4" Tak vs Mewlon 180c

[MalcolmM]

Calling all Tak enthusiasts

I think I have read just about everything I can find on the 180c in this and other forums and a very good article by Roger Vine. Most people seem to rate it very highly.

I am very very tempted with one (I would almost buy it based on looks alone!) but I would love to hear from people who have used both and can give me a comparison based on real practical experience, not a theoretical comparison.

I think I understand the shortcomings of the 180c. I am not considering other makes, I am not considering a 210 or a 250.

I have an FC100DC so....

In your opinion, would the 180c provide a big enough step up in lunar/planetary/small DSO views in UK Bortle 4/5 skies to warrant the expense of buying one?

I would envisage dual mounting it with the 100DC, and it would be for visual use only.

Many Thanks,

Malcolm

Edited January 21, 2022 by MalcolmM

[dweller25]

Hello Malcolm,

I have the 4” Tak FC100-DZ and the Mewlon 180c and have compared them on DSO’s, planets and the Moon.

I can tell you that the views through the 180c beat the 4” refractor in all areas ie resolution, planetary detail and brightness. I suspect it will be very close to the performance of a TSA120.

Contrast is the same in both scopes - very, very good.

I am very surprised by just how good the views in the Mewlon are - and I am a refractor guy 😱

Plus it’s easy to mount - mine is on a Vixen GP and it’s very comfortable to use.

I have put a RACI finder on mine as I found the straight through finder very uncomfortable to use - but I have a bad back !

There is slight image shift during focusing.

Cool down - it needs active cooling - I made one of the these - see below - and rest it on the front of the spider - it takes about 40 minutes to cool the primary. Once cooled it’s just like looking through a refractor with really tight stars.

I have tried 3xSCT’s, 6xMaks and a Classical Cassegrain which never gave me the wow factor but this Mewlon is so sharp and contrasty it’s amazing.

The two scopes compliment each other well - The 4” is a quick cool down grab and go for very low or high power, the Mewlon is more suited to high power - mine starts at x83 with the eyepieces I have but can go to higher mags than the 4” (seeing permitting) and still have a reasonably bright image.

The Moon through the Mewlon is super sharp.

Hope that answers your question 🙂

Edited January 21, 2022 by dweller25

[MalcolmM]

Thanks @dweller25, that's very interesting and exactly the sort of information I am looking for.

It sounds like a wonderful scope.

I started laying the groundwork with my partner last night on a romantic moonlit walk on the beach  I told her it was a beautiful  thing, I'm not sure she knew what I was talking about!

I had read that they can take a bit of time to cool but I thought that with the open tube and not too extreme UK temperatures it would not be too bad, so I'm very interested to hear you needed active cooling for 40 minutes.

Thanks again,

Malcolm

 

[dweller25]

It’s often said that open fronted scopes cool down “quicker” but I have found that it’s not much quicker 🙁

The big advantage of the open tube which I forget to mention is NO DEW 😀😀😀

In reality the 20mm thick mirror holds onto it’s temperature deep in the tube very well so some type of active cooling is essential. Blowing air into the primary helps to remove the boundary layer of warm air that stays on the mirror surface, also there is a good 20mm air gap behind the primary to aid air flow and cooling. No problems with dust on the primary so far but the back is easy to take off for mirror cleaning as per the Tak instruction manual.

If i were brave I would drill two holes in the back of the OTA and install two small fans blowing onto the back of the mirror, but I am not that brave 🤷🏻

[MalcolmM]

Take a drill to a Tak? Shock horror! I certainly would not be that brave

What you say sounds sensible to me. If you want to cool a cup of tea you blow on it  

Thanks again,

Malcolm

 

 

[Cleetus]

On 21/01/2022 at 08:55, MalcolmM said:

Calling all Tak enthusiasts

I think I have read just about everything I can find on the 180c in this and other forums and a very good article by Roger Vine. Most people seem to rate it very highly.

I am very very tempted with one (I would almost buy it based on looks alone!) but I would love to hear from people who have used both and can give me a comparison based on real practical experience, not a theoretical comparison.

