David H. Levy Comet Hunter 6" f/4.8 Maksutov-Newtonian

by Explore Scientific Print

What would you like to print?
(Reviews and Documents/Videos will not be printed)

Basic Product Information
Full Description
Tech Details
Supplied Accessories
Recommended Accessories

More product information
  • This Explore Scientific ES152MN Mak-Newt reflector has:

    152mm (6") f/4.8 rich field Maksutov-Newtonian optics
    • dual-speed 2” Crayford focuser with 1.25" adapter
    carbon fiber body and dewshield
    • dual tube rings with Vixen-style dovetail and carry handle
    • extended product lifetime warranty

    There are few greater discoveries than the one you make the first time you look through a telescope and see another world. It is a moment that can turn mere curiosity into a life-long exploration of the heavens.

    That unique moment of discovery is why comet discoverer David H. Levy and Explore Scientific have designed a special edition telescope called the Comet Hunter. Its task is to help support the Sharing the Sky Foundation, a non-profit organization founded by Levy. The Sharing the Sky Foundation mission is to inspire people with the magic and beauty of the night sky.

    David H. Levy is the co-discoverer of Comet Shoemaker-Levy, whose multiple impacts on Jupiter in July 1994 produced the largest explosions ever seen by man. Just one of them (the G fragment) was estimated as being the equivalent of the explosion of six trillion tons of TNT. Comet hunters like Levy use rich field telescopes (RFTs) to visually sweep the sky for comets, but this type of telescope is also preferred for observing all types of faint, deep sky objects such as nebulas and galaxies. Levy had long envisioned a portable telescope that could be used for spectacular wide-field deep sky observing and comet hunting – but one that could be used for high power views of the planets, as well. Of course with David’s love of imaging and sharing the sky, the telescope also had to be a high-performance astrograph and rugged enough for years of public outreach. And now, the new Explore Scientific Comet Hunter telescope puts David Levy’s vision within the reach of everyone.

    The Explore Scientific David H. Levy Comet Hunter is a compact 6" aperture f/4.8 reflector telescope using advanced Maksutov-Newtonian optics. The Comet Hunter is a rich field telescope (RFT), capable of showing faint objects over a wide field of view (generally two degrees or more). Add a high power eyepiece or two, however, and the Comet Hunter becomes an excellent high contrast/high power planetary telescope, as well.

    A review in Sky & Telescope magazine said “Although the Comet Hunter’s emphasis is on wide-field viewing, I would often track down deep-sky objects with a 9mm (81x) eyepiece and then switch to a 5mm (146x) for a detailed look. One evening when the atmosphere was unusually stable, I pushed the magnification to 365x with a 2mm eyepiece. The view of Epsilon Lyrae, the famous Double Double, was particularly impressive with both star pairs cleanly separated and each star’s Airy disk surrounded by a perfect set of diffraction rings."

    Built for Sharing the Sky, the David H. Levy Comet Hunter is perfect for beginning through advanced astronomers and astrophotographers alike. But, most importantly, it’s designed to let you join the Explore Scientific quest to share the adventure of astronomy with the rest of the world. A portion of the sale of each Comet Hunter telescope is contributed to the Sharing the Sky Foundation.

Features of this Telescope . . .

  • Maksutov-Newtonian optics: 6" (152mm) aperture, 731mm focal length, f/4.8 multicoated optical system. 27.4" long (without dew shield). The Maksutov meniscus corrector lens improves off-axis images, as the Maksutov-Newtonian design has only one-third the coma of an equivalent conventional Newtonian reflector. Its round star images are well corrected from the center of the field to very edge, The 46mm M.A. enhanced 99% reflectivity diagonal mirror that directs the light to the focuser at the side of the optical tube is mounted directly on the meniscus corrector, eliminating the spider vanes that hold the secondary on a conventional Newtonian, and thereby eliminating the diffraction spikes on bright stars that are typical of a Newtonian.

  • Multicoated optics: The system’s Maksutov corrector lens is fully coated on both sides with EMD™ (Enhanced Multilayer Deposition) antireflection multicoatings for high light transmission, minimal light scatter, and excellent contrast.

  • Dual speed 2" Crayford-style focuser: The precision-made no-backlash focuser has dual-speed focusing. There are two coarse focusing knobs. The right knob also has a smaller concentric knob with a 10:1 reduction gear microfine focusing ratio. This provides exceptionally precise image control during high magnification visual observing and critical DSLR or CCD imaging. The large focus knobs have ribbed gripping surfaces so they are easy to operate, even while wearing gloves or mittens in cold weather. Two knobs underneath the focuser lets you adjust the tension on the drawtube to accommodate varying eyepiece/photo accessory loads, as well as firmly lock in a photographic focus. An extension tube and a 1.25" eyepiece/accessory adapter are provided to accept a wide range of visual and photographic accessories.

