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Celestron PowerSeeker 127EQ
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Celestron PowerSeeker 127EQ
I recently had a contractor doing some work for us, who, after seeing my ‘scope room’, mentioned that he too had a scope and maybe I could have a look at it as it didn’t seem to be performing……at all.
So
of course, I said yes, I mean what is better than being able to take apart
someone else’s scope?
This 127EQ scope sits at the bottom of Celestron’s beginner scope range. And with good reason.
It features a 5” primary and a final 1000mm focal length in a 24” long optical tube. This optical sorcery is accomplished by placing a 3X Barlow lens in the focuser tube and shortening the focal length of the primary to F3.5. This is called a Bird-Jones design. In reality, it is a pseudo Bird-Jones design.
The real Bird-Jones design called for a high-quality spherical mirror and a dedicated corrector lens in front of the secondary. It was expensive to make, and a devil to collimate accurately.
The 127EQ uses an F3.5 spherical
mirror which is guaranteed to introduce all sorts of spherical aberration to
start with. The Barlow lens alone can’t address these S.A issues (the Bird
Jones design called for a specific corrector – not a Barlow Lens), and because
the 127EQ has the ‘correctgor’ in the moving part of the focuser, it’s a
constantly moving target. (The original BJ design had the corrector in front of
the secondary mirror (ie: not moving)
I suspect that Celestron adopted this approach because it allowed them to drastically reduce the overall size of the OTA from a shipping perspective, and still be able to make extravagant magnification and capability claims. (Which is probably why my contractor bod probably bought one).
By comparison, Celestron’s lowly 114mm/F8 straight Newtonian is a stellar performer. (See my review on this site – The Unsung Hero)
Unfortunately, these optical compromises do nothing to help the scope’s performance.
So, where do I start?
First off, the scopes optics were filthy. Not Celestron’s fault of course, but it certainly didn’t help the cause.
Secondly, after a full cleaning and careful re-alignment of the mirrors (you really need to take the corrector/Barlow out of the focuser tube to do a meaningful collimation (how many Newbies will do that?), the scope only puts up wishy washy light flooded images. I even went to the trouble of blackening the inside of the OTA when I had it apart – it made no difference.
The
spherical aberration is brutal. Only the center 1/3 of the FOV could be
considered ‘sharp’. The supplied cheap eyepieces (15mm and 9mm Plossl) did
nothing to detract from this. They only introduced more edge of field
fuzziness.
The pic on the left was taken of my telescope pier about 100 yards away using an iPhone looking into the supplied 15mm eyepiece (approx.. 66X) You can see the field curvature in the flared pier sides. )
The supplied 3X Barlow should just be thrown out. The only reason it’s there is to make Celestron’s extravagant magnification claims a mathematical reality. You could never use it in practice.
The only ray of hope on this scope is that the EQ1 equatorial mount is just serviceable. The axis locks are just thumbscrews, and the movements are jerky and shaky. The short 5” OTA is taxing its limits. Here again, the newbie presented with the un-intuitive movements of an equatorial would probably just give up.
And that’s why so many of these scopes are for sale at garage sales or wherever. Poor optical performance and un-intuitive/shaky mounts.
Celestron has ‘flooded the zone’ with feel-good advertisements, distributor ads and paid influencer plugs to the point where it’s hard to find a worthwhile review on these scopes.
Bottom line:
They’re worthless – don’t buy one. If someone gives you one, put it in the garbage and cut them out of your will.
They put out so much good astro gear. I can only think that this scope and other bargain basement scopes must fall under a different division. But I suppose as long as Walmart, Costco and the rest of the retailers can sell them to an unsuspecting public – it will continue. Celestron should be embarrassed to sell this scope.
I can only wonder how many budding astronomists have been turned off by scopes like these?
I haven’t broken the news to my contactor yet. He hasn’t finished the job…
- rosecityred, Bob Campbell, JMP and 23 others like this
43 Comments
Baloney.
I agree that there are better choices for your first telescope, given that you do enough research into shopping before you buy and the best telescope is the one that gets used.
When my wife and daughter bought me my first adult telescope for my 65th birthday in 2014, I chose the 'scope. I googled and picked the one that was most like the Criterion 4-inch reflector that I had when was 11-17 years old in 1960-66. People here disparage that Celestron 130EQ for its spherical mirror. I owned it for five years before I donated it to the Goodwill and went to refractors for being easier to set up and carry. I filled a notebook with that so-called "hobby killer" and recorded views that I had to work at to get later such as Messier 4, Messier 7, and Messier 80, and Mars among others.
The fault, dear Brutus, was not in the stars (or the telescope). I lacked a mentor who could help me understand how to observe. Star parties did that for me because I could learn from others.
A $6000 Takahashi would not have made me a better observer.
And BTW, even though I came and went in my local club when I could make star parties, in 2019-2020, I joined a lot of clubs, the BAA, the SPA, IOTA, ASP, AAVSO, etc, etc. And I learned a lot there. I winnowed them down to the ones that worked best for me and my context. Today, I edit "This Month in Astronomical History" for the AAS. (See here: https://had.aas.org/.../astro-history)
Best Regards and Clear Skies,
Mike M.
