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80mm f/6 FPL-53 doublets in the US?

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#1 Jarrod

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Posted 07 November 2013 - 02:04 AM

Looking for something with ~500mm FL. Are there any, anymore? I'd rather not import one. The Orion EON was discontinued and so far I can't find the SW Equinox here. I see that Orion recently put up a 110mm F/6 FPL-51 under the EON name ($1300), but I'd like the better glass, and something smaller and easier on the wallet. What are my options?

#2 T1R2

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Posted 07 November 2013 - 02:36 AM

IDK, but Stellarvue makes a 80ED doublet for 499$ for stock focuser and 699 for their 2 speed, they don't say what glass it is, but these are excellent scopes. and of course they have a 110ED doublet also for 995$ or 1295$

#3 Jarrod

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Posted 07 November 2013 - 02:43 AM

It's an f/7. If I were willing to accept that ratio, then probably I'd just go with the SW Pro f/7.5 FPL-53 doublet on sale for $579 right now.

#4 nicknacknock

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Posted 07 November 2013 - 05:19 AM

At f6 correction for CA won't be perfect with a doublet, hence most f6 80mm are triplets.

Stellarvue has a triplet 80mm which I bought and had first light a couple of weeks ago, but you'd be paying top dollar for 80mm. Having used it (only two times so far) I can attest to excellent correction for color, fantastic pinpoint stars, but also the obligatory field curvature when you use eyepieces that yield low magnification / wide field of views.

http://tinyurl.com/namrrz5

With the 31mm Nagler, I get 5 degrees TFOV and FC is not an issue when you settle on a target. Try to pan around the skies and you get a feeling of swimming underwater. Lasts for a second, but it's there.

Orion has the ED80 CF Triplet at a more "reasonable" price and they state that it has a FLP-53 element. There was a review in one of the astronomy magazines a year ago and it was positively glowing, but I don't place much faith in such reviews (prefer real feedback that comes from multiple CN users).

http://tinyurl.com/pkw432e

CS,

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#5 Jon Isaacs

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Posted 07 November 2013 - 06:38 AM

IDK, but Stellarvue makes a 80ED doublet for 499$ for stock focuser and 699 for their 2 speed, they don't say what glass it is, but these are excellent scopes. and of course they have a 110ED doublet also for 995$ or 1295$


You can pretty much figure if they don't mention FPL-53 it's FPL-51 or something very similar.

Jon

#6 jag767

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Posted 07 November 2013 - 07:11 AM

The celetron onyx fits your bill. Sent you a pm about one.

#7 dbowlin

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Posted 07 November 2013 - 07:15 AM

WO GTF 81 @ Agenastro.com . It is a good one. I like mine.
Dale

#8 nicknacknock

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Posted 07 November 2013 - 07:18 AM

Nice review of the Onyx in Astronomy.com

http://tinyurl.com/n5ng7h9

#9 nicknacknock

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Posted 07 November 2013 - 07:19 AM

And one for the WO GTF

http://tinyurl.com/oyzujgo

#10 RTLR 12

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Posted 07 November 2013 - 07:29 AM

My Onyx 80 EDF @ f/6.25 has less CA than my Stellarvue SV115T20 APO with no name glass.

Stan

#11 nicknacknock

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Posted 07 November 2013 - 07:34 AM

My Onyx 80 EDF @ f/6.25 has less CA than my Stellarvue SV115T20 APO with no name glass.

Stan


Stan, I thought those SV115 were advertised as "superplanetary blah blah" and as true APOs. They suffer from CA???

Please share any insight you have as it is a scope I entertain on and off to get...

#12 jag767

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Posted 07 November 2013 - 08:04 AM

Isnt the gt81 a triplet not doublet?

#13 RTLR 12

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Posted 07 November 2013 - 08:05 AM

Nicos,

I'll send you a PM.

Stan

#14 BillP

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Posted 07 November 2013 - 09:15 AM

The celetron onyx fits your bill. Sent you a pm about one.


Very true...this is one wonderful scope. It is so very very hard to coax any CA out of it also, even on brightest objects. It is a surprising performer too, even at highest magnifications. It easily kept pace all the way into planetary magnifications with an 80mm premium triplet super APO I had too. Only oddities about it are that the dew shield sometimes does not stay extended when pointed at the zenith and if you use a 2" diagonal I have come across a few eyepieces that do not come to focus. I eventually sold my $1000+ premium 80 and kept the Onyx and have NEVER looked back :grin:

#15 jag767

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Posted 07 November 2013 - 09:30 AM

The celetron onyx fits your bill. Sent you a pm about one.


