A High Definition Telescope? Yeah… The Celestron EdgeHD!

Article Updated: 26 Apr , 2016

In this new generation of everything high def – from computer screen to televisions – is it possible to create a high definition telescope? The answer is yes… And the designer is Celestron. As always, I keep my eyes and ears open when it comes to the latest in astronomy equipment. While I’ve seen a lot of things come and go over the years (including other Ritchey-Chretien and astrograph knock-offs), the Celestron EdgeHD is a design that I think really deserves a closer look…

schmidt-cassegrain_telescopeFirst let’s start the story off where it deserves to be started… the basic Schmidt Cassegrain design. Some four decades ago, the SCT was cutting edge technology. Its predecessor the Cassegrain, used a primary concave mirror and a secondary hyperbolic convex mirror to focus the light back through the hole in the primary to the eyepiece or camera. The Schmidt design allowed for a corrector plate to be added to the optical path to help eliminate spherical aberrations – the increased refraction or reflection of the light rays when they strike near the mirror’s edge. This produced great flat-field images and long focal lengths in an extremely compact design – but it also introduced a very expensive telescope. One the average consumer couldn’t afford.

Enter Celestron…

In 1970 Celestron telescope designers and engineers announced a revolutionary method of producing Schmidt-Cassegrain telescopes at a reasonable cost and in volume. This optical breakthrough was incorporated in the first Celestron C8. The popularity of the C8 Celestron telescope in the consumer marketplace led to the C5 Celestron telescope and then to larger versions, including an 11″ and 14″ telescope. The “orange tube” telescopes became an instant classic and many of them are still in use today… But the design could be a little bit better, couldn’t it? Yeah. It could be aplanatic.

Aplanatic telescopes can be designed with two aspheric mirrors, configured to correct spherical and coma aberrations – a design which minimizes astigmatism and can be optimized to have no vignetting across the field. What’s more, the aplantic design also allows for a significant reduction in scale sizes when it comes to astrophotography, making them extremely compatible with finely-pixilated modern imaging equipment, like CCD cameras. But that would also make it very expensive wouldn’t it? Yeah… It would. But still, that design could get a little bit better couldn’t it? Sure. It could be an astrograph!

In this case, the astrograph is a telescope designed for the sole purpose of astrophotography. Not so great if you want to use it visually… But just dandy if you’re interested in wide field surveys of the night sky. It’s a pure research grade telescope – designed to work in conjunction with a specific shaped photographic plate or CCD detector. With an astrograph you could work on things like astrometry, stellar classifications and, with time, even proper motion of nearby stars. An astrograph means the possibility of finding things like asteroids, meteors, comets, variable stars, nova, and even unknown planets. But an astrograph means you’re talking about a mighty expensive telescope, right? Right.

Enter Celestron…


Just like 40 years ago when Celestron revolutionized the affordability factor of the Schmidt-Cassegrain design (once also the domain of researchers only), they are about to revolutionize amateur astronomy once again by giving the world its very first high definition telescope – the Celestron EdgeHD.

Is Celestron making promises it can’t keep? Let’s take a look at the track record of some major telescope manufacturers.

It hasn’t been that long since Meade also introduced a similar design telescope known as the ACF, or Advanced Coma Free. It was a knock-off of the Ritchey-Chretien design, and supposedly free of third-order coma and spherical aberration, and heavily advertised as being as the same design as the Hubble Space Telescope. Well, we all know what happened right off the bat with the Hubble, don’t we? Darn right. One little wrong tweak in the optical design led to a major Hubble error and one wrong move in poorly executed RCT design will lead to fifth-order coma, severe large-angle astigmatism, and comparatively severe field curvature.

When companies compete with comparative design models for the consumer, they’re putting out a lot of advertising hype your way. But let’s cut to the chase. Two companies… Both produced a sky navigation product – one failed and one endured. Which one? Yeah. The Celestron SkyScout. You’re getting the picture. Let’s take our own IYA Live Telescope as another example. The Meade ETX lasted through 28 observations and I have a Celestron 114 that’s 22 years old and I can’t even begin to fathom how many times it’s been used. Try calling or writing the companies for customer service or questions… See which one answers you and which one doesn’t.


