse or a Baader Hyperion, each of which fills a certain need and fits a certain budget.

#10 great_bear

great_bear

    Viking 1

  • -----
  • Posts: 989
  • Joined: 05 Jul 2009
  • Loc: Walthamstow, London, UK

Posted 17 April 2010 - 06:27 PM

In my SW Mak 180 Pro, the 15mm GSO Plossl is noticeably *better* than the TV 15mm. The GSO is sharper and planetary detail is more evident. This wasn't the result I wanted because:

a) I had to pack up the TeleVue eyepiece, and send it back for refund.
b) I wanted to have a TV eyepiece in my collection - but now I can't justify it.

Of course, the GSO 15mm has a fuzzy field stop - which is annoying - but it always struck me as otherwise being a very sharp eyepiece.

At 12mm, (in the Mak) the GSO was at least the equal in sharpness and detail of the Baader Genuine Orthoscopic 12.5mm - however at 6mm the BGO is markedly superior than the GSO. I'm expecting the same to be true at 9mm but will confirm this as soon as I know for sure.

The 25mm GSO is an eyepiece I love - particularly on the moon, and also, my love for the 32mm GSO Projection Eyepiece is well-known :-)

Although I've never compared the 25mm and 32mm to other eyepieces, I don't need to. I love them as they are, and have no plans to change them for anything else.

In summary, if I had adopted the "buy all-Televue - it's worth it" philosophy, it would have been a total waste of my money. In my F15 SW Mak 180 Pro, the GSO Plossls are a match for anything else in focal lengths down to 10mm. Shorter than that, the quality of (e.g.) Baader Genuine Orthos really starts to shine.

Both the BGOs and TV eyepieces are better made than the GSOs in terms of baffling etc., in the longer lengths however, this didn't translate into views that were any better than the GSO.

#11 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 20 April 2010 - 03:13 PM


Wow, it's interesting to see such a positive review of the GSO. At most, I expected them to be an underpriced overachiever. I am pleasantly surprised to see that someone compares them favourably to the TV plossls.

#12 MikeRatcliff

MikeRatcliff

    Surveyor 1

  • *****
  • Posts: 1785
  • Joined: 12 Jun 2004
  • Loc: Redlands, CA

Posted 20 April 2010 - 04:53 PM

GSO versus Televue versus Brandon

Chris Lord also had good things to say about the GSO. Reading closely you can see he doesn't like Televue's marketing over the years.

Mike

#13 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 44011
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 20 April 2010 - 06:16 PM

I can agree with this to an extent--especially for the TV Plossls, where the price is still relatively affordable. When it comes to some of the *really* expensive TV stuff (e.g. Nagler, Ethos, etc.), I am inclined to go for the "good enough" EP of another brand, rather than the top-o'-the-line and mucho expensive TV. I know that many disagree, and I can't argue at all with someone who really wants the best, but for me there is a certain price/performance tradeoff that will probably limit me to more modest EPs.



One of the most important factors in choosing eyepieces is the focal ratio of the scope. I see you have two SCTs. At F/10, the performance of even simple widefield types like Erfles and Konigs is quite good, for such scopes, Naglers and Ethos's are probably over kill. One of the advantages of scopes like yours are that they are easier on eyepieces. If you were trying to buy eyepieces for an F/4 Newtonian, that pushes the equation towards those expensive TV eyepieces but fortunately you don't have that problem...

So,.. You mentioned the Orion Expanse.. These are Orion branded Synta Widefields. I have had a few of these, I had two of the 6mm, both the same, glare from outside the field of view. The 9 is quite wonderful, even in a fast scope. The 15mm and the 20mm should provide quite nice widefield views in your SCTs...

Jon

#14 Hrundi

Hrundi

    Vanguard

  • -----
  • Posts: 2006
  • Joined: 06 Feb 2008
  • Loc: Estonia

Posted 20 April 2010 - 07:48 PM

The chris lords review seems to suggest that even at F/4.7, it's not really clearly in favor (if in favor at all) of the TV's over GSOs.
From what I've gathered, it seems that the differences, if any, are going to be minor.

#15 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 44011
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 21 April 2010 - 05:11 AM

From what I've gathered, it seems that the differences, if any, are going to be minor.



