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Am I nuts to think of Mewlon 180 when I already have a 4” Tak APO (and a bigger SCT)?

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#26 Kunama

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Posted 13 April 2019 - 03:53 AM

Kiitos Matti - I knew that I could trust you on nudging me off the cliff grin.gif

 

All the sarcasm and jesting aside, the essence of your reply is exactly what I needed and based on experience waytogo.gif And seems to favor my own initial thoughts and alleviate the doubts I had.

Either that or I am just happy to spend your money !!!! cool.gif

 

 

 

 

(I will be in Helsinki in late June/July, also visiting Turku, Tampere, Padasjoki, unfortunately it will be too light for stargazing)


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#27 Kunama

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Posted 13 April 2019 - 03:59 AM

Mounting requirements for visual is a hugely individual and subjective thing. I know I’m at the end of Gaussian curve at CN who tends to overmount for visual. Most people here talk like it’s normal to have the scope shaking for 2 seconds after touching the focuser. I don’t get it at all. Kills the enjoyment of observing for me if the image jumps around for two seconds every time I touch the scope or there’s a lightest breeze.

I have observed with C9.25 on multiple mount and tripod combinations, and have found one that works for me: AZ-EQ6 on Berlebach Planet. The scope won’t mind if I poke and nudge it in the dark, and dampening time after focusing - even at really high magnifications - is zero seconds. That’s the way I like it.

I’m pretty sure I’d be happy with M180 on a lesser mount than that. In addition to weight difference (which would be more than 4.5 lbs since C9.25 requires a dew shield and/or insulation in my climate, although I don’t want to start an insulation debate here), the moment arm is likely more forgiving in M180 because most of the mass ends up closer to mount saddle in all dimensions (smaller diameter tube, no corrector plate and corrector cell at front, no need for dew shield, placing also the primary closer to dec axis once the position is balanced). OK, the dampening time of M180 on EQ5/UNI might not be zero seconds, but I wouldn’t use fully-loaded & equipped C9.25 on it even in my dreams (or, rather, nightmares).

Couldn't agree more, my Mewlon will ride on the AZ-EQ6GT on a Tak EM400 tripod, there is no shaking even when focusing ..... but the tripod does have a 450Kg load capacity !!!! grin.gif


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#28 luxo II

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Posted 13 April 2019 - 04:31 AM

I'm with Axunator - I do not tolerate a shaky setup.  IMHO a large part of the problem with many cheap mounts is a metal tripod that "rings like a bell" ie.  lacks the significant damping which wooden tripods provide.

 

Regarding the Tax vs Mewlon vs a C9.25... Personally I think you will find you don't use of these scopes.

 

When I had 2 or 3 scopes the largest invariably was the one that saw most use, even side-by-side with a second (a 130mm APO was one candidate, a SW 180mm mak another), and I am pretty much down to one serious scope (pictured) plus a small G&G refractor for my son.

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Edited by luxo II, 13 April 2019 - 06:03 AM.

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#29 bobhen

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Posted 13 April 2019 - 06:48 AM

Thanks Bob - good info to base my realistic expectations on waytogo.gif Reasonable cool-down times (like 1 hour) are not a problem even at my downtown backyard. It’s just that there’s absolutely no way to store anything outside, and the gear has to be stored pretty much completely disassembled inside due to space requirements. And the inner-city skies are so compromised anyway, that the setting up and tearing down need to be simple enough for it to be worth it.

Of course I don’t know your conditions or where you draw the line with portability or weight issues but after reading your post I think a Tak TSA 120 on an alt/az mount to use at home might be close to the perfect single-scope solution.

 

Reasonable cool down time
Stays acclimated even in falling temperatures
No collimation or fuss
Excellent performance in compromised seeing
Better deep-sky reach than your current refractor 
13 pounds bare OTA around 18 pounds all up
Excellent for solar observing with Ha or white light filters
Excellent imaging, video or night vision scope
Excellent lunar/planetary performance
Can ride perfectly well on portable alt/az mounts for easy set up/take down
The TSA 120 has superb (again really superb) optics, outstanding sharpness and no color, even in the star test.

 

I observe mostly from the Philadelphia suburbs with mediocre seeing and heavy light pollution. 9-years ago I upgraded from a great LZOS 105mm apo to the TSA 120 and would do the same today.