  • Carbon fiber body: The body and removable dew shield of the 152mm Explore Scientific Comet Hunter are made of woven carbon fiber fabric, encapsulated in epoxy. Carbon fiber, the same material used to fabricate much of the fuselage and wings of the new Boeing 787 Dreamliner passenger jet, has a high strength-to-weight ratio to keep the scope weight down to a very manageable 15.4 lbs. In addition, carbon fiber has low thermal expansion characteristics when subjected to temperature variations. This helps to keep the instrument sharply focused as the ambient temperature changes, which is particularly important during critical long-exposure CCD imaging.

  • Dew shield: The supplied removable carbon fiber dew shield slows the formation of dew on the corrector lens in cold weather to extend your undisturbed observing time. It also improves the contrast, similar to the effect of the lens shade on a camera lens, when observing during the day or when there is excessive ambient light at night, such as a neighbor’s backyard security light. A slip-on metal dust cap is standard that fits both the dew shield and the optical tube itself..

  • Mounting rings and dovetail: The Comet Hunter has dual split mounting rings with a dovetail plate that fits the Vixen-style dovetail slot on the head of many of the most popular medium capacity German equatorial mounts. Such mounts include the Celestron Advanced Series go-to equatorials, the Meade LX80 go-to equatorial, and the Vixen Sphinx and Great Polaris Deluxe equatorial mounts, among others. A spacer/stabilizing bar on the top of the rings provides a carrying handle that makes it easy to transport the optical tube and install it on your equatorial mount.
  • Extended lifetime warranty: This individually serial numbered Explore Scientific telescope is backed by a limited one year warranty, which will be extended to an Explore Scientific transferable lifetime limited warranty when its warranty card is registered with Explore Scientific within 60 days of purchase. Full details on this unique transferable lifetime warranty.
Highest Useful Magnification:
This is the highest visual power a telescope can achieve before the image becomes too dim for useful observing (generally at about 50x to 60x per inch of telescope aperture). However, this power is very often unreachable due to turbulence in our atmosphere that makes the image too blurry and unstable to see any detail.

On nights of less-than-perfect seeing, medium to low power planetary, binary star, and globular cluster observing (at 25x to 30x per inch of aperture or less) is usually more enjoyable than fruitlessly attempting to push a telescope's magnification to its theoretical limits. Very high powers are generally best reserved for planetary observations and binary star splitting.

Small aperture telescopes can usually use more power per inch of aperture on any given night than larger telescopes, as they look through a smaller column of air and see less of the turbulence in our atmosphere. While some observers use up to 100x per inch of refractor aperture on Mars and Jupiter, the actual number of minutes they spend observing at such powers is small in relation to the number of hours they spend waiting for the atmosphere to stabilize enough for them to use such very high powers.
Visual Limiting Magnitude:
This is the magnitude (or brightness) of the faintest star that can be seen with a telescope. The larger the number, the fainter the star that can be seen. An approximate formula for determining the visual limiting magnitude of a telescope is 7.5 + 5 log aperture (in cm).

This is the formula that we use with all of the telescopes we carry, so that our published specs will be consistent from aperture to aperture, from manufacturer to manufacturer. Some telescope makers may use other unspecified methods to determine the limiting magnitude, so their published figures may differ from ours.

Keep in mind that this formula does not take into account light loss within the scope, seeing conditions, the observer’s age (visual performance decreases as we get older), the telescope’s age (the reflectivity of telescope mirrors decreases as they get older), etc. The limiting magnitudes specified by manufacturers for their telescopes assume very dark skies, trained observers, and excellent atmospheric transparency – and are therefore rarely obtainable under average observing conditions. The photographic limiting magnitude is always greater than the visual (typically by two magnitudes).

Focal Length:
This is the length of the effective optical path of a telescopeor eyepiece (the distance from the main mirror or lens where the lightis gathered to the point where the prime focus image is formed). Focallength is typically expressed in millimeters.

The longer the focallength, the higher the magnification and the narrower the field of viewwith any given eyepiece. The shorter the focal length, the lower themagnification and the wider the field of view with the same eyepiece.

Focal Ratio:
This is the ‘speed’ of a telescope’s optics, found by dividing the focal length by the aperture. The smaller the f/number, the lower the magnification, the wider the field, and the brighter the image with any given eyepiece or camera.

Fast f/4 to f/5 focal ratios are generally best for lower power wide field observing and deep space photography. Slow f/11 to f/15 focal ratios are usually better suited to higher power lunar, planetary, and binary star observing and high power photography. Medium f/6 to f/10 focal ratios work well with either.

