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View Full Version here: : Toa130 or mewlon 250


HCR32
24-03-2012, 07:59 PM
If you where going to choice a scope strickly for visual use only what would be a better solid performer out of the TOA130 and the Mewlon?

Lester
24-03-2012, 08:04 PM
Hi, strictly for visual I'd say the Mewlon. For the same money as the 130 TOA you would have a 200mm diameter Mewlon, is that correct? The 200mm diameter will give you over 2x the brightness of the 130mm.

All the best.

Omaroo
24-03-2012, 08:12 PM
If you're interested after this thread matures a little more and you have a few more points of discussion listed, I might have a Mewlon 210 up for sale.

Viewed though my Explore Scientific 14mm 100 deg EP, the Mewlon gives a stunning view. I'm loathed to sell it, but I'm not really using it. It isn't a really a photographic telescope, given its Dall-Kirkhham design, but I know that Dennis Simmons has some cracker on-axis photographs of various objects though his M180.

Anyway - food for thought.

brian nordstrom
24-03-2012, 08:12 PM
:eyepop: Price and performance wise , yes a 2nd vote for the Mewlon , I spent a dark night using a friends one in NZ many years ago and ,, all I will say is WOAW ! :), for visual.
Brian.

gregbradley
24-03-2012, 11:27 PM
These 2 scopes have clear distinctions, the Mewlon has the great reputation for visual but not for imaging (too long focal length and too small a corrected circle although there is a newish corrector for the Mewlon for imaging). The TOA130 would be great for widefield viewing but really strong for imaging.

Greg.

Waxing_Gibbous
25-03-2012, 12:27 AM
I currently have a TOA 130n and have owned a Mewlon 250.

If I were to have one scope it would be a Celestron 11 or Meade 12" or an Intes-Micro "X"15 if you are happy with a Mak.

For a refractor, a new I-Star 200 or Meade 152/178 ED APO from the '90s will give very satisfactory views (97%) for 1/4 the price of a TOA 130.

The TOA130 is an excellent, colour-free telescope, but better suited to AP than visual (IMHO).

The Mewlons are (again, IMHO) a waste of money. They are difficult to collimate and go "off-song" very quickly.
Also, the spikey artifacts are very noticable in visual use and the wave front error is nowhere near as good as claimed.
Virtually any Celestron or Meade SCT is a match for a Mewlon I think and there are quite a few refractors in the 120-140mm range that will out-perform the TOA visually.
But: YMMV!

G'Luck!
Peter

Logieberra
25-03-2012, 06:20 AM
Our friend, Peter Tan, is selling a used TOA-130F.

http://www.tan14.com/Pre-used.htm

The M250 would also be a lovely choice. Newt, RC, DK, CDK, they're all gonna require collimation of some description. Easily tweaked on a bright star...

Logieberra
25-03-2012, 06:25 AM
P.s. side by side tests of Mars on Friday night here in Canberra, mates William Optics FLT110 and my M210. No comparison. I'd go the M250, extra aperture for visual!

strongmanmike
25-03-2012, 07:40 AM
Yeh? I find that an interesting statement, the TOA is a top of the line APO so while other APO's may give similar views I can't imagine other APO's of the same size out performing it :shrug:

Mike

bert
25-03-2012, 08:29 AM
Speaking of collimating.... If the the toa130 goes out of collimation, be prepared to send to Japan to get it fixed. It has 2 sets of collimation screws for different elements in the triplet design.

At least the Mewlon you can collimate yourself.

Brett

issdaol
25-03-2012, 10:37 AM
I have used the TOA130, Mewlon 250 and I currently own the Mewlon 300. I have also owned Celestron CPC1100 and 2 different Meade SCT's.

IMHO there is simply no comparison between the visuals of the Mewlons and either Celestron or Meade SCT's. While my SCT optics were good samples they just did not come anywhere near the Mewlons.

Also the Mewlons are pretty easy to collimate especially using the Tak Collimation scope so make sure you buy that. My Mewlon 300 gets carted around with me and has not moved out of collimation for a long time.

Visuals through the Mewlon are very sharp with a deep black background. Dark site observation is outstanding. Lunar observation with the Tak 300 and 50mm 2inch EP is fantastic. Planetary views amazing.

