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Matty P
27-09-2009, 04:51 PM
Hi guys,

I'm currently in the market for a new refractor for astrophotography. I'm wanting to get into widefield imaging so I'm looking for a refractor in the 80-90mm range. The two scopes I have been looking at are the Tak Sky90 and the TMB92ss. Heard some great things about both scopes and would like to know if any other IIS members have had any experience with these scopes.

Also I'd like to know any other scopes I should consider having a look at. :)

Thanks. :thumbsup:

Dennis
27-09-2009, 06:31 PM
Hi Matt

I have a Takahashi ‘scope (Mewlon 180) and it is a superb instrument. But, it can be difficult and at times somewhat frustrating when chasing down accessories for astro photography.

Unlike the ubiquitous SCT’s where there are several 3rd party manufacturers of “standard” accessories such as Reducers, Correctors, Flatteners, Camera Adapters, etc., with Takahashi, each family of scopes may have adapters that are unique to those ‘scopes, in order to place the sensor at the correct position.

Although the Takahashi System Charts are very good, identifying the various components required, I have found the accessories to be quite expensive and sometimes difficult to obtain. Needless to say, the build quality is outstanding.

So, take into account the need to accessorise the OTA so you can plan ahead and include the additional costs and potential delays, if any.

Cheers

Dennis

Matty P
27-09-2009, 08:04 PM
Thanks for the insight Dennis. :)

That's quite a turn off for the Tak, however I really don't see myself needing many accessories for it though. Maybe a flattener that is all.

I'm more interested in how it performs optically at this point in time and how it compares to other refractors in its range.

Thanks. :thumbsup:

TrevorW
27-09-2009, 09:08 PM
Try Stallarvue, build quality is superb Peter Read at SDM is the local dist

Cheers

supanova
27-09-2009, 09:37 PM
I would have to agree with Dennis with regard to Takahashi accessories being mainly proprietary and very expensive,although typically good Takahashi quality.As well as being hard to get.And while you may think that you wont need any adaptors,you will probably find you will need a flattener and maybe spacers.As far as TMB is concerned,the older TMB scopes with LOMO or LZOS Russian optics are superb quality,with a great reputation,and available second hand on Astromart,mainly in the U.S.Some of the newer TMB scopes are now sold with optics listed as Thomas Back designed,with the optics actually reportedly made in China,to TMB specs.Quality control is still being debated in various circles.
William Optics scopes are in the same basket regarding quality control.Some are quite OK,and some are below par.But I guess it comes down to what you want and are willing to accept.
I think that the Stellarvue APO's are the best value for money at the moment,and have spent many months researching and reading everything I could find.You can find Stellarvue SV80S and SV80L's on Astromart for under $1000U.S. in as new condition,these are fitted with Russian LZOS optics and are widely regarded as 2 of the finest 80mm refractors made.
I currently own a Stellarvue SV105 LZOS and can vouch for the quality of the optics as well as the overall build quality of the tube and accessories,and they come fitted with a Feathertouch fucuser,which is superb.Where you will notice the difference between a High end Apo and mid rage Apos and Doublet "semi Apos" is in the contrast and better colour correction.

Wayne

Matty P
27-09-2009, 10:00 PM
Thanks for the replies, :)

It looks I'm up for a tough decision.

Initially I was very interested in the William Optics FLT98, however the lack of people using them and quality control issues has me concerned. Also I was not aware of the newer TMB scope lenses coming from China. Which begs the question of the quality of the lenses.

Stellarvue definitely seem to make very high quality APO's. Time to do some reading I think. ;)

Thanks for the help so far. :thumbsup:

AlexN
27-09-2009, 10:24 PM
Im going to put my hand up for TMB on this one.. I appreciate the quality provided by Takahashi, they make awesome scopes... That said, you'd expect to pay as much for the Sky 90 (a doublet) as the TMB92SS... (Triplet) the TMB 92SS will give a wider field, have a faster F ratio, be cheaper to get everything working (ie, 2" push fit extension tubes, field flatteners are cheaper etc...) the Tak focuser would likely be very nice, although it would be a single speed (from memory). The TMB 92SS comes with a 2" feather touch 10:1 focuser.. for photography, thats a big plus..

Not that im biased or anything, but TMB optics are beautiful...

Any reason you're not looking at smaller scopes too? or just prefer the idea of a 90mm over an 80?

Stellarvue.. well.. They are nice. but they are no TMB or Takahashi.. When thinking about some of the nicest refractors around, three names really stand out.. TEC, TMB and Takahashi. To be very honest, Stellarvue scopes are very similar in fit, finish and optics as William Optics scopes.