 

Below is my Mewlon 210 and Tak TSA 120 on an alt/az mount.

 

Good luck with your decision.

 

Bob

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#30 dweller25

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Posted 13 April 2019 - 07:15 AM

I need someone to come here and tell me that the difference in views between the 4” APO and M180 is nil, otherwise I’m doomed.

Well.......

 

I have a 180mm F/15 Russian Mak which I guess will be very close to the performance of the 180mm Mewlon.

 

I also have a TSA102 which cannot match the planetary views of the Mak

 

So.........


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#31 Axunator

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Posted 13 April 2019 - 07:18 AM

Either that or I am just happy to spend your money !!!! cool.gif

 

(I will be in Helsinki in late June/July, also visiting Turku, Tampere, Padasjoki, unfortunately it will be too light for stargazing)

Too bad the bino-TSA or the Excalibur won’t accompany you on your Nordic tour I presume, but star gazing wouldn’t be on the agenda on June anyway, that’s for sure!

 

PM me if you have a free evening in Helsinki and need a pal to have a pint on some nice restaurant terrace. The most beautiful time of the year to visit my current hometown. But you knew that already wink.gif


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#32 Axunator

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Posted 13 April 2019 - 07:44 AM

I'm with Axunator - I do not tolerate a shaky setup.  IMHO a large part of the problem with many cheap mounts is a metal tripod that "rings like a bell" ie.  lacks the significant damping which wooden tripods provide.

 

Regarding the Tax vs Mewlon vs a C9.25... Personally I think you will find you don't use of these scopes.

 

When I had 2 or 3 scopes the largest invariably was the one that saw most use, even side-by-side with a second (a 130mm APO was one candidate, a SW 180mm mak another), and I am pretty much down to one serious scope (pictured) plus a small G&G refractor for my son.

Gotta love those wooden Berlebachs - the vibration damping characteristics are so good that people with experience only on steel tube tripods probably cannot imagine it. And this holds true even for very light-weight wood tripods (which the Planet most definitely isn’t), like the Report. And they are warm to the touch in winter, nice to carry around especially with the spreader installed, and easy on the eye (matter of taste, of course). A natural choice for an European astronomer on the go, probably more exotic to people on other continents.

 

Regarding the different scopes, my most used scope currently is the 4” Tak wink.gif  True, if I’m at a dark site observing DSOs, the C9.25 takes the spotlight, but there’s more than that to the life of an urban stargazer grin.gif



#33 Axunator

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Posted 13 April 2019 - 08:03 AM

Well.......

 

I have a 180mm F/15 Russian Mak which I guess will be very close to the performance of the 180mm Mewlon.

 

I also have a TSA102 which cannot match the planetary views of the Mak

 

So.........

 

Thanks David waytogo.gif Another data point to affirm my initial idea. Those Russian Maks are quite legendary. If Intes Micros were still easily available, a 7” would be a really serious contender for the 180 Mewlon, especially in terms of optical quality.

 

You guys are really determined to lighten my wallet lol.gif


Edited by Axunator, 13 April 2019 - 08:05 AM.


#34 Axunator

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Posted 13 April 2019 - 08:23 AM

Of course I don’t know your conditions or where you draw the line with portability or weight issues but after reading your post I think a Tak TSA 120 on an alt/az mount to use at home might be close to the perfect single-scope solution.

 

Reasonable cool down time
Stays acclimated even in falling temperatures
No collimation or fuss
Excellent performance in compromised seeing
Better deep-sky reach than your current refractor 
13 pounds bare OTA around 18 pounds all up
Excellent for solar observing with Ha or white light filters
Excellent imaging, video or night vision scope
Excellent lunar/planetary performance
Can ride perfectly well on portable alt/az mounts for easy set up/take down
The TSA 120 has superb (again really superb) optics, outstanding sharpness and no color, even in the star test.

 

I observe mostly from the Philadelphia suburbs with mediocre seeing and heavy light pollution. 9-years ago I upgraded from a great LZOS 105mm apo to the TSA 120 and would do the same today.

 

Below is my Mewlon 210 and Tak TSA 120 on an alt/az mount.

 

Good luck with your decision.

