Toa130 or mewlon 250

[HCR32 (Peter)]

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]

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 (Chris Malikoff)]

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 (As avatar)]

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]

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 (Peter)]

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 (Logan)]

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 (Logan)]

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 (Michael)]

Originally Posted by Waxing_Gibbous

there are quite a few refractors in the 120-140mm range that will out-perform the TOA visually.

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

Mike

[bert (Brett)]

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 (Phil)]

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]

"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 (Peter)]

Originally Posted by strongmanmike

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

Mike

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!

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

[Waxing_Gibbous (Peter)]

Originally Posted by gregbradley

there are quite a few refractors in the 120-140mm range that will out-perform the TOA visually.
But: YMMV!

G'Luck!
Peter

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 (Peter)]

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]

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]

Originally Posted by HCR32

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?

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 (Peter)]

I agree, if it was for purely visual, I'd be getting a bigger scope.

[HCR32 (Peter)]

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]

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.