An f/5 system can photograph a nebula or other faint extended deep space object in one-fourth the time of an f/10 system, but the image will be only one-half as large. Point sources, such as stars, are recorded based on the aperture, however, rather than the focal ratio – so that the larger the aperture, the fainter the star you can see or photograph, no matter what the focal ratio.

This is the ability of a telescope to separate closely-spaced binary stars into two distinct objects, measured in seconds of arc. One arc second equals 1/3600th of a degree and is about the width of a 25-cent coin at a distance of three miles! In essence, resolution is a measure of how much detail a telescope can reveal. The resolution values on our website are derived using the Dawes’ limit formula.

Dawes’ limit only applies to point sources of light (stars). Smaller separations can be resolved in extended objects, such as the planets. For example, Cassini’s Division in the rings of Saturn (0.5 arc seconds across), was discovered using a 2.5” telescope – which has a Dawes’ limit of 1.8 arc seconds!

The ability of a telescope to resolve to Dawes’ limit is usually much more affected by seeing conditions, by the difference in brightness between the binary star components, and by the observer’s visual acuity, than it is by the optical quality of the telescope.

0.76 arc seconds
This is the diameter of the light-gathering main mirror or objective lens of a telescope. In general, the larger the aperture, the better the resolution and the fainter the objects you can see.
The weight of this product.
15.4 lbs
Telescope Type:
The optical design of a telescope.  Telescope type is classified by three primary optical designs (refractor, reflector, or catadioptric), by sub-designs of these types, or by the task they perform.
Based on Astronomy magazine’s telescope "report cards", scopes of this size and type generally perform as follows . . .
Terrestrial Observation:
Observing terrestrial objects (nature studies, birding, etc.) is usually possible only with refractor and catadioptric telescopes, and convenient only when the scope is on an altazimuth mount or photo tripod. Most reflectors cannot be used for terrestrial observing. Scopes with apertures under 5" to 6" are generally most useful for terrestrial observing due to atmospheric conditions (heat waves and mirage, dust, haze, etc.) that degrade the image quality in larger scopes. 
Lunar Observation:
Visual observation of the Moon is possible with any telescope. Larger aperture scopes will provide more detail than smaller scopes, thereby getting a higher score in this category, but may require an eyepiece filter to cut down the greater glare from the Moon's sunlit surface so small details can be seen more easily. Lunar observing is more rewarding when the Moon is waxing or waning as the changing sun angle casts constantly varying shadows to reveal craters and surface features by the hundreds.  
Planetary Observation:
Very Good
Binary and Star Cluster Observation:
Very Good
Galaxy and Nebula Observation:
Terrestrial Photography:
Photographing terrestrial objects (wildlife, scenery, etc.) is usually possible only with refractor and catadioptric telescopes, and convenient only when the scope is on an altazimuth mount or photo tripod. Most reflectors cannot be used for terrestrial photography. Scopes with focal ratios of f/10 and faster and apertures under 5" to 6" are generally the most useful for terrestrial photography due to atmospheric conditions (heat waves and mirage, dust, haze, etc.) that degrade the image quality in larger scopes.
Lunar Photography:
Photography of the Moon is possible with virtually any telescope, using a 35mm camera, DSLR, or CCD-based webcam (planetary imager). While an equatorial mount with a motor drive is not strictly essential, as the exposure times will be very short, such a mount would be helpful to improve image sharpness, particularly with webcam-type cameras that take a series of exposures over time and stack them together. Reflectors may require a Barlow lens to let the camera reach focus. 
Planetary Photography:
Star Cluster / Nebula / Galaxy Photography:
Limited Lifetime
There are currently no Cloudy Nights reviews associated with this product

User Ratings/Reviews from our Customers (www.astronomics.com)
Overall Product Rating: AstronomicsAstronomicsAstronomicsAstronomicsAstronomics(4.00)   # of Ratings: 1   (Only registered customers can rate)

(Only registered customers can rate)

5 - Great (0.00%) (0 users)
4 - Good (100.00%) (1 user)
3 - OK (0.00%) (0 users)
2 - Bad (0.00%) (0 users)
1 - Very Bad (0.00%) (0 users)
0% 50% 100%
astronomics image

Sort Ratings: 

  Show these ratings: ALLGreatGoodOKBadVery Bad

loading request
Showing comments 1-1 of 1
1. Bennie on 5/15/2013, said: AstronomicsAstronomicsAstronomicsAstronomicsAstronomics
First, let me say that I do my homework where a new scope purchase is concerned. I've been an amateur astronomer for close to 15 years and have been taking astro-photos for three.