I think I understand the shortcomings of the 180c. I am not considering other makes, I am not considering a 210 or a 250.

I have an FC100DC so....

In your opinion, would the 180c provide a big enough step up in lunar/planetary/small DSO views in UK Bortle 4/5 skies to warrant the expense of buying one?

I would envisage dual mounting it with the 100DC, and it would be for visual use only.

Many Thanks,

Malcolm

Your plans are very similar to mine - already own 4 inch Tak and am seriously thinking about a Mewlon - but I am considering a 210 rather than the 180. I will be downsizing from a 12 inch SCT and going all the way down to the 180 might be a bit of a shock for me. That's my justification for preferring the 210.

Was planning on mounting it on a Vixen SXP2 with the option of mounting the two Taks side by side if I ever felt the need. Anyway, have you been given any idea of the delivery time for the Mewlon?

[MalcolmM]

1 hour ago, Cleetus said:

Anyway, have you been given any idea of the delivery time for the Mewlon?

No, I haven't I'm afraid. FLO says 7 to 10 days on their website. I am still wavering, it being yet another big outlay! But it does look fabulous I currently use a 100DC with a 60CB side by side and would love the option of the 4" with the 180.

Malcolm

[Cleetus]

1 hour ago, MalcolmM said:

No, I haven't I'm afraid. FLO says 7 to 10 days on their website. I am still wavering, it being yet another big outlay! But it does look fabulous I currently use a 100DC with a 60CB side by side and would love the option of the 4" with the 180.

Malcolm

Okay, wasn't sure if there was a long waiting time for these. My plans are on hold at the moment as I will be moving house this year but once that's done I'll make my move. Will be interested in your comments/first light. Have yet to hear a bad thing about these Mewlons, apart from the cool down issues.

[HollyHound]

I also have the FC-100DZ and Mewlon 180C, both fantastic scopes and they complement each other very well… I have started dual mounting them on the AZ100.

For a recent comparison, check out this session report from last week (copied the text here, as the link doesn’t seem to work)…

Quote

Fog cleared here almost as soon as it got dark, so I've had a most enjoyable two hours, almost exclusively looking at the moon, with a tiny diversion onto M42 and Rigel.

This is the first time I've had the FC-100DZ and Mewlon 180C together, and also I've moved the AZ100 onto the iOptron Tri Pier (so freeing the Uni 28 for the Vixen GP which I haven't yet used very much!). This combination is absolutely rock solid, even pressing my eye fully onto eyepieces and focussing or moving the slow motion controls... barely registers any adverse movement on the scopes 👍

Was comparing the moon between the two scopes and of course the DZ cooled much more quickly, to give lovely sharp, contrasty and white views (zero colour anywhere except from the atmosphere on low down stars). Mewlon took well over an hour before the "boiling" view settled (I think actually it's still cooling even now). Pentax XWs in both scopes... XW14 to 3.5 for the DZ and the Mewlon is equipped with a pair of XW20s in the binoviewer.

Just a joy, the longest I've spent just cruising around on the moon, just stopping at objects of interest and comparing the views... I'd have to say there's not a lot in it really, but there's a tiny bit more detail on the Mewlon, which could due to the super relaxed view through the XWs on the binoviewer (need to check this on the DZ sometime). I even popped the Vuxen HR 2.0 and 1.6 (their first light) and gobsmacked how much detail is still coming through on the DZ... this is a seriously impressive lunar scope 😀

Checked out Rigel and even though still a bit low and not ideal conditions perhaps, the DZ split it easily with an XW7 (I think 🤔), although there was some colour visible (low and atmosphere).

Had a quick look at M42... Trapezium lovely in both, some nebulosity visible in the DZ (but hampered by the moon) and this is where the Mewlon shone through, showing plenty of nebulosity (even without averted vision). Surprisingly I'm really enjoying the binoviewer for this kind of viewing too, so just left that on the Mewlon throughout.