Only thing to watch out for is if you are looking for immersive wide field views then the TOA130 or a good Quality NEWT will be better. Although I am very happy with mine as the other visuals make up for it.

Also if you want to progress to CCD work again the TOA130 would be better.

As for which Mewlon, definitely the M250 is optimal choice as it has a fixed primary mirror and electronic secondary focuser (similar to the Mewlon 300) the smaller Mewlons do not. The M250 is also pretty easy to cart around and mount.

gregbradley
25-03-2012, 12:02 PM
"there are quite a few refractors in the 120-140mm range that will out-perform the TOA visually.
But: YMMV!

G'Luck!
Peter[/QUOTE]"



I wonder if you have an out of collimation TOA130. I would be stunned if there were any other scope of the same aperture - AP included, that would outperform a TOA130 to any degree. Unless you prefer high mag views and then 130mm would be a little small perhaps.

If you check out Mr Rohrs APO testing site you will see TOA130 optics are amongst the absolute very best ever.

Like .99 or .98 strehl for every colour channel. That is up with or past AP quality. And practically impossible for a future scope to top because there's virtually no margin left to improve on.

TOA design though is very demanding of perfection in spacings and collimation. ExFSO (Peter) on this site though had a lot of trouble with his TOA130 so there must be the occassional bum one around.

I personally am not a fan of widefield APO views, they are engaging for half an hour and then I want to look at something more closeup. So an SCT or Mewlon would be great for that. And the go-tos of Meade and Celestron are so user friendly.

Greg.

Waxing_Gibbous
25-03-2012, 01:04 PM
Hey Mike.
I've come to this conclusion after doing a few side-by-sides with other 'fractors namely:
A TEC 140, an APM/TMB 130/1200, a TMBSS 130 and a TS130.

The TEC and APM 130 were an easy match for the TOA and both out-resolved it on Jupiter and Luna using a Tak 7.5 LE eyepiece (which I pretty much carry around with me as its THAT good). The APM was certainly as well colour-corrected and both the TEC & APM scopes had a noticably darker background. However both scopes cost as much if not more than the TOA.

In 2010 I took the TOA to Europe and met up with a bloke with a TS 130. It did not 'beat' the TOA, but certainly matched it's resolution and was only a little behind in colour fidelity. At around 1/2 the price (at the time) I was seriously considering a switch!

The TMB SS was an early model from before TMB passed away and really gave the TOA a run for it's money (though at the time there wasn't a whole lot of difference in price). Like the TS scope it was 50/50 - whichever scope I looked through I liked best. The TMB gave better wide-field views tho'.

When first introduced the TOA 130 certainly had a place of its own and still is probably the best colour-corrected refractor around.
However in terms of outright resolution its matched and beaten by several other scopes costing a few hundred or even a thousand bucks less.

Its also built like a tank as they say.
Big chunky metal parts that don't fit especially well and heavier than necessary! :lol:

Anyway. I think there are better visual 'fractors out there for a whole lot less so I'd shop around.

Waxing_Gibbous
25-03-2012, 01:41 PM
I wonder if you have an out of collimation TOA130. I would be stunned if there were any other scope of the same aperture - AP included, that would outperform a TOA130 to any degree. Unless you prefer high mag views and then 130mm would be a little small perhaps.

If you check out Mr Rohrs APO testing site you will see TOA130 optics are amongst the absolute very best ever.

Like .99 or .98 strehl for every colour channel. That is up with or past AP quality. And practically impossible for a future scope to top because there's virtually no margin left to improve on.

TOA design though is very demanding of perfection in spacings and collimation. ExFSO (Peter) on this site though had a lot of trouble with his TOA130 so there must be the occassional bum one around.

I personally am not a fan of widefield APO views, they are engaging for half an hour and then I want to look at something more closeup. So an SCT or Mewlon would be great for that. And the go-tos of Meade and Celestron are so user friendly.

Greg.

Greg.[/QUOTE]

Whatcha Greg.
Actually its perfectly collimated (or better be!) as I sent it to Takahashi for a tune-up just in case the travel had damaged it.
I'm not ragging the TOA by a long shot and I do agree that its colour rendition is the best out there, but its not necessarily apparent in visual use.

