GSO superview eyepieces

[mch62]

Does anyone have the 2" 30 , 42 or 50mm Guan Sheng Superview eyepieces. They are available in OZ and have been getting good reviews on CN although the FOV is debatable . I am after an inexpensive 40mm eyepiece for my f6 newt but at this stage don't want to mortgage the house to buy a TV , Axiom , Meade Pentax ect .
Can any one shed some light on these eyepieces and what F/R are you working at with them.
Any alternatives in the 40millish and 55deg+ with acceptable edge sharpness.
MHodson

[rumples riot]

sorry mate can't help here.

Paul

[iceman]

I'd be interested in any replies myself..

A set of the GSO SV's is on my shopping list, from Owl in the US.. Pretty good prices and as Mark said, getting good reviews on CN.

I can't afford high quality pentax, televue's etc and this might be a good cheap way of getting a wide field.

Although as per my barlow thread, I need a good powermate first I think, before I spend money on more eyepieces - especially for any webcam work I want to try and do.

[mch62]

Totally agree with you on the powermate . Beats the hell out of Barlows .
I have sent an e-mail to andrews communications about the eyepieces he is advertising. I buy a few things from him and the units he has advertised for $99 each for 2" seam to be the same.
Have not recieved a reply as of yet , it takes a few days some times , and he is most probably sick of me e-mailing him about when my new Celestron ed80mm arrives.
Will let you know about them when I get an answer.
Mark Hodson


.

[mch62]

Ice man what size Powermate are looking at ?
I assume it is for use with your 10" GSO ?
I have the 2" 4x . It's only draw back is weight. They are big!!
I got the 2" 4x and not the 11/4" 2.5 or 5x because I like to place my 2" eyepieces in it and have nice comfortable eye relief viewing with out haveing to glue my eye to small 10mm and under glass .
I also use them with larger UO 11/4"orthoscopics 25 and 18mm for planetary viewing again with out haveing my eye becoming part of the eyepiece.
Just my 2c worth!
Now I know people will say what about all those extra elements---4 of them + the eyepiece elements, but from my experience and that of others there impact is vertually nill on light reduction . There coatings are excellent , and should be for the price.
There is one alternative and that is Harry Siebert has a copy of the Telecentric Powermates at quite a reduction in price. Not sure what his work is like have not been able to find any one in OZ that has one of his products to try before I buy . These are called Ultra Barlows
Keep saving Mark Hodson

http://www.siebertoptics.com/SiebertOptics-barlows.html

[iceman]

Yes, it will be for my 10" GSO @ f/5, and i'd probably be looking at the 2x @ 1.25".

I don't have any 2" EP's at this stage, and 2x will be a better allround barlow than a 5x, which will require much better seeing in general to be useful.

I just don't like the fact that it's gonna cost me $300 for one bit of gear, just one powermate..

I could get a Telrad, a white-light solar filter and a steadypix adapter for that cost! :(

[mch62]

Know what you mean it took me several months to pluck up the courage to take the Powermate plunge.
I wish the Sieberts ultrs barlows were around at the time as I may have gone that way.

Ditto Aragorn , yes you do have to watch the (7mm or less for the more mature people) , exit pupil diameter with your low power eyepieces . I currently have an old 42mm kelner and it is not a problem in my f6 newt and powermate .

[iceman]

It looks like the Seiberts only have them available in 2".. Do they have a 1.25" adapter in the 2" size?

Is it right that the price is around US$175 for the 2.5x?

I guess that's a lot cheaper than the 2" powermate, but the same cost (roughly) as a 1.25" powermate.

[mch62]

Iceman your 10'Dob would have a 2" focuser I assume so you can use a 2" Barlow and put a 2" to 11/4"adapter in it to use your 11/4'eyepieces. If you look at the Barlow page he has an adapter listed on the page.
Just watch your weight with your set up . The Ultra barlow may come with an adapter : it does not mention it though.

[Starkler]

Im considering getting a 20mm gso superview to fill the gap between my 14mm pentax and the 27mm panoptic.

At such exit pupil sizes my astigmatism is a problem, so perhaps its not worth spending big dollars on another pentax or panoptic.

If its good for the $69 asking price ill be a happy camper.

[Saturn%5]

Hi Starkler, I have that eyepiece it is great in my dob and for the money you can't go wrong.

[Starkler]

I havent't been able to find any reviews online on this particular eyepiece like there has been for the 30 and 42mm two inch versions.

I would love to know a bit more about your experience with this eyepiece.

Hows the eye relief? Is it easy and comfortable to see the entire field of view?

Are stars sharp right to the edge of view?

Do you believe the claim of a 68 degree field of view? ( as compared to 50 degrees for a plossl).

Is the barrel threaded for filters ?

Thanks

[Starkler]

Iceman, check Andrews Comms in Sydney. They have the 1.25' models listed at $69, and the 2" models at $99.

http://www.andrewscom.com.au/site-section-10.htm

I have had good experiences buying mail order from Andrews, just don't rely on them for expert advice as their knowledge is somewhat lacking.

[mch62]

i have a 42mm 50mm gso eyepiece and a 2x GSO barlow on order from Andrews and will let you guy know how they are in my 2 scopes
It may be a week or 2 as I have a few other things coming and am waiting to put them all on the same shipment.

[iceman]

Thanks Starkler, I think I saw them in the latest Sky&Space ad for Andrews.. How's that price compare to getting a set shipped from Owl in the US I wonder..

