Talk me out of it

[Dennis]

Hi Matt

I haven’t done any side-by-side tests between the C9.25 and the M180, and since I acquired the M180, the seeing in Brisbane has not been as good as it was when I used the C9.25 to image Jupiter. So, based on more of a feeling than hard data, my impressions are as follows:

On double stars, the M180 is clearly superior to my C9.25. The M180 behaves more like a refractor in that it delivers pin point stellar images with nice diffraction rings and good background contrast, whereas my memories of the C9.25 seem to be filled with more bloated stars and a more greyish, smeared background.

On Jupiter, the C9.25 seems to produce “better” images. That is, the detail still looks nice and sharp at a greater image scale than if I tried to pump the M180 with Barlow’s to achieve the same image scale. So, the M180 simply loses out here in the light gathering department.

I am a little hesitant to commit the above in writing for fear of spooking you! The impressions are just that; a series of impressions and memories as I have never done a side-by-side shoot out. Interestingly enough, Robert, who sold me the M180, when asked about the C9.25 vs. M180 for hi-res planetary work, seemed to favour the C9.25 which is why he parted with the M180. Anyhow, the M250 is a huge light bucket compared to the M180 so image scale should be less of a problem and certainly the Tak mirrors are razor sharp.

When the seeing is poor, say 3 to 5/10, it affects the M180 as much as the C9.25 so there is no real advantage for either OTA under those conditions.

Personally, having now owned an M180, VC200L and C9.25, I would instantly choose the M250 over a 12inch SCT, but I am more of a refractor person rather than a DOB person, which certainly biases my decisions.

Cheers

Dennis

[Omaroo (Chris Malikoff)]

Matt - just buy the damn thing will you! I've never known anyone who has swayed back and forth so much on decisions to buy telescopes! I still have the LX200GPS if you're interested!

Here - planetary on the M250: http://web.gccaz.edu/~pmaxson/planets.htm


Seriously though.... I'd love a Tak Mewlon - just that I think that I'd go full-hog and get the 300. Would anything smaller than the 300, after the 9.25, satisfy to the degree you're after?

Cheers
Chris

[matt]

As you rightly point out Dennis, the greater the aperture...the greater the resolving power. That's a given and a most unvarying fact.

I guess it comes down to what you (or I) want to achieve?

Do I want to compete with the likes of Damian or Mike. Even the word 'compete' leaves me cold. That's not what I'm in this for. So the answer is a resounding 'no'. Not that I could. Those guys are something else and their work is exemplary.

I have never professed to be anything more than a hobbyist (at best) and certainly a run-of-the-mill planetary imager.

However, like most people, I am still keen to produce images which make me happy and of which I can be proud and would like to think the extra $$$$ might be rewarded with an improvement over what the 9.25 is capable of.

I'm not looking to set the world on fire, nor am I looking to re-write the book on planetary imaging.

If the M250 delivers a 20-30% improvement on the resolution and 'quality' of my images and it proves to be a great scope that I can 'grow into' over the next few years...then that'd make me happy.

Cheers

[matt]

Originally Posted by Omaroo

Matt - just buy the damn thing will you! I've never known anyone who has swayed back and forth so much on decisions to buy telescopes! I still have the LX200GPS if you're interested!

Here - planetary on the M250: http://web.gccaz.edu/~pmaxson/planets.htm


Seriously though.... I'd love a Tak Mewlon - just that I think that I'd go full-hog and get the 300. Anything smaller after the 9.25 won't satisfy I wouldn't think.

Cheers
Chris

Well...I'm not sure that's completely accurate. Plenty of folk have asked plenty of questions about all sorts of equipment they are unsure about.

It's a big decision...involving a fair bit of coin (for me, anyway)...and it's just about making the right decision.

Nothing wrong with putting the question/s out there, right? That's what it's all about.

It's OK, though...I know you're just having a laugh. It just seems that way because I've asked the question on a few scopes separately over an extended period of time instead of asking about multiple scopes in the one post.

I'm just taking my time on this. Have spent first and thought later on too many occasions in the past!!

I'd love to buy the M300...but the budget isn't quite there.

Cheers, mate.

PS - thanks for the link.

[rumples riot]

For images taken with the 250 Mewlon go to PVOL. There are plenty of people in Hong Kong, and Asia who are doing fine work with them.

That said the 250 is not a big enough of a step up to get an increase in imaging resolution. Visually it will be superb, but imaging is all about aperture. You get more data and can image at greater focal lengths and hence more detail with larger aperture. That is why I went with the C14 and the SDM in the end.

[matt]

Originally Posted by Omaroo

Seriously though.... I'd love a Tak Mewlon - just that I think that I'd go full-hog and get the 300. Would anything smaller than the 300, after the 9.25, satisfy to the degree you're after?

Chris...you are an evil man.

The seed has been planted.

I'm gonna get a quote on a 300 Just to see what sort of dosh we are talking about.

Problem is...I'd then need to upgrade from my EQ6...

$$$$

[Omaroo (Chris Malikoff)]

Originally Posted by matt

Chris...you are an evil man.

The seed has been planted.

I'm gonna get a quote on a 300 Just to see what sort of dosh we are talking about.