In the April 1996 issue of Sky and Telescope, there is a nice report of some tests conducted on a variety of Plossls, it included the Meade 3000 and 4000 series, the Celestron Ultimas, the standard (Taiwanese) Celestrons, the Orion Sirius's, the TeleVues as well as a few others.

These tests included measurements on the optical bench and in the field, it is the most comprehensive review I have ever seen...

Their conclusion: All were reasonable eyepiece, the differences between the eyepieces were subtle, but in the end, the Ultimas and the TeleVues were observably better. For simple eyepieces like Plossls and Orthos that are essentially variations around a standand, this is almost always the case, there isn't a lot one can do to mess up the design, there is not a lot one can do to improve it. The Ultimas were 5 element but everything else was 4...

With widefield designs, there are major differences but with Plossls, even the inexpensive ones are quite decent.

Jon

#16 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11727
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 21 April 2010 - 08:36 AM

In my SW Mak 180 Pro, the 15mm GSO Plossl is noticeably *better* than the TV 15mm. The GSO is sharper and planetary detail is more evident. This wasn't the result I wanted...


Not an entirely unusual outcome as an eyepiece will perform diffierently in different scope designs, and the spot size it produces both on and off axis varies quite a bit depending on the focal ratio of the scope. In TV's case, we don't know the exact design so can't produce the exact spot behavior since it is proprietary. However, we do know that TV optimized them to work in faster scopes and to have an imporved off-axis (the reason stated in the patent and why they have the concave surface instead of the traditional plano surface of a symmetrical). So while one expects, and sees usually, that the TVs perform better off-axis in fast scopes than the other Plossls out there, once you put it in a longer focal ratio, it's less expensive competition can easily equal, and as people have commented, surpass it's performance. Would be interesting to see the spots based on the actual TV design to see how they behave at various focal ratios.

Of course, spots aren't everything as far as eyepiece performance is concerned...lens polish, coatings, and attention to baffling also play a major role in performance outcomes as these impact contrast in various ways, both good and bad.

#17 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11727
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 21 April 2010 - 08:42 AM

... reviews for cheap to mid-range EPs are ultimately more useful and important. You don't need a review to tell you that an Ethos is awesome. You do need a review to tell you how much of a compromise you are making by using a GSO plossl or an Orion Expanse or a Baader Hyperion, each of which fills a certain need and fits a certain budget.


OK...what would be the list of "budget" eyepieces you would consider best for such a review?? I'm not so sure I would mix price classes though -- in your example I would not consider a GSO Plossl and a Hyperion in the same league. However, things like GSO Plossl, Owl Enhanced Superwides, Owl Plossls, and maybe things available for a unit cost of say $35 or less might be an interesting thing :)

#18 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 21 April 2010 - 11:33 AM

OK...what would be the list of "budget" eyepieces you would consider best for such a review?? I'm not so sure I would mix price classes though -- in your example I would not consider a GSO Plossl and a Hyperion in the same league. However, things like GSO Plossl, Owl Enhanced Superwides, Owl Plossls, and maybe things available for a unit cost of say $35 or less might be an interesting thing



Sorry for any confusion--I wasn't trying to put Hyperion in the same league as the others. I said that the GSO plossl, the Orion Expanse, and the Baader Hyperion each fill a certain role at a certain budget within one's collection. I consider each of those three to be distinctly different EPs, which is why I chose them as examples. The only thing that they really have in common is that they each perform well above their respective costs--which was the point I was going for.

As for your idea for a comprehensive comparision--that would be great! If you choose price as the main selection criterion, then compare performance within a cost bracket regardless of design (which it seems like you are suggesting), that could be really interesting. It seems like most reviews are grouping EPs more by AFOV or design type as the primary criterion.

So what are all the EPs that are less than, say, around $75 new? Less than $35 new?

#19 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11727
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 21 April 2010 - 12:17 PM

So what brands are the real budget ones? Here's the list I have found. Any missing?

