Takahashi Mewlon-210 f/11.5 Dall Kirkham Reflecting OTA Telescope
Takahashi Mewlon-210 f/11.5 Dall Kirkham Reflecting OTA Telescope
The Mewlon Series of Dall-Kirkham Telescopes by Takahashi combines refractor-like performance in a larger folded optic reflector design. The standard EM-200 or optional NJP mounts provide a stable, accurate platform for the M-210. The integral polar alignment telescope and R.A. axis level make accurate polar alignment to within 2 arc minutes of the celestial pole quick and easy. The reticle is designed to be used in either Hemisphere until the year 2030. No other manufacturer uses such a highly accurate polar telescope. The Mewlon series of Dall-Kirkham Cassegrain telescopes from Takahashi offer the experienced observer a level of performance and portability not found in other Cassegrain telescopes mass produced for amateurs. The classical Cassegrain telescope offers excellent performance, but they are extremely expensive to produce at large apertures. By concentrating on the Dall-Kirkham Cassegrains, the Mewlon telescope offers a professional level of performance within reach of most amateurs.
The Takahashi Mewlon employs an ellipsoidal figure on the primary mirror and a spherical figure on the secondary. By focusing on very tight tolerances for these surfaces, Takahashi is able to deliver a compact telescope with reasonable aperture and high resolution. Where fast F/ratios are not required, the F/12 Mewlons provide excellent contrast by utilizing a smaller secondary mirror than comparable Cassegrain designs. Secondary obstruction as a percentage of diameter is 29-31% on the Mewlons. Classical Cassegrain telescopes usually have secondary obstruction of 32% or greater. Commercial Schmidt-Cassegrains have secondary obstructions of approximately 38% for F/10 systems. Ritchey-Chretien Cassegrains have even more secondary obstruction making them less suitable for visual, high contrast applications.
Takahashi uses extensive knife-edge baffling to minimize stray reflections as well as a specially designed tube that also acts as a light baffle. The result is an instrument that rivals an excellent long-focus Newtonian or refractor for contrast and sharpness. Some opticians have criticized the Dall-Kirkham design as having unacceptable coma. With most eyepieces (including Panoptics and Naglers) the coma is negligible and well outside the field of view. Stars are much smaller and sharper than in commercial Schmidt-Cassegrains. Coma may be a problem for wide-field astro-imaging, but these instruments were not designed for such tasks. With Takahashi's field flattener/reducer, these instruments offer superb off-axis images at F/9.
Takahashi produces precision optical surfaces capable of delivering an airy disc of 20. Because the Mewlon primary mirror is larger than the effective aperture, its cell installation engineering helps to eliminate mirror stress which can cause astigmatism. The focuser mechanism has also been carefully designed to reduce shifting and maintain consistency. Both the Mewlon 250mm and 300mm models come standard a secondary mirror translating focuser that's accomplished with the electronic hand controller. With a wide range of both visual and photographic accessories available to the Takahashi Mewlon series, there is no reason why you shouldn't be able to achieve any astronomy project you have in mind using this fine telescope.
The 250mm and 300mm Takahashi Mewlon electronic focusing is accomplished by moving the secondary mirror. This eliminates the image-shift problem inherent to commercial Schmidt-Cassegrains with moving primary mirrors. Because of the loose tolerances required in moving large and heavy mirrors on a baffle tube, most SCT's will not maintain perfect collimation. Image quality is then compromised in such optical systems. The large Mewlons also have removable covers for their primary mirror cells, this facilitates rapid mirror cooling so that the observer can take advantage of favorable seeing conditions more quickly. These features make the large Mewlons ideal for high-resolution CCD imagery.
With the Mewlon series, it isn't necessary to sacrifice optical performance for ease of use and portability. When it comes time to place your Takahashi Mewlon telescope on a mount, it's as easy as simply connecting the dovetail plates. The high quality finderscope not only lends itself to the packages as an excellent instrument for alignment, but is also designed as a convenient "grab handle" to assist in mounting and transport. It's rigid construction means help in handling the optical tube without fear of bending or breaking. On larger models, the Mewlon also includes a counterweight against the body to help balance the optical tube. Just these small considerations in Takahashi's Mewlon design mean quality in engineering that sets it apart.