Hi Mike,
I wholeheartedly agree. 5 minutes of someone's time can save a lifetime of disappointment and frustration. Nobody really wants to malign a telescope, but sometimes it can be regarded as a civil service....:-)
I should also say for the record that spherical mirrors, in and of themselves are not necessarily bad.
The ubiquitous 114mm/900mm FL plain jane Newtonian is very good, and the Russian TAL mfr. produced some excellent longer FL spherical mirror based Newtonians. But the common factor here is longer focal length - Typically F8 or longer where the departure from a parabola is small enough as to not make a huge difference.
In fact, the TAL mirrors were figured to such precise, smooth spheres that their F8 spherical mirror would easily beat less finely figured paraboloidal competition.
As a proud owner of a TAL 100RS refractor I can attest to their excellent optics
My first telescope in Canada was a crappy 115 CA$ Celestron Astromaster 70 AZ from Walmart, very far from high quality optics.
However, I used it for almost 2 years to observe lunar occultations and eclipses, variables, doubles, open clusters and some planetary as well.
Note that I wasn't a rookie, I knew what kind of objects were within reach of the 70 AZ and what would they look like.
At some point, I exhausted the list of available objects (light pollution + small aperture limitations) and upgraded to a 6" F/8 Dobson.
Do I regret using the 70 AZ ? Not at all. It was 115 CA$ well spent !
Sadly, many rookies throw 1000$ - 2000$ (even more) into their first scope without any clue of what to observe or photograph, how to do it, what does it look like, etc.
So, the "Celestron PowerSeeker 127EQ" is not a bad choice as long as you know exactly what to expect from it.
I actually have a 127EQ here (came in a 2-scope goodwill bundle), of which I just wanted the starsense phone mount from ... already flipped the LT80 locally, 127EQ is the leftover... basically a freebie.
I think it makes a good cataract/eye disease simulator. One gets twirls and odd things one doesn't expect to see using a telescope.
If I get around to collimating it one day, perhaps I can get it usable, sorta. Maybe it requires a mask or something so only like half the mirror is used... not sure.
They come with excellent 6" rings.
There is a simple truism. A person actually meant to be a amateur astronomer will make do with just about any bottom-feeding telescope until they get a better one. Those not meant to be amateurs shove scopes in closets.
Agreed!
My first scope in High School was a junk Tasco 3" Newtonian. It never discouraged me. In fact, it made me want to research and own better scopes when I get older
And here we are LOL!
This was my very first scope, and it nearly ruined the hobby for me.
It would only do that if people were clueless that better optics could be had. I went to my first star party at age 9, I had some dept store piece of crap 50mm, but I knew there was better. One look through a big Newtonian, that was it. Now that optics are so cheap relative to income (at the time, the cheapest six in Newtonian was around $200 which equates to $1500 today) that there is no excuse not to have something worth looking through.
The risk that manufacturers take with entry level is "typecasting" or association with bad performance and disappointment. We really will never know who abandons astronomy.... or who never purchases from that same company ever again. However, their management must do the math, but I suspect they are operating on Barnum's principle of a fool born everyday...
I got hooked by a Goodwill cheapo. I now have thousands invested in good performing optics/computers. But I will never spend a penny on the M brand again.
Yep, did that mistake and purchased this scope as my first foray into astrophotography. Back then i did not know about spherical mirrors, so i fell for the stated focal length and price, hoping i could get started with that...
Didn't take long for me to shove it in a bag where it's been ever since. I now own an Orion 6in Astrograph.
From personal experience with a friend's 127EQ, it's the mount that creates the most issues for beginners. The learning curve for a EQ mount is steep and most beginners, save the most determined ones, will give up after a while. On top of that it is barely steady enough for the scope.
Aligning the viewfinder is another problem that we faced. No matter how we turned the screws the crosshairs would never align with the top of the distant tree that we had centered in our eyepiece.
Then they supply a 4mm EP and a 3x Barlow, which is a cruel joke two times over, because 250 power is in itself problematic for this scope and on top of that, beginners chasing magnification will invariable combine both for a laughable 750 power. This power combined with the questionable optics produces very poor views which would be off putting to most people and especially beginners who don't have set expectations (read have high expectations).
For the most ardent of beginners who have crossed all the hurdles the optics aren't too bad at low power and most of the flagship objects in the sky can be viewed and enjoyed. I'd say the EQ 127 instead of encouraging beginners will be off putting to most. A table-top 4" Dobsonian at a similar price point is a better and easier instrument to master.
Cheers,
Shil
We saw that at the first Covid shut downs, expecially from younger professionals in Information Technology who had the disposable income and some technical orientation. They bought over-large Dobsonians and found out that they are no fun to collimate and haul outside on a whim and even less fun to put in a car and take to a dark sky star party.
Thanks!
Mike M.
Fully agree.
Poor optics may be a hobby killer, but a wobbly mount is worse.
EQ mounts are usually difficult for the beginners, most of them don't understand the idea behind RA and DEC axis.