Will the Celestron EdgeHD telescope be all that? The image you see here was taken by Andre Paquette using Celestron EdgeHD Optics. I’ve examined it upside down, backwards, forwards and from edge to edge… and what I see are perfect stellar images. (Open the full-sized image and check it out yourself. You’ll be impressed!)

edgehdsellsheet_Page_2_Image_0005Celestron promises the light becomes more concentrated when focused precisely. This maximizes image brightness, improves resolution and limiting magnitude when compared to telescopes of equal aperture. I know for a fact that you can’t beat Celestron’s Starbright XLT coatings, because I’ve never had to recoat a Celestron mirror yet. I look at the modern ergonomic design and I don’t see “cool” the same way as others… I see a self contained unit that isn’t going to be dragging or snagging on things – one with cooling vents located on the rear cell allow hot air to be released from behind the primary mirror. I see a telescope that’s going to perform incredibly in both visual and photographic capabilities…

11093_cge_pro_1100HDSo where’s the bottom line? The cost. Don’t start selling your gold dental fillings or thinking about taking out a second mortgage on your home, because Celestron has done it again. Just like so many years ago when they made the SCT affordable to backyard astronomers, they are now putting cutting edge, research grade design telescopes into the realm of possible. The average price is only about 1/3 more for the optical tube assembly than a standard SCT and it gets even lower as the aperture goes up. If you need the complete telescope package with a mount and tripod? Sure. It’s expensive – but the high quality of the mount is what you’re paying for and it’s worth it. (Remember two little telescopes – one that lasted through 28 observations and one that’s still going strong after 22 years.) What kind of faith do I have in Celestron? The same faith I’ve always had. Every Celestron product I’ve purchased over the years is still functioning… and the same cannot be said of other “M”anufacturers.

Go on… Take a look at the Celestron EdgeHD for yourself! You’ll find much more information and illustrations at the Celestron EdgeHD Tour pages, and you can take a look at pricing, specifications, and other information through Celestron’s premier dealers such as OPT, telescopes.com, Scope City, High Point, Hands On Optics, Astronomics and Adorama.

What will they think of next??

10 Responses

  1. Dark Gnat says:

    Slightly off topic:

    I recently got the Celestron Binocular/Green Laser/Red flashlight kit, and I gotta say I’m impressed. I’m on a tight budget, so this was perfect. I can clearly see Jupiter’s 4 largest moons, Uranus, and lots of galaxies. I’m looking forward to veiwing Venus and the Moon, among other things.

    The laser is cool, too. I love lasers, and this was an excellent deal. The red light will come in handy, as well.

    I think I might be saving up for a Celestron scope, assuming I don’t get any more pay cuts. πŸ™‚

  2. Sili says:

    You’re almost making me wish for nieces/nephews and godchildren.

  3. Astrofiend says:

    Let me just preface this by saying it will come across harsher than intended – I enjoy your articles and the few exchanges that we’ve had in the comments section, BUT

    Jesus – that sounded pretty much like an AD to me, not a review. Big difference.

    Something to get of your chest in regards to Meade Tammy?! Any disclosures to make? I mean, come on – the whole article is a Meade put down and a Celestron ‘big up’. What’s with the consistently negative wording in regards to Meade? I.e:

    “It was a knock-off of the Ritchey-Chretien design”

    “supposedly free of third-order coma”

    “and heavily advertised as being as the same design as the Hubble Space Telescope. Well, we all know what happened right off the bat with the Hubble, don’t we?”

    …to mention but a few examples, and then you basically worship Celestron:

    ” they are about to revolutionize amateur astronomy once again by giving the world its very first high definition telescope – the Celestron EdgeHD.”

    “I know for a fact that you can’t beat Celestron’s Starbright XLT coatings, because I’ve never had to recoat a Celestron mirror yet”

    “The cost. Don’t start selling your gold dental fillings or thinking about taking out a second mortgage on your home, because Celestron has done it again.”

    “What kind of faith do I have in Celestron? The same faith I’ve always had.”

