MaxBright® II Binoviewer at the Takahashi Mewlon

Takahashi is known for excellent telescopes, but when it comes to adapting accessories, they sometimes go their own way, which can make life hard for astronomers. In particular, the use of a bino viewer on the Takahashi Mewlon kept raising questions, and since we don't sell Takahashi telescopes, we couldn't simply try it out ourselves.

Thus, we are all the more grateful to our customer Maiko, who was able to successfully use the Baader MaxBright® II Binoviewer with case (#2456460 , € 479,-) with his Mewlon 180 C and gave us feedback on his setup. We thank him for the information and would like to briefly present the required parts here.

At the Mewlon 180 C, he used:

Takahashi Mewlon 180 C with MaxBright II Bino-Viewer

Of course, it is not just a matter of adapting the bino viewer mechanically, you also have to come into focus – on the Mewlon, the 1.25x glass path corrector is sufficient for this. Another advantage of a glass path corrector: it picks up the light beam "further back" in the telescope, where the beam of light is narrower, so that vignetting is avoided.

And how does it work under the night sky? Here, this combination fulfills the expectations, as the following observation report proves.

We thank Maiko for the information about the adaptation to the Mewlon and wish him many clear nights!

Observing with the Mewlon 180 C on the roof top. May 17th/18th 2023

Actually, yesterday would have been a much better night for the first deep sky session with the Mewlon 180 C: My SQM showed values of 21.2 to 21.3 MPSAS – and that on the roof top in the middle of a small town! The Milky Way was clearly visible and structured, which corresponded probably to a good Bortle 4 sky.

Well, I had to use the following night: The SQM showed 20.6 MPSAS, the Milky Way was barely structured, slightly blurred, probably between Bortle 4 and Bortle 5.

MaxBright® II Bino and Rigel Quickfinder at the Mewlon 180 C

For moon and planets, I tested the combination of HEQ 5, Mewlon 180 C and the Baader bino-setup, consisting of MaxBright II, BBHS T2 prism, 1.25 x GPC, ring dovetail and heavy-duty changer a few times. With the Panoptic 24mm and the Nagler 12mm T4, which were modified to 1.25", there were good to very good moments for observing the moon. During the brief moments of good seeing, the view is breathtaking. Unfortunately, I have been waiting in vain for good seeing (lasting longer than a few seconds) so far this year. Last August and September I had conditions that made for wonderful Jupiter and Saturn observations (at that time still monocular), also from the roof. Saturn appeared almost like in a photo at 240x in the 9mm Nagler, at about 20° height above the horizon. Several years before, I had a spectacular view of the moon with the Mewlon in April at 180x: contrast and sharpness were overwhelming, the image as if cut out... so I hoped that this spring the seeing would play along... well, maybe when the morning visibility of Saturn and Jupiter begins.

After setting up the telescope and finishing the polar alignment, I wanted to start with M3, but had no success. So I tried M13 and struggled, until finally I had it in the eyepiece. Why? Because of GoTo-refusal or purism...

To be able to use the setup binocular and without GoTo, I had to solve some problems. When pointing the telescope to a new object, the system must be in good balance, because the clamps are loosened. But this only works if the bino is always in the same position. I decided to align it to the axles of the mount. But this blocks the 30mm finder. I roughly locate the object in the Rigel finder I have attached. Then I clamp the axles. Now the bino can be carefully rotated into observation position. The Mewlon viewfinder can then be used for more precise adjustment, with corrections made via the motors.

This works fine for moon and planets, but I would not recommend this method for deep sky objects. Besides the usual observing problems, the limited visibility of the objects in the mewlon viewfinder and the necessary bending of your body to look into both finders cause lots of frustration when you have to guess in the Mewlon's viewfinder in which direction the invisible target has to be moved relative to the invisible crosshairs by the tracking motors which move only at snail's pace.
Ready to go: Monocular and binocular configuration

You're better of searching the objects monocularly with a long focal length 2" eyepiece, so that the object is in the field of view when switching to the bino-viewerrn.

Well, M13 was a delight in the binoviewer at about 110x: A quite dark sky background, and countless little stars in a cluster. At 220x the image naturally became quite dark.

M92 was a dream. I caught myself saying: "What a cute little bunch." On the same telescope, 220x was more usable, but not really good either. I mean, this magnification is better suited for the moon and planets in nights with really good seeing.