You could look at William Optics FLT-110.. There were two versions of these made, one had a TEC built lens, the other had a TMB Designed lens built by william optics.. the TEC lens version had superior optics of the two, however the TMB designed lens is no slouch either...

There are a million good options out there.. My overall thoughts are, you cant go wrong with the TMB or the Tak, but the Tak is going to cost you more... first, the scope is more expensive, then the adapters you need, then all the little adapters and spacers etc etc...

Whats the going rate on the Sky 90? And while you're asking yourself that question, whats the going rate on a FSQ85... The babyQ seems to be just as impressive as its bigger brother, the FSQ106.. I think that is one scope you should definitely investigate a little further!! :D

Matty P
28-09-2009, 12:01 AM
After spending a couple of hours doing some research on the BabyQ, I think I think I am in love. :P

The one question I have to ask though is.... What is the BIG difference between the BabyQ compared to a Sky90 or even the TMB92? Apart from being a quadruplet...Is it really worth the extra $$$? Will it yield a better image?

At the end of the day I'm looking for a scope that will give me the best results so maybe the BabyQ seems like the right way to go. :question: Time to start chasing down some prices.

Matt :thumbsup:

AlexN
28-09-2009, 05:07 AM
The biggest advantage is that it will not require a field flattener of any kind... straight out of the box it can throw a dead flat field across a 35mm sensor. so even when you upgrade to an FLI Proline 16803 16mp camera, you still will not suffer from curved fields.

The Sky90 will need a flattener, and probably a reducer in order to make it a very good imaging scope, the TMB will need a flattener, however being F/5.2 (or is it F/5.5?) it wont need focal reduction as its already very fast.. The babyQ is F/5 out of the box... Its fast, it has a dead flat field. Its everything the FSQ106 is, minus 21mm of aperture. How many awesome images do you see from the FSQ106?

Hagar
28-09-2009, 09:01 AM
Hi Matty, I cannot speak for the BabyQ but I can say if it is anything like the FSq106 then it is one very impressive little scope. Both visually and photographic wise the field is as flat as a table top without the need for flatteners. Adapters are made specificly for the tak but you can often get away with 2" push in extenders etc. In fact the scope comes with adapters required to use it in the box.
The image circle on the BabyQ is smaller than the FSQ106 but is more than adequate unles you are going to us a full 35mm CCD.

Good luck with your selection....... Tak accessories can be found at very reasonable prices compared to the prices here, so if you go down the Tak line and need some bits give me a call.

Matty P
28-09-2009, 05:23 PM
Thanks for the help Alex and Doug. I found two images on the net taken with a FSQ85 and STL11K and the image was flat. Seems like Tak is way to go despite being quite a bit more expensive. I compared the two prices I found for the Sky90 and the FSQ85... and found the BabyQ to be quite reasonable. Although it may be just outside of my budget at the moment. I think it will be worth it in the long run. Got some serious thinking to do. ;)

One more question... What supplier would you recommend buying a Tak from? AEC who are the local Tak dealers or maybe importing one from OS?

Matt :thumbsup:

Hagar
28-09-2009, 05:37 PM
Matt. a good question, Probably best answered by PM but what the hell. I bought mine from AEC, paid a bit more but have the good feeling that if something goes wrong I have someone to send it back to with relative ease. To me a local warranty is worth the bit extra. They can be sourced from OS but warranty may be a problem. Peter Lee in HK has them but you would need to email him for a price for the OTA Complete, delivery etc and then be prepared to pay GST and some customs charges when it arrives in Aus. He certainly supplies Tak accessories quite a bit cheaper than they can be purchased here in Aus.
His web site is:
http://www.tan14.com/gears.htm

His email: peter@tan14.com


You may be able to work something out with him, who knows.

Matty P
28-09-2009, 07:52 PM
Thanks Doug, I thought that would be the case with warranty when importing from OS. I'd much rather pay extra for warranty than not have it in the case I encounter a problem. Not that I'm planning to with a Tak though.