Very true...this is one wonderfule scope. It is so very very hard to coax any CA out of it also, even on brightest objects. It is a surprising performer too, even at highest magnifications. It easily kept pace all the way into planetary magnifications with an 80mm premium triplet super APO I had too. Only oddities about it are that the dew shield sometimes does not stay extended when pointed at the zenith and if you use a 2" diagonal I have come across a few eyepieces that do not come to focus. I eventually sold my $1000+ premium 80 and kept the Onyx and have NEVER looked back :grin:


Couldn't agree more. The only reason I am letting mine go is I use my ed100 when I'm home or going local, and I like my 65mm for travel. If I was into astrophotography then it would have a use for me but as it is I don't really use it. I'd like to see it get a home where someone will appreciate it. Mines also custom painted gloss black and blue metallic :grin:

#16 Jarrod

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Posted 07 November 2013 - 10:13 AM

The Onyx is discontinued, like the EON. These little Synta scopes get glowing reviews every where I look. Why in the heck did they discontinue them in the US?

#17 nicknacknock

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Posted 07 November 2013 - 10:14 AM

Couldn't agree more. The only reason I am letting mine go is I use my ed100 when I'm home or going local, and I like my 65mm for travel. If I was into astrophotography then it would have a use for me but as it is I don't really use it. I'd like to see it get a home where someone will appreciate it. Mines also custom painted gloss black and blue metallic :grin:


Just checked your ad and that's a great paint job! :bow:

#18 jag767

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Posted 07 November 2013 - 10:20 AM


Couldn't agree more. The only reason I am letting mine go is I use my ed100 when I'm home or going local, and I like my 65mm for travel. If I was into astrophotography then it would have a use for me but as it is I don't really use it. I'd like to see it get a home where someone will appreciate it. Mines also custom painted gloss black and blue metallic :grin:


Just checked your ad and that's a great paint job! :bow:


Thanks! there's only one tiny imperfection in the whole thing and its covered by the tube rings.You should see it in person the paint is so much more vibrant the pictures really dont do it justice. My latest addiction has been custom painting refractors. Gives them such a unique look and higher quality finish!

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#19 jag767

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Posted 07 November 2013 - 10:21 AM

One more

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#20 Jim7728

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Posted 07 November 2013 - 11:11 AM

Here you go.

http://www.telescope...of625doublet...

#21 Jarrod

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Posted 07 November 2013 - 11:23 AM

Thanks, had not seen this one. However, it's the same price as the Orion FPL-53 triplet, so hard for me to justify (same comment with the WO).

#22 FirstSight

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Posted 07 November 2013 - 11:30 AM

If your requirements are flexible enough to go up to 90mm, another gem is the William Optics Megrez-90 doublet, which uses FPL-53 glass and is f/6.2. Although like the Onyx it too is regrettably discontinued, Megrez-90s periodically come up for sale used on A...a...you knowwhereImean. The scope is also reasonably lightweight for 90mm, coming in just over 7 lbs.

The only reason I don't use my Megrez-90 as much as I once did is that I got a Televue NP-101 - but just recently I used the Megrez 90 frequently over the nearly three weeks my NP-101 was off at Televue for servicing, and was reminded just how good the optics of the Megrez-90 really are. Yeah, bottom line is that my particular Megrez-90 is unlikely to ever go up for sale (too valuable as a backup for situations or times when I can't or don't want to bring the NP-101 along) but with a bit of patience, you can probably still find one for sale (ditto for the Onyx).

#23 rockethead26

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Posted 07 November 2013 - 12:35 PM

Here you go.

http://www.telescope...of625doublet...


Looks like the same scope distributed by TS in Europe. It's a nice looking scope.

#24 jrbarnett

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Posted 07 November 2013 - 12:45 PM

What about the AWB Celestron 80ED deal?

http://store.astrono...oduct_info&a...

At f/7.5 (a little longer than you asked for) it will have better color correction than at f/6 and it is FPL-53 as you requested.

- Jim

#25 Jarrod

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Posted 07 November 2013 - 02:32 PM

At f/7.5 (a little longer than you asked for) it will have better color correction than at f/6 and it is FPL-53 as you requested.


I knew about this scope but did not realize it had the FPL-53 element. At that price, compromising on focal length could be an option since I could always get the 0.85x reducer/flattener that is (was?) available for these 80mm f/7.5 doublets. But by the time you do that and add in a good focuser you are back up around the price of one of the more deluxe f/6 scopes...there is no free lunch it seems.

One issue I have is that I already made an investment in the Orion flattener for short refractors (the one that doesn't change the focal length) in anticipation of finding an f/6 'fractor for AP. Maybe the simple answer is that I just need to be more patient in the used market. One of the SW Equinox came up on Amart last week but I was too slow on the trigger. In fact I was 0-3 on Amart items last week, which was really annoying :bangbangbang:






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