Finally my fingers where starting to go quite numb (note to self to locate suitable gloves for observing) so have popped back indoors to warm up and have some food... planning to pop out a bit later and do a little more, but really happy to get these two scopes out together and finally have a really really good go on the moon 😄

 

Edited January 22, 2022 by HollyHound

[MalcolmM]

Thanks @HollyHound, I had actually read your report before, but enjoyed reading it again. I'm finding it very difficult to come up with a reason for not getting one

Your dual setup looks great!

Malcolm

[Cleetus]

On 22/01/2022 at 22:36, MalcolmM said:

Thanks @HollyHound, I had actually read your report before, but enjoyed reading it again. I'm finding it very difficult to come up with a reason for not getting one

Your dual setup looks great!

Malcolm

Is there any particular reason why you would go for the Tak rather than, say, an 8" Edge HD? More aperture for similar price.

[Fedele]

49 minutes ago, Cleetus said:

Is there any particular reason why you would go for the Tak rather than, say, an 8" Edge HD? More aperture for similar price.

Because no comparison is possible.

I had a C8HD water heater for three months .... it was the most useless three months of my life.

Edited January 24, 2022 by Fedele

[Stu]

Does the Mewlon 180 have an over sized primary like the 210 (which has a 220mm primary)?

[MalcolmM]

1 hour ago, Cleetus said:

Is there any particular reason why you would go for the Tak rather than, say, an 8" Edge HD? More aperture for similar price.

I have to admit to a severe case of Takitis!

So it's a Tak or nothing!

And I know that is not exactly rational thinking but I have hugely enjoyed not only using my Takahashi scopes but also owning them

A number of people have commented on the Mewlon giving very 'refractor' like views and as a refractor man I like the sound of this  

@Stu Roger Vine says in his review he thinks Tak use an oversize mirror in the section about lack of distortion at the field edge. To quote "I believe Tak may use an outsized mirror to help"

 

I'm convinced now the Mewlon will give me great views, I'm just a little concerned that I'll have very few nights where conditions will allow it to out-perform the 100DC. And the cool down time bothers me a bit as many of my observing sessions only last an hour or so, so I would need more preparation for my sessions than I currently allow!

So no decisions yet!

Thanks for all your interest,

Malcolm

[dweller25]

3 hours ago, Stu said:

Does the Mewlon 180 have an over sized primary like the 210 (which has a 220mm primary)?

Yes

circumference = 610mm approx

diameter = 195mm

Edited January 24, 2022 by dweller25

[Stu]

1 hour ago, dweller25 said:

Yes

circumference = 610mm approx

diameter = 195mm

Thanks. That’s mirror circumference I assume, not OTA? Sorry for the daft question!

[Stu]

3 hours ago, MalcolmM said:

I have to admit to a severe case of Takitis!

So it's a Tak or nothing!

And I know that is not exactly rational thinking but I have hugely enjoyed not only using my Takahashi scopes but also owning them

A number of people have commented on the Mewlon giving very 'refractor' like views and as a refractor man I like the sound of this  

@Stu Roger Vine says in his review he thinks Tak use an oversize mirror in the section about lack of distortion at the field edge. To quote "I believe Tak may use an outsized mirror to help"

 

I'm convinced now the Mewlon will give me great views, I'm just a little concerned that I'll have very few nights where conditions will allow it to out-perform the 100DC. And the cool down time bothers me a bit as many of my observing sessions only last an hour or so, so I would need more preparation for my sessions than I currently allow!

So no decisions yet!

Thanks for all your interest,

Malcolm

Thanks Malcolm. Makes sense given they definitely use an oversized primary on the 210. I did find cool-down an issue on the 210, took a surprisingly long time. The suggestion of a watertight storage box to place it outside long before needing it seems a good ideal. The 180 should obviously also cool more quickly. I also like the three vane spider. Strangely I found the six diffraction spikes this gives (on my Heritage 150p) to be less intrusive that four bigger ones.

[Cleetus]

3 hours ago, MalcolmM said:

I have to admit to a severe case of Takitis!

So it's a Tak or nothing!