One other factor mitigates it's usefulness for me: at f7.7 it's neither fish nor fowl.
Not long enough for top-notch planetary or lunar viewing and too long for good wide-fields.
Though you can add extenders/reducers (I have both), these are expensive and just one more thing to fiddle with.

It's weight is also a factor or rather a mixed blessing. While it's a bit of a pig to haul out every time, its also rock steady on an HEQ6 or better and doesn't budge in even the strongest winds (a BIG plus where I live) which is why I hang onto mine!

I was kinda sad to sell my Mewlon, but it just didn't work for me.
My IM815D gives superiour views of the moon and planets and I've only had to collimate it once in about 18 months.
Mind you - it's twice the price of a Mewlon so it darn well better behave itself!

Exfso
25-03-2012, 02:14 PM
I have a TOA130F and I reckon it is superb visually as well as for photography. I have had issues, but these were my own fault, once it came out of the mount and crashed to the floor of my obs, where I saw my life flash before me, the other time, also my own fault was when I did not check the clutch tensioning on the mount when I closed my obs roof and the whole scope slipped through the clutch and belted into the roof of the obs. This would not normally have happened, but I had totally out of balanced the setup by removing my guide scope an ED 80.
After the second debacle, I decided at the recommendation of the Aust Distrubutor to get a mob in Sydney to re collimate it, and that is the subject of another thread here. Suffice to say they totally stuffed it up and it had to go back to Japan for a complete rebuild. Now I have it back and it is to quote My Takahashi contact, as good as a brand new scope. They are bullet proof almost, but wont stand the treatment I accidentally gave them.
In a night of almost perfect seeing, I had a 5x powermate and the Tak 7.5 eyepiece viewing Saturn at Paul Hease's place a couple of years ago, and the image filled the field of view, it was absolutely superb. So in my opinion they are also an excellent telescope visually as well as for photography.
I must admit though the 4" focuser F version is better than the 2.7" S version, I think this focuser is much more robust and also has the camera rotator standard as well, which is a huge plus.

gregbradley
25-03-2012, 02:37 PM
Whatcha Greg.
Actually its perfectly collimated (or better be!) as I sent it to Takahashi for a tune-up just in case the travel had damaged it.
I'm not ragging the TOA by a long shot and I do agree that its colour rendition is the best out there, but its not necessarily apparent in visual use.


I have never looked though one so I can't comment on its performance
beyond TOA seems extremely sharp in images posted. I do know it is fuzzy in its required aligments compared to say an oiled or air spaced triplet. But your experience seems different to EXFSOs with regards to visual. The possibility exists your TOA needs an adjustment.

Tak do charge a lot for their accessories. But I suppose they are high quality

Greg.

clive milne
25-03-2012, 02:44 PM
For visual use, neither of these scopes would be on my list.

A fast 20" SDM (with good optics) would eat their lunch in pretty much any context you could come up with by a very big margin.

Poita
25-03-2012, 03:14 PM
I agree, if it was for purely visual, I'd be getting a bigger scope.

HCR32
25-03-2012, 03:56 PM
A bigger scope isnt the answer for me. Im not after the resolving power of a big scope im after that sharp crisp view only quality refractors can give and many people out there will know what Im talking about. I once and still till today have and had big scopes but refractors just do something the other designs cant, why I put the mewlon in the mix is because its know to give refractor like quality visual image at the ep. Sharpness is the name Im not after somthing that give soft detailed views where your forever focusing thinking is this better or is it the atmoshpere. I dont want to stir up a war here but Im only asking about two scopes that I have in mind and was hoping people with experience with them could help me out.

gregbradley
25-03-2012, 04:20 PM
Mewlons views are often described as APO like.

But really they are 2 different beasts with long focal length in the Mewlon and short focal length in the TOA. I suppose you can use a Powermate but still its not the same 10 inches versus 5.

Greg.