The 8.3" Mewlon 210 weighs just 18lbs (8.2kg) with a 7x50 finder attached. The Mewlon 250 weighs only 28lbs (12.7kg) and is remarkably compact for a 10" Cassegrain. Both of these instruments are highly portable and offer deep sky views that are exceptional. On the planets, many observers have reported seeing details they thought impossible with telescopes of this aperture. With the exception of a few diffraction spikes around bright stars, on might believe they were observing with a large apochromatic refractor. The advantage, though, is a greater amount of light grasp and resolution than a comparably priced refractor. Indeed, the Mewlons offer an exceptional value in their aperture class.
So if you desire a professional grade instrument in a compact, lightweight package or are tired of compromising light grasp for crisp detail and contrast, check out the Mewlon Cassegrains by Takahashi. You will be pleasantly surprised by their performance. For further analysis of the Takahashi Mewlon Series of Dall-Kirkham Cassegrains, please read Jean Dragesco's review in his book High Resolution Astrophotography, Cambridge University Press, 1995.
Takahashi Product Number: TLK2101
Important Note: Takahashi America requires that their telescope optical tube assemblies be shipped via 2nd Day Air or faster in order for the full warranty to be in force. Please make sure you choose the appropriate shipping method in your shopping cart or, if you speak to an OPT associate, request 2nd Day Air or faster. If you are purchasing a telescope and mount package or any accessories to accompany an OTA, please contact OPT for a shipping quote, since only the OTA is required to ship second day air but all other products can be shipped separately via any other available shipping method. Thank you!
|Aperture||210 mm (8.25")|
|Camera/Eyepiece Connection||2" nosepiece|
|Dawes Limit||0.55 arcseconds|
|Focal Length||2415 mm|
|Light Gathering Power||900x|
|Optical Design||Dall Kirkham|
|Tube Weight||17.9 lbs|
|Warranty||5 Year Warranty|
Sold my 127mm triplet for one of these 210mm Mewlon's and dont regret it for a heart beat ! .As good as my mates 7 inch APO easily , and a whole lot more managable , as they say Refractor like images from a Reflector , I wont be selling this beauty .
5 stars? Yep for me it is worth it. After a long queste in search of an allround telescope I got my eye on this beauty.As an FSQ106ED Owner I already was a fan of Takahashi .Here in the Netherlands wheather is terrible for Many nights of the year so on those few perfect nights when AP is not possible but planet photography is.It is the Perfect scope for captureing the fine detail on Jupiter and Saturn .On nights when you don,t feel like AP? Slide in your nagler or panoptic and Experience the refractor like star images.pinpoint. What about the coma? Yeah Sure it is there in my 35 mm panoptic when my eye is not straight behind the eyepiece.straigth your back and allign your position and you will see a very small amount of coma , does it botters me? Maybe only when I want to see the double cluster together. In my 20 mm nagler no coma to be found . Also no coma in the 13 and 9 mm. The moon with binoviewer is breathtaking . M13 to the core. Wat about AP? Well that,s my new adventure .the reducer is ordered and the coupling ring to reach the 56 mm backfocus distance of the reducer. Not an easy task but doable on 1960 mm f9. No widefields offcourse but planetary nebulas are my main goal. If your are looking for a high end telescope with enough aperture for deepsky viewing, planetary imaging , narrow field high res AP . Don,t look any further. The Mewlon 210 is the way to go. Clear Skies Frans Lalleman www.sterrenwacht-wave.nl
I just can’t say enough good things about this 8” version of a very good telescope design and great manufacturer of Astro gear. Yea I’m Hyped UP about this 8” scope, because once you spend enough nights using this Lil Treasure, the 210 won’t seem like a “Jr” anymore, they are simply a thrill to use and one scope you can't get enough of! Clear Skies, James Edwards Elk Grove CA