    Where do I start here? You’re criticising Meade’s ACF; for what exactly? It’s answer to improved optical design, or the advertising campaign that they ran? You rubbish it, and yet you’re plugging this scope from Celestron hard for it’s (apparently) far superior optical design? How is it qualitativlely or quantitatively better than an ACF? Is it purely based on an axe you have to grind with Meade, or some sort of uber brand-loyalty to Celestron?

    I’m no Meade or Celestron die-hard, but lets have a little look at why Celestron have sucked particularly badly until recently.

    Celestron went through a pretty poor period for about the last 15 years. Almost no innovation that made much difference to anything. They were constantly playing catch-up to Meade when it came to the main scope lines – the LX200 and LX90 were leaps and bounds ahead of the competing Celestron options in almost any area in which you’d care to compare them, and far cheaper to boot. To make matters worse, Celestron scopes looked downright ugly, and had a cheap ‘toy-scope’ look to them. Now, optics from both companies are great at the moment, and have been for some time. But nobody wants a telescope that has been designed to look ‘space-age’, like Celestron’s hideous Ultima series effort of a few years back for example.

    I think they are somewhat redeeming themselves with their new offerings such as their superb new mounts and this scope certainly looks like it may be a very capable performer. But it still has that bloody molded plastic cheap look happening on the rear cell. For god sake Celestron – get over the curvy plastic and ugly molded knobs – you wouldn’t see any self-respecting refractor of even relatively poor quality with such abhorrently cheap looks, so why is it OK to do it on a catadioptric? That goes for you too Meade, though to a lesser extent. Don’t tell me it’s price either – I’d rather spend a couple of hundred more for some decent knurled metal knobs and a more substantial looking rear cell than go without.

    Anyway, now Meade has headed south too (both metaphorically and literally – they now assembly in Mexico which isn’t necessarily a bad thing in and of itself, until you consider that it was done specifically to cut costs).

    Why the rant? Celestron and Meade are pretty much the same company looking at each other in a mirror. They offer roughly the same products, of roughly the same quality (with both companies varying in quality of product and product support over time), and have both played a part in the advancement of our hobby. They both offer solidly performing scopes at reasonable prices for those who can’t afford the ultimate equipment, but want some very fine equipment none-the-less.

    This article was so blatantly an anti-Meade rant that I can’t quite believe it was on UT. The pro-Celestron was spew-inducingly over the top – I haven’t even seen reviews that glowing for RCOS, obsession or Astrophysics scopes – pretty much acknowledged to be the finest scopes around that any amateur could lay their hands on.

    All I can think of is that Meade screwed you over somehow and that this whole article was engineered with a view towards vengeance…

  4. Fraser Cain says:

    Celestron doesn’t pay us to do reviews, if that’s what you’re wondering. Tammy gets gear and does reviews, but I pay her for the reviews, not the telescope manufacturers.

    Tammy’s just naturally enthusiastic.

  5. omnivorr says:

    sorry,… but gush like that is anathema to intelligent interest in the product.
    This “review” sounds like it was written by a ‘freshman’ in the Goebbel’s school of hypermedia studies.
    …or did it come from “The Pond’s Institute” of anti-aging snake-oil?

    …it’ll all end in botox/lobotomy, but gravity will win!

  6. croysk says:

    This “review” is so terrible it made me sign up to, well, basically to complain and agree with the “astrofriend”s post above. This post may seem harsh, but this is the first time I’ve ever felt the desire to do this. This article really is that bad.

    I am no great fan of Meade, nor of Celestron. I own two Celestron ‘scopes – a C8 and C11, among other manufacturers (a little Meade ETX90, Borg, Takahashi, etc). I accept the C8 and C11 for what they are – cheap compact scopes with relatively large aperture for the cost. I agree with pretty much everything “astrofriend” says above, though I perhaps wouldn’t go as far as to accuse Tammy of “astroturfing”. Having said that, there has been a lot of gushing over Celestron equipment in the past, though nothing quite like this!

    This is disheartening as I very much enjoy Tammy’s “What’s up” articles and most post on this site. The otherwise good quality just makes this “article” stand out even more.

    Not only is this an overly enthusiastic “review” of a scope the author doesn’t seem to have used, what’s annoying is the ridiculous non-sequiturs and silly arguments in favour of the ‘scope and occasionally against Meade – which in themselves are, of course, irrelevant. Is this a post about a new ‘scope or about how bad Meade is/has become (and they are bad)? The Meade bashing doesn’t grate so much, nor even does the enthusiasm – I’m sure these scopes will be a nice option for some people – I may get one myself.