And I know that is not exactly rational thinking but I have hugely enjoyed not only using my Takahashi scopes but also owning them

A number of people have commented on the Mewlon giving very 'refractor' like views and as a refractor man I like the sound of this  

@Stu Roger Vine says in his review he thinks Tak use an oversize mirror in the section about lack of distortion at the field edge. To quote "I believe Tak may use an outsized mirror to help"

 

I'm convinced now the Mewlon will give me great views, I'm just a little concerned that I'll have very few nights where conditions will allow it to out-perform the 100DC. And the cool down time bothers me a bit as many of my observing sessions only last an hour or so, so I would need more preparation for my sessions than I currently allow!

So no decisions yet!

Thanks for all your interest,

Malcolm

Totally understand your reasoning. I'm thinking along similar lines. Also, I have owned an MCT, SCT, refractor, and newtonian so the DK design would be a new experience for me and judging by build quality alone the Tak refractor wins easily over the others. Not needing a dew strap for the Mewlon might be a small thing to some but I'm also attracted by one less cable waiting to be snagged or dew shield colliding with obsy roof. Keep it simple is my motto.

[dweller25]

30 minutes ago, Stu said:

Thanks. That’s mirror circumference I assume, not OTA? Sorry for the daft question!

Yes, mirror dimensions

The OTA diameter is 210mm approx.

[MalcolmM]

24 minutes ago, Cleetus said:

Not needing a dew strap for the Mewlon might be a small thing to some

Before I was introduced to Takahashi (thanks to many on this forum) I was considering a C6 but the thought of dew straps and/or shields ruining the look of the scope let alone the need for power or doubling the length of an otherwise short OTA ... I'm with you

Malcolm

[MalcolmM]

55 minutes ago, Stu said:

The suggestion of a watertight storage box to place it outside long before needing it

Yip, that sounds like a good idea thanks!

[HollyHound]

4 hours ago, MalcolmM said:

I'm convinced now the Mewlon will give me great views, I'm just a little concerned that I'll have very few nights where conditions will allow it to out-perform the 100DC. And the cool down time bothers me a bit as many of my observing sessions only last an hour or so, so I would need more preparation for my sessions than I currently allow!

Even though it's an open tube design, mine does still take a good while to cool down sufficiently before it starts to outperform my FC-100DZ... however, even after 30/40mins, the extra aperture is still very useful and usable for DSOs. Once it's fully cooled however then it really does outperform the DZ for sure 👍

This is one of the reasons why I'm setting up a dual mount solution for my longer sessions, so I can get started with the DZ after 15/20mins maximum and let the Mewlon keep cooling. I suppose it would be possible to pop it out sooner and just leave it so that it's already cooled when I come out to observe.

[HollyHound]

58 minutes ago, Stu said:

Strangely I found the six diffraction spikes this gives (on my Heritage 150p) to be less intrusive that four bigger ones.

Same here, much better compared to either my Dob or the CC I owned last year 👍

 

6 hours ago, Cleetus said:

Is there any particular reason why you would go for the Tak rather than, say, an 8" Edge HD? More aperture for similar price.

The Mewlon just doesn't dew up... at all... after four hours in my last session, the mirror was still clear whereas my Mak127 or C5 would have been dewed up for sure. Of course dew heaters would perhaps prevent it, but then it's more "clutter" for a visual session. One of the reasons I like my iOptron AZ Mount Pro is that it runs without power source or cables.

[MalcolmM]

52 minutes ago, HollyHound said:

iOptron AZ Mount Pro is

That's the mount I would (will ) be pairing them on

Malcolm

[Cleetus]

On 22/01/2022 at 22:23, HollyHound said:

I also have the FC-100DZ and Mewlon 180C, both fantastic scopes and they complement each other very well… I have started dual mounting them on the AZ100.

For a recent comparison, check out this session report from last week (copied the text here, as the link doesn’t seem to work)…

 

What are your thoughts on star shapes using the Mewlon compared to the DZ? With the Mewlon how near to the edge of the field of view can you get before distortion is noticeable? Is the following quote from a review consistent with your observations?

"I am surprised that stars don’t distort that much at the field edge, despite the DK’s reputation for off-axis aberrations. Stars remain points until 70-80% field width and even after that just become mildly comatic".