Matt :)

AlexN
28-09-2009, 09:44 PM
Cant walk past the FSQ series Matty... I'd have one if I could afford it.. :D

supanova
28-09-2009, 10:05 PM
Interesting thoughts extolling the virtues of TMB and likening Stellarvue to William Optics.When infact Thomas Back was in business with Vic Maris and supplied the exact same optics to Vic as Thomas himself was using in the TMB scopes.They used the same focusers except for the machined focuser used in the TMB 105/650.Which you can read John Fords review on Cloudy Nights.Incidently,my SV105 has exactly the same Optics as the TMB in that review,with a better focuser(FeatherTouch) with a thicker and slightly heavier optical tube,and the same amount of knife edge baffles.So for all intents and purposes optically they should be identical,with only human bias,swaying people to certain brand names???Unfortunately people in Australia are persuaded by local advertising,and availability of very limited amounts of brands as to the so called absolute performance advantages of the readily available brands.To say that TEC TMB and Takahashi are the standouts in the refractor stakes ,shows certainly some personal preferences not really researched fully,as any owner of an AstroPhysics or any of the various refractors around the world that use the same russian optics as used in the older TMB scopes.No one denies that all these scopes perform marvelously,and it is only the user and their preference as to how they are used that will seperate them for a given purpose.Then the choice comes down to cost.How can anyone justify nearly $4500 for an 85mm scope when you can purchase a TMB/SV105 $1500 cheaper and complete with Thomas Backs LZOS made optics,or for around the same price an Astrophysics traveller.The same old arguments abound in Australia that happen everywhere.Tak owners say that nothing comes close to a Tak.AP owners say that nothing comes close to an AP and owners of the various TMB/LZOS/LOMO scopes extoll their virtues.Just depends whose hat you like to wear

gregbradley
29-09-2009, 07:23 AM
Not entirely true Wayne.

Stellarvue are high quality scopes no doubt but I don't think Vic always used LZOS lenses. Sometimes he used them, other times I think lenses came from somewhere else etc. For example I don't think LZOS makes fluorite triplets but the 90 has a fluorite triplet. I don't know where that comes from (no doubt a wonderful lens).

As far as Tak goes they don't make their own lenses either so I guess its the same scene. They could change their lens supplier and their customers wouldn't know.

To me the main thing you want is the manufacturer to have proven high standards so you can have confidence that if you buy brand X you will get a reliable predictable level of quality.

That tends to separate the manufacturers apart to some degree.
I am not making any comments about Stellarvue here as I have never owned one adn I am sure they are excellent.

Some early TMBs for example were very heavy. Their lens cell is steel.
I was told once when researching them that his lens cell had started to form some rust. Tak and AP use aluminium.

Also TMBs and APMs must have about 3 or 4 different tube models which is unnecessarily complicated. But I suppose they are servicing their market with different cost options.

But it is true that if get a Tak you won't be disappointed so that makes it a safe purchase of what is after all a very expensive item.

I cam to the conclusion early on in this hobby you are better off taking the plunge and paying for one higher quality scope rather than getting a cheaper one and then not being happy with it and continually trying out other cheaper scopes taking a loss each time you sell. You lose out both financially and satisfaction-wise.

Greg.

gregbradley
29-09-2009, 07:49 AM
A couple of other points here.

Tak scopes hold their value like Televue eyepieces. Really its the intial cost that is the barrier to getting one. Once you have one the resale value is high as the Tak brand means it is always in high demand and holds it resale value better than other scopes including TMB. They also sell fast.

Secondly a Sky 90 and other Tak fluorite doublets are really high end semi-APO. They aren't true APO which mean by definition 3 colours focusing at the same point, as blue is out of focus on these Tak doublets. You'll see that if you image with one. There will be blue halos around brighter stars.

FSQED on the other hand is true APO. Coatings on the FSQED series
are rather harsh on colour in my opinion and whilst teh FSQED is in many ways a better scope than the FSQ106N, (I have had both) the FSQ106N images show richer colour on objects. If you look a the new coatings Tak used on teh FSQED they are a mustardy colour - yellow green. The coatings on other scopes and the fluorite doublets etc were a green colour. I think these new coatings harsh out images a bit.

See for yourself a bunch of FSQ106ED images and compare them to older FSQ106N images. You'll see:

1. 106ED images are sharper but less rich colours and an overall harsh look to the image in many cases.

2. 106N images often show bluish haze around bright stars but lovely rich colours.

I notice Rob Gendler when he images with FSQ choses 106N as his scope and his images are rich in detail and colour.

This is why I ordered a TEC110 fluorite triplet despite having an FSQ106ED which by the way is an awesome scope. I just want that extra richness that fluorite seems to give.

This may not concern you and it is really a very very fine point when you are trying to get the absolute best out of an aperture.

FSQ doesn't require flatteners or reducers - a big plus. It only requires rings.

FSQ really doesn't have any competition in its class except for expensive high end triplets but they need flatteners.

