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sva130t vs svx130t

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#26 Nippon

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Posted 18 July 2019 - 10:25 PM

Okay that makes sense since to my knowledge the FSQ is a dedicated astrograph. And an expensive one so I'm not surprised it would beat a even a good triplet designed for visual and imaging.


Edited by Nippon, 18 July 2019 - 10:31 PM.


#27 213Cobra

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Posted 18 July 2019 - 10:35 PM

Okay that makes sense since to my knowledge the FSQ is a dedicated astrograph. And an expensive one so I'm not surprised it would beat a even a good triplet designed for visual and imaging.

FSQs make very fine visual instruments, to the point that I use a flattener with my LOMO triplets to bring them up to the Taks. I'm strictly visual with two FSQs. Nothing about the FSQ precludes nor inhibits visual use. -Phil


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#28 Nippon

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Posted 18 July 2019 - 11:00 PM

FSQs make very fine visual instruments, to the point that I use a flattener with my LOMO triplets to bring them up to the Taks. I'm strictly visual with two FSQs. Nothing about the FSQ precludes nor inhibits visual use. -Phil

I'm not suggesting otherwise. The poster who replaced a SVR102 with a Takahashi did not say what Takahashi. I wanted to know which model.



#29 rkelley8493

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Posted 19 July 2019 - 12:50 AM

I think Vic is an honest guy, but he's a business man first and foremost, and he's trying to sell telescopes, keep that in mind. The fact the Stellarvue doesn't advertise the ED glass type indicates that it's probably not an attractive choice of glass. If it was FPL53 or fluorite they would certainly advertise that.

I have the SVA130T-3FT, and it is FPL53 glass. It said it was in the spec sheet. Quoted from vendor's website: 

 

Objective Lense Sizes Air spaced 130 mm f-7 fully multi-coated, apochromatic triplet using a unique design with a combination of extra low dispersion and Lanthanum elements. Lens is mounted in an adjustable steel cell. .95 Strehl or better, test report included.
Optical Glass Ohara FPL53

 

Is that incorrect? I sure hope not... I'd be disappointed undecided.gif 

Mine was at .964 Strehl. 


Edited by rkelley8493, 19 July 2019 - 12:54 AM.


#30 rkelley8493

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Posted 19 July 2019 - 12:56 AM

Ok, I feel a little better now. Here's from another vendor's site:

 

SPECIFICATIONS
Aperture 130 mm (5.12")
Camera/Eyepiece Connection 2" nosepiece
Dawes Limit 0.89 arcseconds
Dew Shield Size 168mm
Focal Length 910 mm
Focal Ratio f/7
Free Shipping Yes
Glass Type FPL53
Hightest Magnification 260x
Light Gathering Power 345x
Limiting Magnitude 14.3
Manufacturer Stellarvue
Optical Design Triplet
Tube Diameter 140mm
Tube Length 749mm
Tube Weight 11.2 lbs



#31 ArkabPriorSol

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Posted 19 July 2019 - 01:06 AM

I have the SVA130T-3FT, and it is FPL53 glass. It said it was in the spec sheet. Quoted from vendor's website:

Objective Lense Sizes Air spaced 130 mm f-7 fully multi-coated, apochromatic triplet using a unique design with a combination of extra low dispersion and Lanthanum elements. Lens is mounted in an adjustable steel cell. .95 Strehl or better, test report included.
Optical Glass Ohara FPL53

Is that incorrect? I sure hope not... I'd be disappointed undecided.gif
Mine was at .964 Strehl.


I think just the current SVX130 doesn't list the glass type. But regardless of glass type, I'm sure the SVX is a very fine instrument, and I trust SV figures and tunes these very well. But at that price point ($5k) it opens the door to lots of other very enticing options.
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#32 Nippon

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Posted 19 July 2019 - 01:23 AM

I have the SVA130T-3FT, and it is FPL53 glass. It said it was in the spec sheet. Quoted from vendor's website: 

 

Objective Lense Sizes Air spaced 130 mm f-7 fully multi-coated, apochromatic triplet using a unique design with a combination of extra low dispersion and Lanthanum elements. Lens is mounted in an adjustable steel cell. .95 Strehl or better, test report included.
Optical Glass Ohara FPL53

 

Is that incorrect? I sure hope not... I'd be disappointed undecided.gif

Mine was at .964 Strehl. 

If you saw that on the web site I'm sure it is correct. My bad I guess I missed that.


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#33 rkelley8493

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Posted 19 July 2019 - 01:27 AM

I don't understand all the Stellarvue bashing... I usually don't go off tangent on public forums, but I did my homework before I went and purchased an Apo.