Owl - Black Night Super Plossl - 40/30/25/20/15/12.5/10/6.5/4 - $19-$23

Owl Enhanced Superwide - 20/15/9/6 - $34-$36

GSO Super Plossl - 40/32/25/20/15/12/9/6/4 - $30-$36

Sirius Plossl - 40/32/25/20/17/12.5/10/7.5/6.3 - $46-$52

GTO Plossl - 40/32/25/15/12/9/6/4 - $23-$40

Omni Plossl - 40/32/25/15/12.5/9/6/4 - $35

Meade 4000 Plossl - 40/32/26/20/17/12.4/9.7/6.4 - $39

AT High Grade Plossls - 20/17/12.5/6/4 - $25-$35

Sterling Plossl - 25/20/17/12.5/6/4 - $40-$50

AT Series 6 Economy Wide Field - 20/17/12/10 - $27

Vixen NPL Plossls - 40/30/25/20/15/10/6 - $40-$60

#20 uniondrone

uniondrone

    Surveyor 1

  • *****
  • Posts: 1873
  • Joined: 05 Dec 2009
  • Loc: Streetlight Archipelago

Posted 21 April 2010 - 02:16 PM


UO Super Abbe Orthoscopics 24/16.8/10.5/7.7/4.8 - $48

OWL Super Wide Angle 16/11 - $42-$45

Agena AstroProducts Super Wide Angle 20/15/10 - $50

...and depending on where you put the price cutoff:

Orion Expanse 20/15/9/6 - $60

UO Wide Scan 20/15/10 - $60

UO 80 degree 16/11 - $60

There might be some others...

#21 sailor70623

sailor70623

    Gemini

  • *****
  • Posts: 3087
  • Joined: 12 Jan 2008
  • Loc: Ok.

Posted 21 April 2010 - 07:23 PM

Bill & Uniondrone, excellent list. Since you're bumping the $60 range what about the Zhumell Zs (59.98)? And TMB Planetaries ($50)? I know the orthos give better views, BUT the Zs have very comfortable ER, and still give a pretty good view.

#22 Nippon

Nippon

    Viking 1

  • *****
  • Posts: 973
  • Joined: 22 Oct 2009
  • Loc: Central Florida

Posted 22 April 2010 - 10:40 PM

The GSO 15mm Plossl, as someone else commented, is really a sharp eyepiece but it makes no sense to me that they did not put a nice clean field stop in it like the 32, 25, and 9mm GSO Plossls. The 6mm has a fuzzy field stop as well but it is too short for my comfort anyway.

#23 great_bear

great_bear

    Viking 1

  • -----
  • Posts: 989
  • Joined: 05 Jul 2009
  • Loc: Walthamstow, London, UK

Posted 24 April 2010 - 03:11 PM

In TV's case, we don't know the exact design so can't produce the exact spot behavior since it is proprietary.


Bill - Surely the TeleVue Plossl design is something we do know precisely?

http://www.google.co...id=G7MrAAAAEBAJ

#24 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11727
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 24 April 2010 - 03:25 PM

You have a point. But note that the patent application only gives the measures for a 26mm focal length. Exactly what are the curves for all the other focal lengths? Also, as in all good patents, you usually don't give away the farm, so while the curves and spacing of the design are given there, one can bet that the actual production version is probably slightly different...slightly better (even the patent says the diagram and specifications are "illustrative" of the concept, so not to be construed as actual or limiting). So I'm not sure we would be able to extrapolate exactly what the produced 8mm is for example, or all the other focal lengths. Anyway, that's why I said what I did.

But you are right that this might get us close. So would be interesting if someone ran what spots would be for this design in 26mm, vs standard Symmetrical design in 26mm for a range of different focal length systems...f/15, f/10, f/5.

#25 Loren Toole

Loren Toole

    Ranger 4

  • *****
  • Posts: 351
  • Joined: 23 Mar 2004
  • Loc: New Mexico USA

Posted 24 April 2010 - 04:47 PM

I've made one comparison between my flagship low power plossl a Televue 32 mm, and a 32 mm GSO plossl (actually I own a pair of GSOs for my binoviewer). My finding: sharpness on axis was identical, however the GSO showed bloated star images within 15-20% of the field stop. It was noticeable but not really objectionable. Racking the eyepiece in and out of focus clearly revealed astigmatism at the edge, the Televue showed none. This was at f5 which is a very unforgiving focal ratio. The main reason I purchased a pair of GSOs as opposed to a second TV plossl is weight, the GSO 32 mm is the lightest on the market coming in at 4 ounces per eyepiece. The TV is 7 ounces.

In general, I buy Televue in preference to GSO if price is not a factor. The build quality can't be beat IMO.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics