Astro-Tech AT130 130mm vs Tak TSA 120

[Jutscher]

Hi
I have been been umming and aahing over these two scopes for the past couple of weeks and have decided that I will most likely import one or the other while the dollar is so good. :lol:
I plan to use winner for wide field imaging and although I realise that the Tak will undoubtedly offer a better overall image, is the $1000 price difference worth it (could be used to buy a couple of nice new eyepieces) :question:

At the same time, there is not a lot of good unbiased information available on the AT 130. I believe that it is most likely a GSO in camo however that is not nescessarily a bad thing.

So I would be keen to hear from anyone who has purchased either of these scopes (particulary the AT130 in regards to QC etc) for some feed back prior to making the final decision.

Thanks

[Octane]

Sam,

I know this is easier said than done, but, if you spend the money on the Takahashi, you /know/ you're going to get a product that simply works; it has users, it has history, an endless supply of accessories, and does the job par excellence.

Add in here that if you wish to move into astrophotography at some point, what better scope to image with than a Takahashi?

I understand that $1,000 is sometimes hard to justify, and, is a lot of money. Bearing in mind the favourable situation with regards to our dollar's strength at the moment, I know where my money would be going.

H

[Alchemy]

The tak will hold it's value, I don't think the other will.
The tak is a proven performer, given they have the rebadged rc scopes, it's possible this is as you say a gso scope. I'm a Williams man myself, ( cant afford the tak scopes, would have an astrophysics if money was no object) but the tak has the runs on the board.

[TrevorW]

Sam I'm with H on this one if you can squeeze the old credit card for another grand, well worth going down the Takahashi path. Just to clarify, I don't own one but would like one but have never heard or read a bad thing about one.

A well kept Takahashi is like a BMW in the resale market.

[gregbradley]

I have owned several Takahashi scopes and yes they are pricey but they are sure to wow you. Everything will work, you won't need to modify or correct some deficiency etc and they are just plain nice to have. They ooze quality and competence.

You will however need to buy certain accessories so that $1000 difference may be more than that. For example I bet the AT130 comes with rings - the Tak doesn't. The Tak also will need a finder scope (perhaps the AT will also). A Tak finderscope is about another AUD$250 and the rings perhaps another AUD$325. Although you can use alternatives if you know the tube diameter.

I have an AT66ED and it is a surprisingly good scope. The fit and finish are very good and it has a microfocuser. I believe these are Taiwanese so that is a step up from Chinese.

The AT also comes with a case the Tak does not.

The Tak TSA 120 is an oiled triplet. This is the classic design for an APO made famous by Astrophysics. It is the premium design. Oiled triplet means only 2 air to glass surfaces which means less reliance on the optician to get 6 surfaces perfect - they only need to get 2 surfaces perfect.

I just looked up the AT130mm. It says it is an air spaced triplet and uses OHara glass. That sounds good. But who makes the optics? Air spaced triplets are very hard to make. Easily botched. Are 10 great and then the next 4 no good as they are done by some other guy in the factory or are they simply pumped out by a computer controlled polisher with little input from the worker? Air spaced triplets of quality that I am aware of are either Tak (TOA series), Astrophysics (AP160 a rare scope), or mostly by Russia's LZOS (in TMB or APM scopes mainly). At US$3595 its not a cheap scope either. I know the focuser is probably similar to the AT66 I have. It is a bit loose and doesn't tighten 100% (the locking screw) and it will slip under load (from a camera). Also a 2 inch focuser is way small for astrophotography. 2.7 inch is really the minimum otherwise you are likely to get vignetting in your images. I'd say offhand Tak versus AT is like comparing a VW with a Mercedes. They aren't really competitors as they are in 2 different levels of the market.

Also F6 is good for imaging but not great for visual. The Tak is F8 I assume and a reducer would be available to give it F6 for imaging. That makes it more versatile. Also F6 is a real challenge for the optics. Again you are placing trust in a relatively unproven manufacturer. F6 is a challenge for Tak or Astrophysics let alone AT. The faster the optics the harder it is to make it APO.