Stellarvue advertises as grinding their own lenses in house which are made of the highest quality ED glasses [i.e. FPL53]. From there, they test the lenses to meet their high quality standards. This includes the Zygo Interferometer testing to meet a Strehl ratio of .95 or better. Once it meets these standards, then it goes on to assembly. After assembly, it goes to the technician for final tweaks and collimation before it is packaged and shipped to the customer.

It may be materials imported from Chinese manufacturers, but it as all assembled and crafted by the skilled craftsmen & women at Stellarvue. I'd much rather pay a little extra for that then an assembly line mass produced product made of the same materials. 

I'll also add that this is the only scope I've owned that I couldn't find a single thing wrong with or anything about it that needed to be modified. Came perfect as is. Keep up the good work Stellarvue!!

 

 

svtest.jpg

stella1.jpg


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#34 Nippon

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Posted 19 July 2019 - 01:43 AM

I've never understood it either. All the bashing seems to stem from Vic claiming they are not rebadged mass produced scopes and some people not believing that's truthful. Personally I believe Stellarvue does things the way they say they do.


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#35 joelin

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Posted 19 July 2019 - 01:44 AM

Takahashi scopes have independently been tested by 3rd parties to exhibit superb polychromatic strehl ratings (>0.98).

But there are far more significant attributes that distinguish a great scope than strehl ratio. Build quality, focuser, tech support, resale value, etc.) I went from having a SVR102 rated at "0.988 strehl" to a Takahashi. The build quality and optics difference of the Tak was very noticeably better. Taks are constructed like tanks. Every detail exudes high quality.
 

After talking to Stellarvue, they assure me they spend incredible time checking the build quality, focuser and provide bottomless tech support. They pay attention to detail. 

 

That being said, I'm still curious how Tak can exceed them significantly....do they have some secret telescope making knowledge that others dont?


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#36 Nippon

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Posted 19 July 2019 - 02:43 AM

The only things I can tell you that I'm certain about is 1) Takahashi refractors are very good. 2) No they do not have any secret telescope making knowledge that they alone know. 3) My Stellarvue 4" triplet is also very good.



#37 Tim C

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Posted 19 July 2019 - 06:03 AM

If you get the SVA130T, I do highly recommend a focuser upgrade.  The 2.5" is good but with the SVA130T you have an extension between it and the OTA.  You leave the extension on for visual but if you want to use the reducer/corrector for imaging, you have to remove the extension which means you have to remove the focuser, remove the extension, and then re-install the focuser without the extension to achieve focus with your camera.  This is a pain if you like to use the scope for both visual and imaging like I do.

 

For this reason, I recently sent mine in for the 3.5" focuser upgrade.  With the 3.5" there is no extension to fool with.  Plus, it is a much beefier focuser.  BTW, my SVA130T is over 98 strehl.  With the same focuser, it's about a $1,400 price difference between the SVA and SVX.

 

Tim

 

edit: Optec also makes their new All-in-One ThirdLynx DirectSync focus motor for the SVX line of focusers.  These focusers don't require a control box which is very nice.  The SVX35 is the model to get for the SV 3.5" focuser (I don't think it's on their website yet but they do show the SVX30 for the 3" model)

 

https://www.optecinc...slynx/19978.htm

 

 

 

 

 

Stellarvue has told me they can still make the discontinued SVA130T w/ 2.5" SV focuser at $3295 with the 0.95 strehl test instead of the current SVX130T w/ 3.5" SV focuser at $4995 thats hand figured to 0.98 strehl. 

 

They can also do focuser upgrades, +$300 for the 3.5" SV focuser or $550 for the 3" Feather Touch focuser. 

 

Would you notice a difference between the SVA and SVX for visual and/or imaging? Would you recommend getting one or the other?


Edited by Tim C, 19 July 2019 - 06:17 AM.

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#38 bobhen

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Posted 19 July 2019 - 07:00 AM

After talking to Stellarvue, they assure me they spend incredible time checking the build quality, focuser and provide bottomless tech support. They pay attention to detail. 

 

That being said, I'm still curious how Tak can exceed them significantly....do they have some secret telescope making knowledge that others dont?

The Takahashi TOA 130 and 150 refractors use “TWO” FPL 53 glass elements in the lens assembly. The SV 130 uses “one”.

 

Consider that Takahashi has been developing and producing high quality optics for over 40-years and were a leader in incorporating Fluorite glass in refractor optics.

 

If you read Roland Christen’s essay about test reports then you should understand that test reports could be manipulated to benefit a manufacture depending on how the test was conducted, etc.  This is why reputation and a track record are important when making a “very expensive” optical purchase. At one time SV offered test reports that did not test the full optical surface, this skewed the test higher.

 

When you talked to SV, what did you expect SV to say, that they only check ever other telescope?