Problem is...I'd then need to upgrade from my EQ6...

$$$$

Uh oh....

If you need the extra cash - talk to nice Mr Bank. i know that I'd regret taking such a huge step up without making it to the top, as it were. If you're going to get into hock - it may as well be good 'n proper.

[ving (David)]

Originally Posted by mill

What the?
But but he has to do it

i was just following instructions... he wants us to "talk him out of it"

[Alchemy (Clive)]

Well as he WANTS us to try to talk him out of it i will try to oblige

1 paying for an expensive brand name
2 small aperture gain
3 Why is it at a very nice price (caveat emptor)
4 Head to head would it beat a sub 1000 dollar 12 inch newt !
5 For the same money you could purchase a verynice mount
6 Whats wrong with the 9.25 almost legendary optics
7 have you used the 9.25 to its full potential
8 perhaps a ccd camera instead mmmm....
9 perhaps another larger scope the taks not the only option.
10 what about an observatory, no more setting up etc
11 have you paid off your credit card

...i could go on......

[spearo (Frank)]

Hi Matt!
what a crack up!
"Talk me out of it" !!!

I think what you really need is what's known in the business as a good "rationalisation" for the purchase. Something to soothe the Superego (Freudian terminology) which is trying to control your desire/impulse to get the dream scope.

I'm here to help (but don't let anyone know i did this):

1) you can justify the purchase by telling your loved one it's to make nicer photo dedications to show the strength of your feelings

2) it's basically a risk free process since you know you could return it if it's not functioning as it should and you know and trust the source (I'm guessing here...)

3) it's basically cost neutral (well potentially) since you could easily resell it if you needed to and we all know great quality scopes hold their value nicely

4) think of how it will eat away at you to not get it. Never knowing if it might have given you that 20 or 30% improvement you are really capable of, this would torment you and make you miserable, might even drive you to drink... think of all the money you'll save on NOT having to buy all that alcohol

5) if you get it it will make you happy and we all know happy people are more productive people. This might mean a promotion at work, better salary, maybe even enough money to ungrade the mount and put the lot in an observatory. Basically it represents an investment in your career and your future

I could go on but i think you should just give it a go.

Argument 2 and 3 above are probably the saner one I can proffer.

And, on a selfish note, I'd LOVE to have a looksy through it myself someday!

Let us know when you've decided.

cheers
frank

[okiscopey (Mike)]

I was reading up about the Mewlons recently. Among glowing reviews, the only negative I've come across is the reportedly limited back-focus of the 250. (I don't know if this applies to the 300.)

The discussion below came from the Tak Yahoo group. It looks like you can fit in a camera, adaptive optics unit and a reducer if you have the right bits and pieces, but I haven't been able to ascertain how difficult this is in reality.

I suppose you've looked into this. Has anyone any more info? If it's not a problem, I'd be keen on an M300 myself.


[UncensoredTakGroup] Re: Mewlon 250

"Well I have had my Mewlon 250 on its EM200 mount for several months now. It tracks perfectly and has tremendous optics. It is a very good visual scope and is fine for prime focus photography where the camera is placed right at the visual back of the telescope.

My biggest concern about this telescope is that compared to my Celestron 9.25" scope it has very little backfocus. I find this to be a really major problem."

"Hi Paul: I forgot to address the back focus so called problem with the
mewlon-250. It all depends on how much stuff you want to hang from the mewlon. There is a low profile adapter for the mewlon-250 for less than infinity and also equipment trains. I have the mewlon-250 and FS-102 on a NJP mount. Also the secondary can be lowered a little closer to the primary for focusing with the longer equipment trains."

"Hi Rick, my push set screws on the secondary are almost flush with the top of the ring. I have a mewlon-250 also and use the optional cassagain focuser/rotator, I seem to have a lot of back focus. The secondary height will help with more back focus, the closer to the primary the more back focus."

"Takahashi makes a shorter version of the 2" ocular adapter that is
about an inch shorter than the standard version."

"I had the same issue with the lack of back focus on my M-250. I
couldn't get my ST-10, AO-7, and reducer setup to come to focus.
After speaking to Fred at TNR, I moved the secondary/focuser unit
back a bit. With this adjustment, and a custom made short ocular
holder, I am able to get enough back focus have my ST-10, AO-7, and
reducer come to focus. I would suggest that you talk to Fred before
making any adjustment to the secondary."

"http://www.astrofactum.de/Astrofactum/index.htm

Using this clamp you will get about 22mm more back focus. It is
designed to hold havy binoviewer or ccd camera equipment in place.
Heiko."

[Dennis]

Just for info’ on my Mewlon 180, I can achieve focus with the following.

• Mewlon 180 threaded back (naked with everything removed).
• Moonlite motorised focuser attached directly to naked Mewlon threaded back.
• Moonlite native 2” focuser exposed (i.e. 1 ¼ reducer removed).
• Takahashi x0.8 Reducer/Corrector. (Push fit into Moonlite focuser).
• Tak TCD0012 adapter/spacer to connect T-Thread on CFW8A to Tak x0.8 Reducer/Corrector.
• SBIG CFW8A colour filter wheel.
• SBIG ST7E CCD camera.

Cheers

Dennis