 

Bob

Thanks Bob! I do see your point. I just don’t think I’m ready for that kind of move yet... I’ve had the DF in my possession for too short a time. Even if I didn’t believe in ’lifetime scopes’, I do see the value in living with one’s equipment long enough to really learn what it’s capable of, its idiosyncracies, strengths, weaknesses... Especially if the said equipment is as nicely crafted as the Tak. Maybe in a few years I might be mentally ready crazy.gif



#35 gnowellsct

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Posted 13 April 2019 - 08:33 AM

I'm with Axunator - I do not tolerate a shaky setup. IMHO a large part of the problem with many cheap mounts is a metal tripod that "rings like a bell" ie. lacks the significant damping which wooden tripods provide.

Regarding the Tax vs Mewlon vs a C9.25... Personally I think you will find you don't use of these scopes.

I've used a Berlebach Planet regularly since 2007 but this view about the primacy of wood is over simplified. The Losmandy hd is aluminum and as solid or more so. The Tpod 110 is aluminum and as solid or more so. (The HAL vixens are well reputed but I haven't owned one.) The ATS pier is aluminum and also as solid as the Berlebach. I own that too. 10micron also has a superb aluminum tripod which I saw at NEAF but I don't own.

The reason to go with wood is that in freezing weather you don't have brutal skin contact problems. Even so I chose the Tpod for the dm6 because it is lighter and faster set up.

I agree with requiring zero damping time for performance. I use my tripods with g11, Dm6, and ap900. The ap900 is excellent on losmandy HD and ATS.

A bouncing scope makes focusing difficult. The whole reason we're out there is to get the object in focus. And it interferes with observing too.

Anyhow berlebach is a competitive and attractive top tier tripod but aluminum alternatives are too. Stability lies in design and execution.

I use my scopes two at a time and solo. I don't always go for the 45 minute setup of c14+refractor+ap900+ATS. If the moon is rising or clouds coming in and the observing window is two or three hours I might go for c8 on Berlebach and G11. If it's neighborhood viewing for short periods a 3.6 or 5 inch apo on dm6 and tpod. I'm fortunate to have a lot of toys and can tailor the configurations to the circumstances.

Edited by gnowellsct, 13 April 2019 - 08:41 AM.


#36 Axunator

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Posted 13 April 2019 - 08:56 AM

I've used a Berlebach Planet regularly since 2007 but this view about the primacy of wood is over simplified. The Losmandy hd is aluminum and as solid or more so. The Tpod 110 is aluminum and as solid or more so. (The HAL vixens are well reputed but I haven't owned one.) The ATS pier is aluminum and also as solid as the Berlebach. I own that too. 10micron also has a superb aluminum tripod which I saw at NEAF but I don't own.

The reason to go with wood is that in freezing weather you don't have brutal skin contact problems. Even so I chose the Tpod for the dm6 because it is lighter and faster set up.

I agree with requiring zero damping time for performance. I use my tripods with g11, Dm6, and ap900. The ap900 is excellent on losmandy HD and ATS.

A bouncing scope makes focusing difficult. The whole reason we're out there is to get the object in focus. And it interferes with observing too.

Anyhow berlebach is a competitive and attractive top tier tripod but aluminum alternatives are too. Stability lies in design and execution.

I use my scopes two at a time and solo. I don't always go for the 45 minute setup of c14+refractor+ap900+ATS. If the moon is rising or clouds coming in and the observing window is two or three hours I might go for c8 on Berlebach and G11. If it's neighborhood viewing for short periods a 3.6 or 5 inch apo on dm6 and tpod. I'm fortunate to have a lot of toys and can tailor the configurations to the circumstances.

Greg, I believe you are on the right track saying that wood as a material doesn’t have any magical properties that couldn’t be achieved with other materials. However, it does not mean that
1) wood as a material would not have very good vibration dampening characteristics, and
2) those cheap, round steel tube tripods would not ring like a bell once excited with a suitable resonant frequency.

Case in point: Berlebach Report is a really light-weight tripod, and is downright flimsy in design. Yet, it is vastly more vibration-resistant than a much heavier 1.75” Synta steel tripod, once either one is loaded with a bit longer refractor. I know, because I’ve done the experiment many times myself. Design or the material? I do not know but vote for the latter shrug.gif

But now we digress and wander off-topic...