 

Consider that Canon (the large optical company) produces the optics for Takahashi. HERE is a link to a video that you might find interesting.

 

Consider that for years SV promoted (and boisterously) their imported refractor lines as having the best optics, etc. but that now SV feels that they need to do better. Why? Is this just more SV marketing to differentiate SV from other retailers or will these new SVX refactors actually be consistently better? One can say anything on a website. Meeting that high spec is another matter.

 

Consider that it has been less than a year since Vic has been promoting his in-house capabilities. Now, maybe these SV SVX refractors will be great but there just isn’t the multi-decade track record for these new SV offerings as there is with Takahashi.

 

So the Tak TOA has better glass and better color correction and a LONG track record of quality.

 

SV has just started producing high-spec optics in house. Will they be able to consistently meet their published specs and hold the price?

 

In the end, both “should” be excellent. However you need to ask yourself…
1. Do you need the Tak’s better color correction?
2. Does a company’s track record hold value for you?
3. Are you willing to take a slight chance with SV’s new offerings?
4. Do you even need that higher SV SVX spec when a TS Photoline or Astro-Tech 130 F7 can be had for $2,500 less?
5. Can you even interpret an optical test report or know what might be left out?
6. What are your observing and imaging goals?
7. Consider that many people LOVE their SCTs and that SCTs have an average Strehl Ratio in the high 80s and with optics that are a lot rougher than the above refractors.

 

Bob


Edited by bobhen, 19 July 2019 - 07:35 AM.

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#39 Nippon

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Posted 19 July 2019 - 07:49 AM

There is another option for a scope from a company that has a long history building refractors and should do very well for both visual and imaging right out of the box. The only problem is it is a 4" not a 5". The scope I'm referring to is the Vixen AX103s. I've seen an independent test from the German site and it does quite well.


Edited by Nippon, 19 July 2019 - 07:50 AM.


#40 peleuba

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Posted 19 July 2019 - 08:19 AM

I don't understand all the Stellarvue bashing... 

 

The "bashing" is not so much in reference to the current SV offerings, but has its genesis and is a direct result of the historical puffing that has occurred on/off for the last two decades. 

 

Years ago on S.A.A. and later on CN, there was a Canadian gentleman - Clive Gibbons - that used try to determine fact from fiction in regards to StellarVue.  He ended up having to (unfortunately) parse every word from SV.  I learned a lot in those exchanges.  Anyway, this is tame.

 

Sounds like you have a terrific telescope and it sounds like SV is producing very nice lenses in the SVX line.  I look forward to testing one out if/when I get the chance.    


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#41 ArkabPriorSol

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Posted 19 July 2019 - 08:20 AM

I don't understand all the Stellarvue bashing...


Just to be crystal clear, I am NOT bashing Stellarvue. I think they make terrific scopes, and I very nearly bought their new SVX102 until a TOA130 popped up on the used market for the same price. I applaud Vic for finally making their optics in house.

The thing is they also raised their prices, and now they're near a price point of many time honored and loved top refractors: (Tak, TEC, APM, AP).
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#42 gezak22

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Posted 19 July 2019 - 08:33 AM

I wasn't bashing either, and I am certain that either scope will serve Joe well as long as it can illuminate Joe's sensor, the focuser can carry the load, and the mount can carry the scope.

 

But Joe did not seem to understand that there is more to a scope than strehl.


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#43 ArkabPriorSol

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Posted 19 July 2019 - 09:07 AM

After talking to Stellarvue, they assure me they spend incredible time checking the build quality, focuser and provide bottomless tech support. They pay attention to detail.

That being said, I'm still curious how Tak can exceed them significantly....do they have some secret telescope making knowledge that others dont?


I can vouch personally for Stellarvue's bottomless tech support. They're truly awesome in that regard.

But I've now owned both an SV and a Tak, the Tak just seems more robust, more refined. It just works and works beautifully.

There are indeed lots of factors to consider, Strehl ratio is one of the least significant.
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#44 scooke

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Posted 19 July 2019 - 11:42 AM

gezak22 I highly suspect that is true but how do you know if poly strehl/spherochromatism isn't reported on each scope using the same methods under the same conditions?  If we can't rely on the data, we have to rely on our eyes.  Probably a big reason reports from experienced observers are so valued.



#45 gezak22

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Posted 19 July 2019 - 11:59 AM

gezak22 I highly suspect that is true but how do you know if poly strehl/spherochromatism isn't reported on each scope using the same methods under the same conditions?  If we can't rely on the data, we have to rely on our eyes.  Probably a big reason reports from experienced observers are so valued.

Agreed. And those reports support that the Tak is the better scope, although perhaps overkill for what the OP wants to do.


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