Also F5 and it will illuminate with corner to corner pinpoint stars any chip currently on the market which is not true of virtually any other scope in its class. The colour richness point above is a minor concern and should not stop you from getting one but I point it out in the name of honesty and my evaluation of this scope.

Having said that I am unlikely to want to sell my FSQ106ED and the reducer you can get for it is a marvel of optical engineering.

Noone else except AP offers a reducer that will handle a 16803 chip - noone. Noone else can do it.

SV105 as pointed out would be an awesome competitor but more against the 106N wher the 105 lens has true APO performance
in colour correction but it will need flatteners for larger chipped cameras or DSLRs and will also give a different image scale (a bit more zoomed in - try the free Wodaski CCD calc to see what teh image scale would be.

Also TMB signature series 130s have great reviews and they often go cheap - aperture rules don't forget. APM also are marketing an
astrograph I think it is 100 oddmm for about US$2700 including rings and perhaps a few other bits. The have a name to protect now so
you could get one of those probably with confidence.

I had a William Optics 80mm once and I found it quite lacking in the qulaity department after being used to Taks. I am sure there are good ones out there but again its brand confidence we want isn't it?

Stellarvue have a lot of fans. I thought the 90mm fluorite triplet was a stunning scope. May not be the one if you intend STL11 imaging though.
That limits you to a much smaller number of scopes. The SV105 would be one with the right flattener, FSQ no worries, Taks in general (really needs a 3.5 inch focuser or larger though for STL don't get 2 inch or you'll get vignetting). I had to upgrade my FS152 to 4 inch focuser to use it with an STL11 form the 2.7 inch.


STL11/FSQ is a match made in heaven and will last a long time and is easy to image with.

There was one for sale here by Monte. Is it still for sale?

Greg.

AlexN
29-09-2009, 09:46 AM
Wayne - Yes, Stellarvue use TMB/LOMO and TMB/LZOS optics in some scopes. and at the time, yes, the SV scope would have an FT focuser. There are many good scopes on offer. I did not say that TMB/TEC/TAK were the only top of the line refractors.

A SV scope with a TMB/LOMO or TMB/LZOS is going to be as brilliant as a TMB telescope. This is why I didnt mention Astrotech Engineering and APM.. because they use TMB/LOMO or TMB/LZOS optics, its much of a muchness...

As Greg mentioned, none of these scopes can out perform the FSQ series scopes in terms of flat field and field illumination.

Yes, I am somewhat biased. I love my TMB/LOMO lens... That will not stop me from saying that I'd take an Astrophysics 130mm over the TMB 130SS, or the Tak TOA150 over a TMB 152....

When I stated that SV scopes were more on par with the WO scopes, I was referring to build quality, fit and finish more than anything else.. obviously a SV scope with the 80mm F/6 TMB/LOMO lens will have equally great optics to the william optics 80mm F/6 lomo scope, and mine etc.. at which point, the final fit and finish of scope will make a difference, and the SV scope with a feather touch focuser will be the best option...


I could dribble on for hours...

Kal
29-09-2009, 01:08 PM
As the owner of a Stellarvue refractor, I will have to mention my experience when I first got my scope. There was a small piece of white paint (probably from where the tube screws together) maybe .1mm wide by 5mm long that had found it's way onto the lens, on the inside of the tube. At the time I thought it was a scratch. I rang up Stellarvue and was put through to Vic Marris himself, who gave me some advice on how to rectify the problem. Point being that the quality of service that you can get from Stellarvue will possibly exceed that from TMB or Takahashi, where I doubt you would be able to readily speak to the owner of the company should you have any concerns.

AlexN
29-09-2009, 02:23 PM
That is fantastic that you were able to talk to the owner of the company when they sent you a defective product. No matter how slight, or how easily fixed this defect was, your method of pointing out the companies excellence was to first say "I bought a stellarvue scope that had something wrong with it.."

Takahashi, TEC, TMB, Astro-Physics owners.. Hands up if there was something wrong with your scope when it was delivered?

Kal
29-09-2009, 05:06 PM
As the owner of a new Astro-Physics refractor as well I can tell you that the quality difference between my SV and AP scopes is marginal at best. Both are built to very high standards, and both have superb optics. The suspected defect in my SV90, as I pointed out, was merely a piece of paint that had come loose during the 20,000 kilometers shipping the product went through, and was easily removed.

TrevorW
29-09-2009, 05:31 PM
I thru in the idea of Stellarvue only because for the price they are a good scope.