Competitors to Tak are Astrophysics, APM/TMB and TEC. For US $5200 you can get a TEC140 - a proven performer or you could pick up a second hand Tak TOA130 which would be unbeatable. There were also some nice 130mm TMBs going cheaply on Astromart quite often like US$2500. There is also a nice APO by APM that seemed good value.

Also as mentioned a Tak scope resells for close to what you buy one new for. You may lose perhaps 15% on a Tak on resale. An AT may lose 30-45%?

Having said all that I suspect the AT is probably overall a reasonably nice scope if my AT66ED is anything to go by.

I had a quick look on Astromart - here you go a TMB 130mm F7 signature series, rings and case US$3600 negotiable so that probably means he'll sell for $3300 or less (the ad was on page 3 so no takers yet). It looks like it has a feathertouch focuser. These scopes got good reviews when they were first released:
http://www.astromart.com/classifieds/details.asp?classified_id=702002

Add about US$350-$400 for shipping and insurance and 10% of the landed cost for GST to get the final cost (same with your AT130 if you are buying from overseas).


Greg.

[Waxing_Gibbous]

My 2 cents here. I have the TSA 120 and coudn't be happier. However this is the 2nd copy as the first one was woeful - worse than any Chinese scope I've used. Fortunately it was quickly replaced w/o fuss by OPT.

The AT 130 is a fairly new scope, but already they are appearing on A-Mart and CN at knock-down prices, leading one to believe that they are perhaps not the AP killers they're made out to be. I believe that AT quality control is quite good if not excellent. Its just that their bar is lower than APs or Tak's or TEC's.
I would steer clear of the TMB 130's as (IMHO) they aren't worth the cash and are merely playing off the Thomas Back name. Quality is variable at best and there are quite a few duff ones.
If a TEC 140 comes up for <5k, buy it!! Its the best refractor I've ever looked through; including its AP competition.
As Greg points out the f6 focal length of the AT is really pretty short for visual use while the f7.5 of the TAK makes it near perfect. Also at just over 6KG (7KG with EP, diagonal and finder)its fairly easy to shift around can still be considered a viable "grab and go" scope.
The (second copy) of my TSA 120 leaves nothing to be desired. Stars are pin-point with near-textbook diffraction rings. Focus is 'snap-to' and it takes rediculously high magnifications with no image breakdown. I have observed (in ideal conditions) the 'E' and 'F' stars in M42 using a TAK LE 2.8 eyepiece and averted vision! The only hint of false colour I've seen is on Venus while it was about 5' above the horizon, so atmospheric interference was the likely cause.
It is without vice as a Lunar scope, easily outgunning my 8" Newt for resolution and contrast.
If it matters, its also an excellent scope for terrestrial observation of birds, animals etc.
So to summarize: With the $ at an all time high, its a perfect time to get a TAK. However these ARE mass-produced scopes (though not on the Skywatcher scale) and mistakes happen, so I would get the dealer to field-test it before-hand just in case.
Hope this has been of some use.
Peter

[Jutscher]

Thanks Peter, Greg, Trevor Clive and Humayan :)

It seems that the general concensus is if you have the money, go for the Tak, and that is definately in line with most of my reading.

Greg, I was of the belief that the Tak 120 was air spaced as well. Have been wrong before tho.

Yeah, the hard case, rings etc had put the AT up a little in terms of value for money, but I am looking for a scope that will last the distance.

The cost of parts for the tak does make it a little exclusive however, you only have to buy them once (hopefully).

Thanks for the tip Peter on asking OPT to test the tube first (that is who I was looking at buying thru), would make sense when shipping from the states.

Sam

[gregbradley]

I just checked the review and yes you are right it is an air spaced triplet.

I read a post by Roland Christen about air spaced triplets versus oiled triplets.

He basically said that air spaced is harder to make (6 glass to air surfaces each requiring exacting work) but it allowed the optician more degrees of freedom for colour correction. For example the AP160 is an air spaced triplet whereas AP scopes are usually oil spaced triplets (as are TEC scope). So again the emphasis would be on the optician's skill.