EDIT: come to think of it, the legs of Vixen HALs (on which I don’t have any experience either) are very similar in design to Berlebachs, despite having been made of aluminum. The truth might lie somewhere in between...

Edited by Axunator, 13 April 2019 - 09:14 AM.


#37 Tyson M

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Posted 13 April 2019 - 12:27 PM

Yes you are crazy but you're in good company.

 

DON'T sell the DF, but the 9.25 on the other hand......a Mewlon 210 may be just what you need. 


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#38 macdonjh

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Posted 13 April 2019 - 01:00 PM

Yes, you're nuts. I get by just fine with this little guy in really dark skies. 

 

That'll be a $300 diagnosis fee please.

 

- Cal

There are no dark skies in the Bay Area.  lol.gif 

 

I could think of swapping my C9.25 to M210, but I wouldn’t be using it at home any more I currently use my C9.25 for the very reasons stated above. Just too large. The best scope is the one you use most often, even if the bigger one offered better views.

And compared to a 6” f/12, one can hold the 4” f/7.4 doublet Tak between one’s fingers like a pencil - I can imagine how a large, long-tube frac can become a chore to setup, no matter how great the views... The compactness of Cassegrains is a major part of their attractiveness, but wide fields provided by small APOs is a major part of theirs. I cannot think of my life as an amateur astronomer completely without one anymore. Of course, it all depends on one’s interests and preferences.

Looks like I wrote too much.  The point I wanted to make is that I prefer the compactness of a Cassegrain over the obstructionless view afforded by a refractor.  However, you've already stated later in the thread that you like your refractor for the wide field views, so an M180 will not replace your refractor.  I think you'll like the freakishly sharp views the Mewlon gives and the extra aperture will be addictive for lunar and planetary viewing.  

 

I need someone to come here and tell me that the difference in views between the 4” APO and M180 is nil, otherwise I’m doomed.

Nope, can't do it.  I think you'll like having both.  It also seems like you've already decided...  lol.gif 


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#39 Cali

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Posted 13 April 2019 - 01:24 PM

There are no dark skies in the Bay Area.  lol.gif

 

 

Actually there is. See the Del Valle Regional Park just south of Livermore. (Del Valle observing site)  The Tri-Valley Stargazers Astronomy Club has many activities in the East Bay.

 

- Cal


Edited by Cali, 13 April 2019 - 01:31 PM.


#40 macdonjh

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Posted 13 April 2019 - 06:31 PM

Actually there is. See the Del Valle Regional Park just south of Livermore. (Del Valle observing site)  The Tri-Valley Stargazers Astronomy Club has many activities in the East Bay.

 

- Cal

I had no idea, but then I grew up in the center of San Jose's white zone.



#41 luxo II

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Posted 13 April 2019 - 07:45 PM

Axunator - having used both an Intes M715D is better than a the Mewlon 180 - the Intes has no vanes, and a smaller CO.

The Tak is for wide field stuff which the Mewlon is not the scope for. But on moon and planets the Mewlon is the better pick - provided you don’t mind diffraction spikes. If you really don’t like diffraction spikes then buy a mak, .

The second thing is aperture counts, always, and in this respect a lot of DSOs will be simply out of reach of the Tak that are easy in a 7” or 9”. In particular galaxies.

I just don’t see why you would use a smaller scope when you have a larger one that will outperform it.

Edited by luxo II, 13 April 2019 - 07:52 PM.


#42 Astrojedi

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Posted 14 April 2019 - 09:45 AM

Mounting requirements for visual is a hugely individual and subjective thing. I know I’m at the end of Gaussian curve at CN who tends to overmount for visual. Most people here talk like it’s normal to have the scope shaking for 2 seconds after touching the focuser. I don’t get it at all. Kills the enjoyment of observing for me if the image jumps around for two seconds every time I touch the scope or there’s a lightest breeze.
 

 

Agree... but let me add... the C9.25 is rock solid on my AVX with vibration suppression pads. No vibrations even when focusing... just saying. Same on my M2C Mount when used on CGEM tripod.