Maybe Andrew's would drop their price a bit if you were ordering a couple..

[Saturn%5]

Hi Guy.
Well im no expert on these eyepieces but as i said before im very happy with mine.As far a s it being 68deg fov i would say no i think that claim maybe just a bit out maybe 60 or 62 but the view is still quite good,eyerelief is not to bad but ofcourse there are alot better.Sorry i cant help that much but allaround not a bad eyepiece.

[Starkler]

Last I heard they were retailing for $50US, so at $69AU we are getting a great deal, and shipping is obviously cheaper and faster.

I don't see any reason to buy them from Owl.

I have asked around on a few forums.
From all reports these are well made, and perform better than Meade SWA's . As one person put it, comparing against what was previously available, you would still be satisfied if they cost 3x the price.

What GSO really should do is make a 24-26mm 1.25" model to go head to head with the 24mm teleview panoptic, to give the maximum possible fov in a 1.25' format.

[Starkler]

Placed my order today for a 20mm superview.
Hopefully in about a week I can give a report on it.

[iceman]

Did you order it from Andrews?

Can't wait to hear/read your report.. write a report, include some pics, and i'll chuck it up in the (upcoming) reviews section!

[mch62]

Placed my order for the 42mm and barlow on Tuesday AEST hope to have it for the week end and will give a report early in the next week. I actually wanted it for my Celestron 80mm ed refractor but as I still don't know when it is coming will use it in my 12.5"f6 newt instead . This will be a good test on a faster system for edge performance anyway. At 42 mm I am right on the 7mm exit pupil so it will be interesting to see how it performs .
I currently have a cheapy 42mm kelner design (realy crappy it was given to me) and don't have problems with the secondary shadow in it so here's hoping?

[mch62]

Yes order it from Lee Andrews .
I will only give a brief review next week as I want to give a through one when my refractor turns up as i feel it will give a better all round test .
Speaking of the refractor I will do one for it , as it is an unknown quantity both here and the States .

[iceman]

Sounds great Mark, can't wait to read how it performs in a fast scope.. cause mines an f5 and I'd like a nice widefield for my scope but can't afford naglers and the like.

[mch62]

If Saturn%25 is OK with I will try it in his f5 also and see what the results are but at f5 the max eyepiece for a 7mm exit pupil is only 35mm so it is going to be wasting light and the central obstruction will most probably show up ,but what the hell Igive it a go.

[Starkler]

Yes ordered from Andrews.
I also rang Bintel to enquire about their price as I also wanted to obtain a lenspen which Andrews dont carry.
The lady from Bintel quoted me $109 and when I mentioned Andrews price she sounded quite annoyed and complained "We're in the city and pay $100,000 rent here".
Sorry lady thats not my problem !

If you want to see what they look like ......
http://hardinoptical.com/sv20.html

[mch62]

I have the 42mm superview and the barlow in my hand and will attempt to do an initial testing this week end. That is if the weather will behave .
Since I finished my scope nick named the Rainmaker I have had about 3or4 nights that have been suitable for viewing ,what with the bush fires and now the rain and clouds >>>bugger bugger.
Fingers crossed for a clear week end.

[Starkler]

Got my gso 20mm superview today and it brought the clouds with it

It appears to be well made and a little short on eye relief for one used to using pentax xl's. That is , one needs to jam ones eye right onto the rubber cup to take in the entire field of view.
My guess is that the eye relief is around 10mm.

One neat feature is that if you unscrew the barrel, the whole lens subassembly pops out for easy cleaning.

I'll do a more substantive review once ive had it out under the stars.

[Starkler]

I just gave my 20mm gso superview a very quick first light, comparing it to the 20mm plossl originally supplied with my GS 250mm dobsonian.

The night was cloudy and I was able to peer through a gap long enough to do a quick test viewing of the cluster M7 in Scorpio.

Now for what everyone wants to know, how good is it?

It has a wider field than a 20mm plossl. Im not able to quantify this without doing a star drift test, but as a guess its something like 60-65 degrees.
On axis it appears to perform well , focussing sharply, but the bad news is that the extra field over the plossl comes with a cost of distortion and astigmatism, manifesting itself as classic "seaguls" in the outer 20% or so of the view.

As a person used to using pentax xl's and teleview panoptics, I cant say that the GSO comes close in performance at f5, but at $69 one cant complain too much.
When the moon comes back I'll see how it goes for ghosting and internal reflections.

Strengths :

Well made, fully multicoated, lens subassembly comes out for easy cleaning, great price for the build quality.

Weaknesses:

Eye relief about the same as an equivalent focal length plossl, with "seaguls" present in the extra FOV you get over a plossl at f5.

Conclusion:

Great value for money in the budget price range and possibly wont be beaten by anything costing less than six times as much.

In slow scopes I would recommend this eyepiece without reservation, but at f5 if you want stars to look sharp right across the field, I'm sorry to say that there is no alternative to spending a lot of money for a premium eyepiece.

Geoff

[iceman]

Good review Geoff.. it's a tough call for us with f5's.. I mean you get a wider field, but the extra FOV isn't really useable because of the seagulls flocking..

So is it worth it, or is it worth saving your money for a premium?

That the 1.25" you got isn't it?

Mark Hodson has done a review of the 2" 42mm, i'll hopefully be adding it to the reviews section today.

Geoff if you want to add some pics to your review, email me with them and i'll put your review up as well.