    What’s annoying are the completely silly arguments put down, some of which fail logic, others which belie ignorance of optics and equipment in general. This goes both ways – not only are there poor and inaccurate arguments in favour of these ‘scopes, there are important omissions – like Celestron finally doing something about the terrible mirror flop inherent in these cheap designs (which Meade also suffer from of course). This is good thing, but no mention. Likewise no mention of thermal problems other than the tiny grills that look like they will achieve nothing. I could continue (the potted history of the designs, completely wrong description of “aplanatic”, etc..). Perhaps the worst is the argument that as the HST optics were incorrectly fabricated (not incorrectly designed), any RC design (of which it has been pointed out that the Meade RCX/ACF designs are not) therefore must somehow also be defective. A number of non-sequiturs and just plain wrong on a number of levels, simultaneously. So bad it is quite impressive!

    Overall the article is focussing on the new design (shiny new shiny new!). Except that it’s not new, and there’s a chance it could be implement poorly – just like most of the commercial SCTs available. This is fine, they are cheap. These will be a bit more expensive, with a better design and look like they will be built better. This does not warrant the hyperbole of this article.

    I will finish by saying I am truly disappointed. Tammy, stick to your engaging and informative descriptions of the night sky, where your enthusiasm doesn’t grate so much, and of which you seem to know far, far more about.

    All the best.

  7. Jon Hanford says:

    Btw, the galaxy cluster presented in the article is none other than the Coma Cluster aka Abell 1656, for all galaxy-heads out there πŸ™‚

  8. a little pointless time wasting because anything i say can and will be used against me…

    why do i feel the way i do? let me count the ways. two decades ago i spent over a year waiting on my first big M telescope. i love it. i would never part with it because the optics are perfect. everything but the optics fell apart within two years and i’ve had to totally redesign it to use it. the next M purchased with my own money had great optics and was a goto… it fell apart. the next M was binoculars with great optics that went out of collimation on the first trip. the next M was a very expensive telescope for the observatory that promised to bridge the gap – hundreds of dollars later we got it to work and now about a year later the incredible optics need recoated. the next M was a little goto that i loved, rated highly and spent an incredible amount of money to ship to another part of the world to share the view with all of you… and it fell apart. another M promised to show and tell… and turned into the exorcist. through it all, i have been exceptionally kind. went through every channel at my disposal and used extreme diplomacy. i have been ignored. i have been put on hold forever. i have not had long distance calls returned. i have been offended. i have been disregarded. i have been told i am sol.

    i have C products purchased with my own money that i have literally beat the tar out of. i do not observe like you do. i work for a living. when i feel scientifically minded, i like bells and whistles. when i am working, i want something i can haul around forever and not worry about beating this little knob or that little gadget off of it. i want something i can throw in the trunk of my car… and leave it there for 10 years. i want to be able to bungee cord it to a harley davidson, pack groceries around it, and haul that bad boy from one end of the earth to the other and know it’s going to work when i set it up again. i have 4 C telescope and all of them have been worked hard and still perform. i am practical and so are C products. if you don’t like the ergonomic design? tough. because that’s what the ergonomic design means. it means you’re not going to whack it on the garage door taking it out and destroy your scope. it means you can take it in and out of a carrying bag a thousand times and no screws are going to get lost. it means it really can ride around in your trunk, go through the belly of an airplane and take what you dish out. it may not be the most perfect design that ever was – but the daggone thing will hold together. am i purposefully hard on my equipment? absolutely not. i am a professional. but i do not expect to have to pamper something to make it work.

    and i do not expect something i pay my hard earned money for to fall apart.

    are you a ford man? or a chevy gal? would you rather ride a honda or a harley? in my world, there is no relevance – only performance and what i can afford. i would rather drive a ferrari – but i can afford a mitsubishi. (besides, my telescopes fit far better in its trunk.) do you want me to review a borg? good. tell them to send me one… because the products i review are the products i can afford or from the companies that have the guts to put their stuff on the line for an honest opinion. chances are, if i can’t afford it… neither can you… so that makes us even, eh? i’m incredibly honored when a company like vixen or televue takes the time for me… because there are companies out there that i’ve bought a whole lot of their products that won’t even return a simple phone call when i have a problem.