 

No need to justify... Just get the Mewlon... : )


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#43 Astrojedi

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Posted 14 April 2019 - 09:56 AM

Couldn't agree more, my Mewlon will ride on the AZ-EQ6GT on a Tak EM400 tripod, there is no shaking even when focusing ..... but the tripod does have a 450Kg load capacity !!!! grin.gif

 

This is a very important point. Many folks confuse mount capacity with using insufficient tripods. For example when I had my AVX on a concrete pier even the C11 was rock solid - no vibrations with tapping or focusing.

 

I have more tripods than mounts. When I use the larger OTAs I typically change the tripod.


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#44 sedmondson

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Posted 14 April 2019 - 11:21 AM

I have a 4" Traveler and a Mewlon 180. I use them on a DM-4, and I think the M180 should work well on your small mount also. But you may need a handle to help pan the sky because you don't have much leverage with the short tube of the Mewlon.

 

I much preferred the M180 over the 4" apo in my suburban backyard, and you probably will also. So go for it. When you go to a dark site, take your 4" apo and 9.25" SCT and leave the Mewlon at home.

 

Regarding cool down; if your apartment has a balcony or patio, you could set the scope outside for awhile before taking it down to your shared yard. Alternatively, you could mount a small fan to the inside back plate, which (although may not shorten cooling time much) will definitely decrease tube currents. I did this to mine.


Edited by sedmondson, 14 April 2019 - 11:22 AM.

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#45 Axunator

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Posted 14 April 2019 - 07:46 PM

Agree... but let me add... the C9.25 is rock solid on my AVX with vibration suppression pads. No vibrations even when focusing... just saying. Same on my M2C Mount when used on CGEM tripod.

No need to justify... Just get the Mewlon... : )

This is a very important point. Many folks confuse mount capacity with using insufficient tripods. For example when I had my AVX on a concrete pier even the C11 was rock solid - no vibrations with tapping or focusing.

I have more tripods than mounts. When I use the larger OTAs I typically change the tripod.

I agree. The weakest point of affordable, generic mounts is usually the tripod (I’m speaking of visual use, where solidity and freedom from handling-induced vibrations is vastly more important than sub-arcsecond tracking accuracy). Fortunately, good third-party upgrades are nowadays easily available. Of course, they increase the cost of the mount by several hundreds €/$, so I fully understand that if one’s on a tight budget it feels hard to justify the expense.

Agree on anti-vibration pads as well. If I have to undermount (e.g. for logistic reasons while traveling), anti-vibration pads actually do help in fighting vibrations. Sorbothane is quite a magical material... cool.gif

Edited by Axunator, 14 April 2019 - 09:49 PM.


#46 Axunator

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Posted 14 April 2019 - 07:54 PM

I have a 4" Traveler and a Mewlon 180. I use them on a DM-4, and I think the M180 should work well on your small mount also. But you may need a handle to help pan the sky because you don't have much leverage with the short tube of the Mewlon.

 

I much preferred the M180 over the 4" apo in my suburban backyard, and you probably will also. So go for it. When you go to a dark site, take your 4" apo and 9.25" SCT and leave the Mewlon at home.

 

Regarding cool down; if your apartment has a balcony or patio, you could set the scope outside for awhile before taking it down to your shared yard. Alternatively, you could mount a small fan to the inside back plate, which (although may not shorten cooling time much) will definitely decrease tube currents. I did this to mine.

Thanks for encouraging feedback Steve! I actually can put the scope outside before observing to cool down, if I stay  at home to keep an eye on it.



#47 Traveler

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Posted 14 April 2019 - 11:15 PM

How about collimating a Mewlon? Read some topics about collimating a Mewlon and it looks not a very easy task.



#48 Axunator

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Posted 15 April 2019 - 12:22 AM

How about collimating a Mewlon? Read some topics about collimating a Mewlon and it looks not a very easy task.

I love challenges grin.gif


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#49 TxStars

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Posted 15 April 2019 - 12:23 AM

How about collimating a Mewlon? Read some topics about collimating a Mewlon and it looks not a very easy task.

I'm sure if the OP can collimate their C9.25 they can easily collimate the Mewlon.


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#50 Astrojedi

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Posted 15 April 2019 - 06:52 PM

I'm sure if the OP can collimate their C9.25 they can easily collimate the Mewlon.

Collimating the C9.25 is quite a bit easier than a Mewlon but I don't think this is a relevant factor for the decision as op's scope choice seems to be driven by other factors.




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