Altitude and Azimuth coordinates are more intuitive, but they come with the hassle of pushing the tube every couple of minutes.
I loved that scope because it was the first I bought (in my mid 50's) The thrill of being able to view Jupiter, successfully finding the double cluster and discovering after numerous unsuccessful weekends that dark skies were required to view star clusters got me hooked on telescopes ever since.
I had gone to star parties in my late twenties and observed through what was a large dobsonian at the time and was somewhat dissapointed with the views expecting Hubble like images and never caught the bug.
So my theory about the telescope hobby is it all has to start with your first purchase and Celestron provides many models to meet an entry level demand into the hobby.
In the end it's more about what you make of something, not what other's opinions are about how you achieve that.
Useful review and warning. I see many of these up for sale on facebook marketplace. I picked up a 114mm version for $50 just to get the starsense smartphone tech off it. Since it has an alt-az mount it is now used as a scope for members of the public to use during telescope tryout events. The views are not too bad at low power so it useful for its current task.
And that is the case with the majority of below entry-level scopes. Celestron's long 70mm refractors are a MAJOR proof of that. Perfectly good optics on mounts that are far too unstable.
Before you throw it away, save the scope rings. They are worth more than the entire scope.
I agree with this assessment, with a few considerations.
A lot of the time, people get this telescope on accident. Celestron pushes this telescope hard on all retail websites, and people are duped into buying one. Either as a gift or as a mistake, they have it now.
Of course we all know it's a very poor value for money. What's critical is that we explain why, and then explain ways to improve the experience of using this entirely compromised optic.
The mount is pretty terrible, the finder is completely useless, and the entire kit might as well be trash. We can also improve contrast instantly by blackening the edge of the corrector (a full 3/4 inch of just raw fine ground glass).
Ragging this telescope is like shooting fish in a barrel. Explaining how to make it worthwhile, that's what's important.
Consider this thread from Sky Muse https://www.cloudyni...erseeker-127eq/ detailing how some of the telescope could be worth fighting for. Not all of the fixes are useful for new observers, but it touches on some of the more critical considerations for telescope design. Uncovering the rear optic, blackening optical elements, baffling, eyepiece selection, focuser mechanics, the list goes on. It's what started me on ATM in the first place.
Celestron should be ashamed of themselves. This scope is junk.
A young couple brought one of these to one of our clubs public star parties. When I bumped into the couple late in the evening, they were frustrated because they had been fiddling with the scope all night long and had not seen a single object. I offered to point it at Jupiter for them. Nope. 30 minutes later, I couldn't get it pointed at Jupiter either. I was stumped. Between the shaky, difficult to use mount, extremely bad collimation, and a finder scope aligned God knows where, I advice to them was to return it for a refund if its not too late.
My preference for scopes like these is to lay them in my driveway and run my truck back and forth over them.
My first scope came from sears back in 1990 from my grandparents. The box images were a bit deceiving to say the least. I remember people asking to look through it to see some far off galaxies. All they got was the moon, which is great but...
Then I got the 127EQ prior to ever finding a forum or talking to anyone. Got bored with it, then hilariously thought I could do AP with one. Bought the motor drive, did the entire "hang a weight thing" and I wasn't impressed. Frustrated I put it in the basement and never touched it again (still down there). I wrote the hobby off is pretty much impossible for me to do. Then randomly a few years later spent a bit of money on a "real" budget setup and finally got my first image of Orion. I will say that moment that it showed up was one of the best moments I have had. Buddy and I clanked beers and said "WE DID IT!"...
I have it but never looked through it. Got it just for the 6” rings which are useful. The counterweight also has been of use to me in other projects, as well as the slo mo cables. I try to “repurpose” instead of throw away perfectly good parts like tube, front lid etc.
I've just been given a Skywatcher version of one of these. I have some experience of this design and can usually coax them into some sort of useable performance. A half decent eyepiece often works wonders for a start. The scope looks unused and quite nicely presented in its blue, black and chrome fittings, who wouldn't want one? A preliminary inspection showed better than average collimation and a terrestrial view at 150x (Baader zoom at 8mm setting) looked promising. The mount was a different story, the RA worm doesn't line up with the wormwheel with no means to adjust it and I've yet to find a position for the drive handles that can be comfortably reached and at the same time not clash with other parts of the mount following a short movement.. The supplied accessories do it no favours. Despite all of this, I wonder what Galileo would have thought of it.
My youngest grandson was given one about 4 years ago by an evil grinch. He grew up looking through my 6" F/8 space commander by Edmund Scientific and my 14" LX200 GPS and knew what he should see. Brought it to me to check it out. After completely dismantling it and changing all collimation screws, adding springs behind the mirror cell, fixing the secondary mirror holder and overhauling the focuser, it was just barely usable. All this led to myself and grandson obtaining the parts needed to build a scope tube pretty much identical to my Edmund scope but 10" F/6 dob. Found a decent eq mount used that ended up being donated. So the only thing positive I can say is that crummy scope led my grandson down the path of learning and obtaining a good scope.