For a higher magnification in the bino-viewer, which is for medium seeing or brighter deep sky objects, I will probably try 16/17mm eyepieces, as 16mm will give you about 169x...There was something very touching about being able to enjoy M92 resolved into stars with both eyes almost meditatively on the roof garden of my small town at 3 o'clock in the morning.

The Mewlon is best known as a telescope for planets, but I encourage you to try bright, compact deep sky objects.

Monocularly, I had beautiful observations of M13, M92, M57 and the Eskimo Nebula in the Mewlon under a medium Bortle 4 sky.

Bino-viewers are also often praised for planetary and lunar observation.

Here, too, I recommend trying brighter deep-sky objects at the Mewlon. It can be very rewarding.

Since I am observing without GoTo, it is important for me to be able to quickly switch between the bino viewer and a 2" eyepiece to find objects more easily. I have now found a working combination for this too:

Mewlon 180 C on HEQ 5 in tracking-only mode monocular vs Baader Planetarium Maxbright II

It seems that my Mewlon setup is now ready to suit my observing style.

My equipment:

  • Mewlon 180 C upgraded with Rigel Quickfinder
  • ScopeStuff FineFocusKnob
  • mirror diagonal Televue Everbrite 2“
    • LVW 42mm, Nagler 22 T4, Nagler 12 T4 eyepieces
  • Baader Planetarium Maxbright II Bino-viewer, GPC 1,25 x, Zeiss Heavy Duty Quick Changer, T2-BBHS Prism
    • Panoptic 24mm eyepieces and Nagler12mm T4, modified for 1,25“

First night, June 11th, 2023, starting shortly after midnight:

My goal with the Mewlon was to find a solution to be able to quickly switch between mono and bino observations. On the one hand, I want to be able to observe optimally adapted to the conditions, on the other hand, I want to give fellow observers the option of going the "easier" way of monocular observation, and then to be able to observe effortlessly with a bino-viewer. In addition, I have developed the ambition to find objects in the classic way without a goto-mount with the setup described and to be able to observe either monocularly or binocularly.

The observation site is my small-town roof garden, which provided me several nights of very good seeing.

At dusk, I set up my telescope relaxed in a T-shirt – tt must have become summer... I used the Kochab method to polar-align the telescope. I used the the Celestron power tank as power source. My first object was M13. I found it quite easily with Rigelsucher and the LVW 42 eyepiece. Then I switched to the bino: M13 was beautiful to see for a short time, then fog moved in. The focus difference between mono ans bino is noticeable, but far from dramatic. In all configurations I reach focus effortlessly.

I paused, relaxed, looked a few times through the telescope. Eventually the fog cleared and I looked for M13 again. At 113x it was quite respectable in the 12mm Nagler. In about 30 minutes, the cluster remained reasonably in the centre of the field of view, which speaks for an acceptable polar-alignment.

M3 was a bit harder to find, but finally I succeded. Not very impressive at 113x and quite low in the sky...

On the other hand, M92 was a beauty: resolved into fine stars in the bino-viewer, again at 113x. It is wonderful to be able to experience this from the roof at home! Only a welcome-back-party of the neighbours distracted me a little.

After a break, I tried my luck at Saturn. Around 3:30 it was a little over 15° high above the horizon, of course still too low. But still it was quite pleasant at 113x, with a few quiet moments every now and then. Then I bravely tried the 12mm eyepieces at 225x. Surprisingly, there were quite passable phases despite the bad seeing. Cassini division, ring shadow, and colours of the cloud bands were well visible. I'll get back to Saturn when the conditions are better. Saturn was one reason to use a bino-viewer with the Mewlon. Oddly enough, at 225x it didn't seem that big to me.... if only the seeing was a bit more reliable...

All in all, it's a successful start. It's wonderful what is possible when using both eyes and combining Takahashi and Baader.

Every now and then I read about back-focus problems. I would like to encourage you to find out on your own Mewlon whether it is possible to successfully use a bino-viewer, and also use it for deep sky.

It seems to work very well for me.

Maiko

One thought on “MaxBright® II Binoviewer at the Takahashi Mewlon”

  • fedele

    i was the first to check this. You need anyway a GPC
    https://www.facebook.com/photo/?fbid=10223530626447891&set=pcb.10223530626727898

    There is another best solution, with less Back focus, that i show in this forums some time agò (nose in original visual back is not so good):
    https://www.cloudynights.com/.../697318-takahashi.../page-4

    Reply
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