Poita
25-03-2012, 05:02 PM
Well, in that vein I finally got to put my Lomo side by side with the TOA and there was nothing at all in it. Haven't looked through a Mewlon.

beren
25-03-2012, 05:28 PM
Tough choice went through the same dilemma not long ago :P Went with the M250, the introduction of the new {baffle}corrector swayed it for the imaging angle. I brought mine second hand and arrived with the collimation out a fraction. Collimating at first seems daunting on the mewlon going by the instructions found in the manual but it's not to bad {and seems to hold well moving the scope from storage to backyard}, wish Tak could centre spot the secondary so you can utilise their collimating scope. Unfortunately the few nights I've done visual with the scope I have not taken notes but from memory I couldn't be happier with it's performance {taking into account seeing conditions, cool down etc etc}. Pleased to find off axis views through the eyepieces I use display negligible coma {24pan,16mm/9mm nagler,12mm radian}. Different story for imaging though even the older reducer/corrector doesn't eliminate it, yet to purchase the new corrector.The M250 motorized focuser works fine and easy to access the primary for cleaning, and the back of the scope can be taken off for cooling. Overall no regrets on the purchase, the more all round function of the M250 won it for me but i'd love the privilege of owning a TOA-130 just have to win lotto first.



Agree with you Peter with the spider vane affects, quite noticeable after using SCT's and refractors. Curious why your opion of the mewlons deteriorated after a earlier posting on the 20/2/10 where it was more positive....

alocky
25-03-2012, 05:55 PM
Funny thing is, that advice came from someone who has owned one of the most 'revered' APOs of all time, and who can be counted amongst the most experienced observers in the country. A longer f ratio newt will easily give 'APO' like perfomance if you put a bit of effort into eliminating any stray light via baffling. Still it's your money, and you need to buy what makes you happy, however you rationalise it. Owners of Italian cars and motorcycles are especially good at it! ;)
cheers,
Andrew.

HCR32
25-03-2012, 09:23 PM
Guys read the title "TOA 130 or Mewlon 250"! Im not interested in SDM, cars or motorcycles, thou Im sure there are great things to say about all of them.
Input on the particulars will answer future questions on the matter and Im proud an Australian forum can supply that!

UniPol
25-03-2012, 11:15 PM
I went through this exercise around five years ago wanting a quality 5" refractor and an 8" to 10" cassegrain. I settled for a like new second hand TOA-130 and still marvel at its sharpness and contrast, a real keeper. I very nearly bought a Mewlon 210 to complement the TOA however, at the time, a new CN-212 was on offer so I decided to go with it instead. The CN-212 has an 8 1/4" parabolic mirror and in newtonian mode is f3.9 and cassegrain mode f12.4. As in the case of the Mewlons, you can't escape the little spikes on star images owing to Taks' rather thick spider vanes however you do gain much greater brightness on DSO's.

Richard Kinsey
26-03-2012, 06:09 AM
For imaging/planetary observing, go for the TOA
For deep sky observing, go for the Mewlon

I have had both and I don't think that you will be disappointed with either.

Richard

alocky
26-03-2012, 09:50 AM
In that case, the consensus has it. The Mewlon's superior light gathering will definitely be an advantage, and I suspect you will prefer the extremely narrow field of view offered by the longer f ratio.
Or, get both.
Regards,
Andrew.

Waxing_Gibbous
26-03-2012, 04:59 PM
It took a little while to sink-in. If I had perservered with it, I might have come to fancy the Mewlon, but I'm dead tired of equipment that needs a lot of fussing and the Mewlon needed fussin' with (collimating) all the time.
Another issue was the collimation screws (self-tappers ?!?!) actually SQUEEKED!!!! and the focuser was quite 'grindy'.
Optically. no complaints.
Just not noticably superior to a good SCT.

HCR32
26-03-2012, 07:16 PM
Thats what I thought to. I was told m250 hold collimation very well and really only go out when handled poorly!

UniPol
26-03-2012, 07:44 PM
What is an M815D? I'm trying to ween myself off Google.

issdaol
27-03-2012, 12:32 AM
This must not be a M300 or M250 as you can cart these around easy with little need of collimation. My M300 has been moved in the back of my 4WD to dark sites many times and collimated once.



Interesting comment on the optics, maybe you somehow got a bad or damaged sample.

In my experience using both SCT's (good examples of both Meade and Celestron) compared to the M250 and M300, the Mewlons beat them by a significant margin for sharpness and contrast at the eyepiece . Other Mewlon 250 and 300 owners I know in Australia and overseas say exactly the same.

Logieberra
27-03-2012, 07:12 PM
M210 owner here, it holds collimation well! If you want to pay 2.5x more $$$ for collimation that never moves, go the 250. For any more M210 bashing, let's start a new thread and discuss. HCR23 is not interested in this model... Logie.