If a TSA 120 is around the US$4500 area I would go a 2nd hand TEC140, that's an extra 20mm of aperture, it is light and I have yet to hear of anyone who has owned one who was less than rave review happy with it. You often see them on Astromart for around US$4500 and they come with rings. I can let you know if one comes up.

Its not really a question of is the Tak TSA120 better than the TEC140 as both are excellent and aperture rules so the bigger one is usually the better. A 140mm scope is really an ideal size in many ways for both visual and imaging.

It is the AP scope that you can actually get.

Greg.

[MortonH]

What about a Stellarvue 130 EDT?

http://www.stellarvue.com/sv130edt.html

[Jutscher]

Yeah, I did have a look at the Stellarview 130, wasnt to sure about the FPL 51 glass, does that compare well with FPL 53? I wouldnt have a clue.
Will have a bit of a read up on the TEC. Seems everytime I think I am close to making a decision, another awesome APO is suggested. I definately wont be going down the AP route, dont see the point of putting yourself on a ...? how many year long wait list for a scope which when finally produced you may no longer want.
Oh.. and regarding the TOA 130, I had read that it takes a long time to equalise with the ambient temp when compared to other scopes of a similar aperature.
Sam

[gregbradley]

FPL53 is the top glass but you also have to know what the other 2 elements are made out of to maximise its advantage.

TEC160 uses FPL51 glass. I queried Yuri about that and it basically worked out best for that design of lens.

Most triplets though do use an FPL53 centre lens and hopefully something nice for the other 2.

With Stellarvue its a bit hard to evaluate as they source their lenses from other people and don't make their own?? So where are they getting the FPL51 triplet from?

As far as temperature cooldown times for TOA series you can ask on this site as there are several who use TOA130 or TOA150 who could tell you if this is a concern or not. The only place I have heard that comment from was AP Yahoo Group where they are biased against Takahashi as Tak has been the traditional competitor for AP. They would not even know as they would not have owned or used one. I haven't heard any complaints by TOA owners only positive things. One thing I do know is TOA scopes produce some of the highest resolution images of any type of scope for their size and have exceptional, perhaps best in their class colour correction. They are somewhat unbeatable due to their clever design. I also remember reading they have 2 FPL53 lenses not the usual 1.

I know my Planewave CDK17 needs 1-2 hours to cooldown otherwise you can't get a sharp focus and that is kept in an insulated observatory.

I haven't really noticed much of a cooldown time required for my TEC180 triplet, nor FS152 nor AP140 or FSQ106 but I am sure there is one if I were using it visually.

Greg.

[rcheshire]

I have an explore scientific with FPL 51 glass - it's made by Hoya.

[Jutscher]

I think my decision has been made (even my wife is telling me to shut up and just order the thing!). So I will be ordering the tsa 120 in the next couple of days. Can't wait :)

[gregbradley]

You'll be rapt with it.

Looking forward to reading your review of it.

Enjoy.

Greg.

[Jutscher]

So... I have ordered the tak tsa 120 today :D after a final bit of reading. The extra bits cost a little, but it just didnt feel right getting only the OTA.
And yeah, Greg, I will have to have a go at reviewing it when it arrives, any forum links/websites etc that have good guidelines for this (have never written one). I will need to head along to the next club night for some comparisons, as I only have the ED 80 refractor at the moment, wouldnt be very fair.

Sam

[Steffen]

Where did you order it from, if you don't mind me asking?

Cheers
Steffen.

[Jutscher]

AEC in Australia. Cost about $200 more than if ordering from the states (by time you factor postage + insurance + tax), but it means if anything goes wrong, it will be a much cheaper return journey for repair/service, unlike sending to the states for warranty jobs.

[Steffen]

Ah yes. I've had a number of successful transactions with Claude myself in the past…

Cheers
Steffen.

[Jutscher]

The TSA 120 arrived today, its quite a bit heavier and sizeable when compared to my ED80 than I expected. Hope these clouds clear tonight...