Review – Takahashi FS-60CB

Takahashi FS-60CB

The Takahashi FS-60CB is a fluorite doublet apochromat refractor.

Specifications

Aperture:  2.4 in. [60mm]
Focal Length:  14.0 in. [355mm]
Focal Ratio @ Prime Focus:  f/5.9
Prime Focus Photographic Field:  5.0°
Focal Ratio w/Reducer:  f/4.4
Photographic Field w/Reducer:  7.0°
Limiting Magnitude:  ~ 10.9 urban / ~ 12.1 rural
Resolving Power:  2.2 arc seconds
Tube Diameter:  3.1 in. [80mm]
Tube Length:  14 in. [359mm]
Weight:  2.2 lb. [1.3 kg]

FOV and Magnification

TeleVue 31mm Nagler 5:  6.7° @ 11x
TeleVue 22mm Nagler 4:  5.0° @ 16x
TeleVue 17mm Nagler 4:  3.9° @ 21x
TeleVue 12mm Nagler 4:  2.8° @ 30x
TeleVue 09mm Nagler 6:  2.0° @ 39x
TeleVue 1.25 Barlow 2x :  1.0° @ 79x

Introduction

For a while now I’ve been reevaluating my Takahashi FCT-76, trying to figure out what niche it fills in my observing life. As it turns out the answer is quite simple: wide-field viewing.  Now that may not seem like a revelation to you, but to the owner of this fine telescope it definitely was.  Why?  My guess is that I’ve been a strong adherent of apomania – those who subscribe to the claim that the end all of telescope design is the modern apochromatic refractor.

Okay, that may be a bit of a stretch but there’s also some truth to it.  It’s hard to deny that a small apo refractor provides beautiful panoramic views, and that the color correction is top-notch, but what about seeing objects brightly besides the Moon and planets?  This question can partly be answered in the context of where one observes from; in other words, your location greatly dictates your perception of the quality and utility of the optical instruments you own.

My thoughts on improving observing sessions now revolves around owning at least two or three telescopes instead of one:  A mid-to-large sized deep-sky scope and a small wide-field scope.  The mid-to-large sized deep-sky scope will either be a TEC 8″ f/3.5 Mak-Newt or a SkyVision 14.5″ f/4 Dobsonian, and the small wide-field scope will be the Takahashi FS-60CB.  A third telescope possibility would be the FSQ-85ED for quick and easy set-up, observing, and breakdown.

I bought the FS-60CB to achieve the widest of wide-field apo views that the FCT-76 couldn’t.

Design

Takahashi and its North American importer Texas Nautical Repair Company have created a very versatile refractor.  On its own, the FS-60CB would be fine instrument with only the standard 1.25″ visual accessories; but with the addition of upgradeable products offered by TNR, the scope’s overall performance is greatly enhanced – the most profound improvement being the ability to use 2″ eyepieces.  The Takahashi 2″ Ocular Adapter allows 2″ eyepieces and diagonals to be attached to the FS-60CB.  With a TeleVue 31mm Nagler Type 5 [which produces over 6.7° @ 11x magnification] “wide-field surfing” is truly amazing.

Are there any design drawbacks?  It’s really hard to find fault with the FS-60CB, especially when you consider the specific purpose and limited utility of owning one.  This is not a multifaceted telescope.  If you buy it, you do so for a particular reason:  wide-field and solar observing or as a guidescope.

Photography

CCD photography can be done when using the FS-60CB’s dedicated photographic reducer, delivering a flat 7.0° field at a fast f/4.4.

Photographic accessories for CCD astro-cameras are available through Takahashi and TNR.

Observing

Having used this telescope for several years, I’m very impressed with the views so far.  It looks like the collimation was a little better on the FS-60CB than my FCT-76, so I had the FCT-76 sent to TNR for servicing [including a lens cleaning – it doesn’t hurt to have a professional look over your telescope now and then].  The color correction is good for a doublet and much better than a TeleVue Pronto. But since this is a wide-field scope, there isn’t much need for perfect correction on bright stars.

Wide-field views of Mel 111 [Coma Berenices Star Cluster] and M 44 through the 31mm Nagler 5 were great.  The outermost stars in Mel 111 are almost completely taken in, and M 44 is surrounded by the star triangle of Delta, Gamma, and Eta Cancri with a lot of fov to spare.  All 4 stars of the stinger in Scorpius were seen in the same field [M 6 / M 7 and M 10 / M 12 combos as well].  Under the dark skies of West Texas, the wide-field sweeps of the Summer Milky Way were phenominal. Outstanding!

Alternatives

I can’t think of another comparable high quality telescope of similar aperture that can do what the FS-60CB does: provide excellent color correction, offer 2″ ultra wide-field views, along with incredible compactness for travel.  In my opinion, this is the ultimate wide-field finderscope.

Priced ~ $860 each.

7 responses to “Review – Takahashi FS-60CB

  1. Nice write-up, thanks. Have you looked at the 1.7x Extender-Q module that converts the FS-60CB into the FS-60Q model by any chance?

    • Dave, I haven’t yet. But speaking to the people at Takahashi America, it will do a great job of increasing the focal length for either visual or photographic use. The optics on the extenders are also very nice.

    • Vaidya, the FS-60CB doesn’t require a viewfinder because of its short focal length. I would recommend using the magnifications listed on the review page as a guide for what fov a low power eyepiece will provide. In my opinion, the minimum useful magnification for a viewfinder is about 7-8x.

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