This scope is a better astronomer than I am. It has let me know where my skill limits are and challenged me to improve. My previous scope is an F-4 newt undermounted on an older Eq mount. I decided to upgrade my kit as a whole and shopped for several months before settling on this scope and an Orion Atlas EQ-G.
As I indicated, I very much like the scope. I thought that a fast scope of any kind would exhibit field curvature or coma and so was originally shopping for an >F-6 refractor. I'm glad I gave this one a chance. I don't have an unlimited budget, but this was indeed money well spent. If you are serious about AP, this is a good upper mid-range scope and should be considered.
Coma is not a problem, I have to look hard to spot it, and can only do so at the very limits of the field. All aberrations are slight and are well outside of the APS-C frame of my Canon 1000D. I was at the limit of my previous scope. I believe this one will allow me to progress "less difficultly" up the already steep learning curve of AP.
In my opinion, the finish is a thing of beauty. The scope is well protected in a hard case with fitted foam interior and can be stowed with rings and dew-shield attached. The rings are a nice touch too, doubling as a carry handle when mounting the scope (no moment of fear). The optics are well thought out. The finder is very nice indeed and feels well built, its adjustable illuminator is easy to use, just watch that you don't accidentally turn it on while stowing it. The focuser is smooth and easy to use. It supports my Canon well. The scope cools down quickly and is ready before I am. I've taken some nice shots since I bought it. The scope frames M81-M82 nicely at prime focus.

The secondary collimation screws are difficult to use, and one of the primary collimation knobs feels "a bit wrong". I'm loath to disassemble such a beauty and will be calling on ES to fulfill their warranty in this department. The scope is prone to dewing (as are all scopes with a front element). Some form of active dew control will prove necessary if you observe in a humid climate.

This is the second scope I received. While the first arrived very quickly, the secondary holder had come loose during shipping. As a result, the primary and secondary were both a tragic sight. This was (without disassembly to check) seemingly due to a loose center screw on the holder itself. Ordering from Astronomics was worry free in that regard though. They bent over backwards to see that I had my scope in my hands as soon as possible afterward. I do commend Michael and the rest of the group at Astronomics on their customer service. The second scope was packed much more thoroughly than the first. Possibly an indication of a change in practice?

There are some very nice scopes available these days for similar amounts. Do your homework and find the one that suits you. Remember to leave budgetary room for a good solid mount (the Atlas carries this scope and all my imaging kit easily and is an excellent choice.) If you feel the ES152 agrees with what you are trying to accomplish... Well you could do a whole lot worse. I'd do it again, problems included.

Clear Skies,
Was this comment helpful? Yes No   (50 people found this comment helpful, 1 did not)
Showing comments 1-1 of 1
We haven't recommended any accessories for this product quite yet... check back soon or call one of our experts (1-405-364-0858).
  • Dual tube rings with Vixen-style dovetail and carry handle
  • 2" dual speed Crayford focuser
  • Carbon fiber body and removable dew shield
  • Dust covers
No documents have been associated with this product.
No videos have been associated with this product.
There are currently no formulas associated with this product
Explore Scientific - David H. Levy Comet Hunter 6" f/4.8 Maksutov-Newtonian

Click icon(s) below & hover image above for zoom

Explore Scientific - David H. Levy Comet Hunter 6" f/4.8 Maksutov-Newtonian
 AstronomicsAstronomicsAstronomicsAstronomicsAstronomics (Average: 4.00 | Users: 1)  Only registered users can submit ratings - Register Here
Our Product #: ES152MN
Manufacturer Product #: MN06048CF-05
Price: $799.99  Ground shipping: $29.95 - Click for more info
Sorry, but due to its weight or classification, this product does not qualify for free ground shipping.
MSRP: $2000.99

 E-mail this product to a friend E-mail this product to a friend

Your Email:  
Your Friend's Email:  
Confirm Friend's Email:  

  200 characters or less

An email containing a link to this product has been sent to the email address you provided.

Clear Skies!

 Have a question? Do you have a question about this product?
 Found a better price? Found a lower price? Click to let us know... or call 800-422-7876 before you buy.

If you’ve found a lower delivered price on this product, let us know about it below. We’ll do our best to meet or beat that price and will get back to you within one business day with our best offer. Thanks for giving us the opportunity to give you a better deal.

Your Name:  
From Who:  
Context:  Magazine AdOnline
Website Address:  
Cut and paste the web address into the box above
Your Email:  
Confirm Email:  

We’ll do our best to meet or beat that price and will get back to you within one business day with our best offer. Thanks for giving us the opportunity to give you a better deal.

Clear skies,

The Explore Scientific David H. Levy Comet Hunter is a very portable Maksutov-Newtonian rich field telescope that lets you observe and image multitudes of faint deep space objects, the Moon, and planets . . . in addition to hunting comets.

. . . our 38th year