    give me equipment i can afford, use and depend on and i will give you my loyalty – and i don’t give a rat’s hindquarters what your name is. if you think i gush? well, heck… you’d love my astronomy programs! it’s no wonder our observatory is so popular, cuz’ i spew astronomy like old faithful. i saw something that was new, might very well revolutionize the way we practice backyard astronomy and thought you might like to know about it. if i’ve made an error in how you think i’ve explained something should work or thought i’ve knocked a design? well, read it again – or write it better and post it. i’m not offended. if you think i should stick to just describing the night sky and what you can see out there? well, brother… then you’re the one outta’ luck… cuz’ someone has to be out there with real equipment under a real night sky making sure you really can see this real stuff.

    but that’s just my opinion… i could be wrong. πŸ˜‰

  9. William928 says:

    WOW! i don’t know enough technically about scopes to comment on who’s right in this argument, but I do believe a few of you were a bit harsh with Tammy. This post is really directed at Tammy to get her opinion on which scope I should purchase as an amateur astromomy buff who has had a scope since high school (30 yrs. ago). I’ve looked at Orion Observer 70MM Altazimuth Refractor, Orion Transporter 70mm Refractor, and the Celestron Astromaster 76 Reflector. Would a reflector or refractor scope be best? i’m strictly interested in astromomy, so I believe a reflector may be the choice? I’d like to stay under $300. Any advice you can offer would be much appreciated.

  10. hi, william…

    here’s where people are going to be a bit shocked, because i’m not going to particularly recommend celestrons you chose in this case. while their lower cost, entry level model scopes are just fine and i think the sky scout scope 90 refractor (which doesn’t need the skyscout to operate and is a very nice, very durable scope in the price range) that would fit the alt/az design i’ll bet your familiar with, but i’m going to first recommend either the vixen A70LF refractor telescope with mini porta mount (average cost $300) and secondly the orion ShortTube 80 EQ refractor (average cost $300).

    why would i suggest those two scopes to you over my beloved choice of celestron – especially since the skyscout scope 90 is larger aperture, fits the same price range and is a rugged performer? let’s just say i got some clues from your post…

    you are not a kid and you have used a telescope before at one point in your life. chances are, once you start enjoying one again and realize just how relaxing astronomy can be that it won’t be long until you’ll want to upgrade to a larger optical tube and by starting with the mini-porta mount you’ve got the “key” to up to 8 lbs. of telescope body without buying everything all over again. these are darned durable alt/az and the vixen dovetail system works with a HUGE amount of telescopes – not just vixen – so your options become wide open. same goes with the orion… it comes with an orion eq-1 equatorial mount – it doesn’t work the same as the alt/az and it will only hold 7 lbs. – but you could add tracking to it if you wanted and the scope is really sweet… really. it’s light duty… so if you take care to make sure the mount is balanced, etc., it will also last – but not as well as the porta mount.

    now for the optics. all of the scopes mentioned here have excellent optics. all three are refractors. all three come well equipped with the accessories you’ll need to get you going. the 90 will give you the most aperture, the 70 will deliver the best, razor-edged image and the 80 will give you a walloping field. why no reflectors in this selection? because the reflectors that fall within this price range have mounts that could leave it little bit more to be desired. There’s always a trade off. To stay under or at $300 and get that big newtonian “yes, ma’am… that’s what i’m talking about!!” whoopee, i’d suggest the orion XT6 SkyQuest dobsonian. however, there’s a trade-off here, too… unless you come from the land of munchkins, you’ll need to put the scope up on something to use comfortably. (round patio stones are perfect, a milk crate works, or you can also sit down if so inclined.)

    i hope i’ve helped! there’s so many things i didn’t even touch on that comes from experience, like how each mount from each company can be adapted to binoculars, etc… and how proper balance, watching how much weight you put on them, etc. makes a mount last and how to adapt different types of telescopes to each one, but then, i’m only good for describing what’s out there, ain’t i? giggle… πŸ˜‰

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