Personally if I had the money my choice for a refractor would be an A & M 152mm f/8

http://www.astrotech.it/it/prodotti/a&m/a&mapo.htm

If money is not an issue and you are prepared to import try A&M

Takahashi are a nice scope but personally as with Borg I don't like the proprietary set up for accessories and focusers etc

supanova
29-09-2009, 08:13 PM
Greg and Alex,I completely agree,and I don't know anyone that would disagree that Takahashi make beautiful telescopes,and certainly the FSQ series give beautiful flat fields,and I think anyone that has seen images taken by some of the better Astrophotographers using them would agree they can be stunning,that has never been my point.My point was that there are many genuine Apos out there that in the right hands will provide images at least as good.Everyone has their own personal likes and dislikes.People find different different things appealing and annoying ie Flat fields,chromatic aberation etc.Unfortunately,in Australia we are limited to a large degree to the general availability of just a few brands that are imported here,and most people only get to see and feel the quality or lack of in some cases of these few brands.We all get to see on the internet and read in magazines about other,maybe more exotic brands,as not everyone is prepared to part with a lot of money to an overseas company or individual and hoping you have the product arrive or arrive as advertised in condition and performance.
Alex,unfortunately,I think you may have misinterpreted what I was saying about Stellarvue telescopes.I am aware that Vic used LZOS optics in certain model telescopes only,that is why I mentioned the SV105 F6.2,and the SV80L & SV80S,because these all had the optics supplied directly by Thomas Back to Vic Maris when they were in a working relationship together,with both building their own tubes to fit the optics.I am also aware that just like TMB,Stellarvue now use optics from another source.What I am interested in is a comment regarding the fit and fitment of TMB scopes being of a higher quality than Stellarvue.Maybe the 105/650 CNC model is superior,but I think that this telescope is probably built better than any other refractor built before or since,apart from the focuser!!!!TMB in their other scopes tended to use tubes made by Vixen and a multitude of other manufacturers.Stellarvue tubes are made inhouse and individually inspected for defects,and the dew shield comes with a screw on metal dust cap,and not just a push on cap or cheap plastic end cap.And having now owned one for a while,and having seen first hand most of the top brand scopes,I can say that fit and finish on the Stellarvue is as good as any,and better than most.And please don't mention WO in the same breath either performance wise or build quality wise,because they are not in the same class.But I must admit that I haven't personally been able to lay my hands on a TEC 140,but am willing to take the risk and just go on its reputation,and this will more than likely be my next scope to add to the collection.As I don't think I can afford a 127mm dual flourite triplet Stellarvue!
But back to the original question regarding an 80mm refractor for wide field use with a DSLR,I still stand by what I said regarding the SV80L and probably more so the SV80S having faster optics,more suited to short images taken with a DSLR.And with the change you would have left over from not buying the FSQ85,you could buy any field flattener and accessories and probably buy a nice new camera as well.And any report you will find on these scopes will reiterate how well they perform,and there are numerous images taken by people like John Talbot and Tony Hallas that will demonstrate just how well they perform as a photographic platform.And once again,I don't for one second doubt how well the Tak will perform,but at what difference in cost???

TrevorW
29-09-2009, 08:32 PM
Did I mention that my SV80ED fell a metre and a bit, onto concrete the other night the only damage was some paint chipped off the dew shield.

My heart stopped for a moment when it happened

AlexN
30-09-2009, 08:22 PM
Sorry for snipping down the quote, but I figure its better than reposting the whole thing...

Firstly - Magnificent post.. Very well written and full of great, accurate information..

Secondly, I do not mean again to say that the SV scopes aren't a great option. Clearly they are... the 80S and 80L are both amazing scopes.. I've been interested in the SV105 in the past, however I think I'll go for the Astrotech Engineering 105 if I manage to afford one.. :)

I suppose, the best way to say what I've been trying to say (rather inadequately I might add) is, If money is not in question, the Tak/TEC/TMB (and other manufacturers using TMB designed lenses, TMB built lenses etc. there are many) and Astrophysics are the best options...

Yes, the premium you pay for one of these scopes, that may only have marginally better performance and quality when compared to some of the top end WO/SV scopes, is high.. But as with everything.. getting to 90% of total potential is cheap, its that final 10% that costs mega-bucks...

Take building a street drag racing car...
My VL Turbo I built a few years back cost me $22,000 to get it to run a 10.84sec quater mile... According to my mate (who was a mechanic and my guide at the time) to get the car running under 10seconds would take another $20k at least... Top fuel drag cars talk about figures like $100,000 to get 1/10th of a second faster... This philosophy holds true for almost everything...