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Celestron Regal 65ED M2

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Celestron Regal 65ED M2: My review


It's about two months that I'm playing with a Regal 65ED M2. Yes, it's a spotting scope, a well-made one, not too expensive and compatible with standard 1.25" eyepieces. Here my impressions.


Intended use

A spotting scope is a refractor plus a 45° erecting prism in a rugged and lightweight package: nothing prevents to point it at the sky. However, the 45° prism is not as comfortable as a 90° star diagonal to observe (but it is much better than a straight through binocular), there is no (easy) system to add a finder or a red-dot and you are limited to 1.25" eyepieces. I think a spotting scope excels if you need a travel, sturdy, grab&go refractor to be used for both nature & sky observations (even if the sky part will get most of the use).


A close up of a gun

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How small all the package (tripod + scope) is. The ES 5.5mm 62° is for comparison]


Specs A 65mm ED spotting scope, with internal focusing and a magnesium housing. Sort of mid-quality zoom: 40°- 62° but with a large eye-lens and a much better eye-relief than the cheap models (20mm spec, can be used with my not-too-thick glasses). Need refocusing when changing magnification. Weight is incorrectly specified: a bit more than 1600gr, and not the stated 1327gr.

The scope has a major mechanical problem: it is back-heavy and it cannot be balanced with a short dovetail. The unbalance is severe, and it makes challenging using the scope on whatever mount, unless with a payload (and weight) that largely exceeds the scope's one. However, the problem can be solved. You need at least a 15cm long dovetail (I use an Arca Swiss one). Luckily, the dovetail can be fixed to the scope using two thumbscrews, so it stays firm once fixed.


A picture containing ground, wall, sitting, object

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The scope with the long dovetail bar


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Note (i) the two thumb-screws to connect the scope to the dovetail
and (ii) how far back the clamp locks the dovetail


Changing eyepiece is not as easy as in a traditional diagonal. There is a self-centering ring and, once you have turned it, some force should be used to pull-out the eyepiece. I think that's normal, as in that way all the system remains waterproof (there is at least one O-ring where the eyepiece is inserted).


Very nice the metal made "case" for the eyepiece, which screws directly on the scope’s body and fully cover the zoom eyepiece (and whatever smaller eyepiece you put there).

The back part (diagonal + eyepiece) can be rotated. Hence, it is possible to mount the scope on a ball-head (see below).


Eyepieces compatibility 

I have tested:

1) The zoom eyepiece (it is obviously compatible). Works best up to 30x (more or less), then the image gets softer.

2) Wide field. A 16mm 68°, for (almost) 24x and 2.85° FOV. It focuses at infinity. This FOV is greater than the maximum FOV provided by the zoom eyepiece (2.5° @16x). All the field is illuminated (I have tested it using two stars with a separation slightly greater than 2.8°). However, there is some vignetting: the edges are not as bright as the center. As I can detect it visually, the vignetting should be equal or greater than 20%. If someone has the same scope and it can test a 20mm 68° or something similar, I would love to see the results. I guess the scope can arrive at least up to 3°, more or less

3) Max magnification. I have tested a 5.5mm 62° for (almost) 70x. It works as it focuses at infinity and the image is usable. Not so good on low contrast targets like Jupiter (but Jupiter always wants low mags w.r.t. the scope diameter), very good on the moon (the moon is entirely framed, barely) and on bright stars.



In another discussion, someone suggested that "If your spotting scope has a collar ring that can be rotated by 90 degrees then a 36-44mm Arca-Swiss ballhead used in alt-az config (rotated into the notch) is solid and cheap."

I agree. I bought a relatively unknown Chinese tripod on Amazon, and it works perfectly up to 70x magnification. With the long arca swiss plate I have, I can perfectly balance the scope. Movements are fluid and I do not have to lock the ball to fix the scope in a given position. The ball head (a clone of the Benro B1) has the main lock and a friction adjustment, plus the pan lock.

The friction adjustment (which is gradual and works as you can expect) is useful. You do not need that when the tripod is perfectly levelled on a flat surface but, as my garden is not flat, when the tripod is not levelled it's useful to have a small amount of friction. I do not have that on the pan movement and, as a result, sometime there is a little slip (The pan-lock is a sort of on-off).


Optical quality

Very good. Star test using the zoom eyepiece at about 30x is surprisingly good (at least at the low magnifications used). Intra and extra focal images are similar, the diffraction concentric rings can always be seen.

The scope is collimated (checked with a cheshire).

Flashlight test: the scope works at full aperture (65mm). NB: the 65mm is an f5.9. The 100mm has a more obtuse light cone at f5.4, not sure if that might stop down a little bit the aperture of its bigger cousin.

The scope (and/or the zoom eyepiece) is very sensitive on your eye's position: if it is not perfectly perpendicular, it introduces some CA. If the head is perpendicular, CA is low (at relatively high magnifications) to almost non-existent (at low magnifications). This effect can clearly be seen on Jupiter for example: if the head is not perpendicular and at 48x with the zoom eyepiece, there is a light violet halo on one side of the planet which disappears when you put the head in the proper position: I have never seen such thing before. PS: on Jupiter you can see NEB and SEB plus the 4 satellites, and the zoom at 30-35x is better than the ES5.5mm at 70x.

Star test #2

I checked again the star test, using the ES 5.5mm 62° at 70x. I confirm the scope is collimated. No color in focus using a bright star. Both inside and outside focus, the concentric rings can be seen, even close to the optimal focus position. Here, the external concentric disk is thicker. There is a very slight green color inside focus. Overall, IMHO the star test is good, especially for a spotting scope.


Daytime use

A field of grass with trees in the background

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Very good. No CA (at least for normal targets, I have not tried to look at antennas or similar things, more at birds, trees and landscape).

Very comfortable to move around on the tripod. For daytime, I only use the zoom, it is not convenient to change the eyepiece every time. I still have to do some serious birdwatching with it.



There is at the moment a heated discussion on Cloudynights about spotting scopes. I can only confirm my initial impressions: for a dual day&night scope, a good quality spotting scope is, IMHO, a very good choice. The scope performs nicely also for astronomy, and not only for daytime use. I do not agree with people that says a spotting scope cannot be used for astronomy.

It is true, a 60-72 ED doublet with a 45° erecting prism and a zoom eyepiece can also be used for daytime observations, and of course with a 90° star diagonal it is more comfortable during the night.


1.  I know they exists some very expensive astro-quality 90° erecting prism, but I do not know of very good quality 45° erecting prisms which can be used with a telescope. The risk of losing optical quality in daytime is there.

2. A telescope is less robust, heavier and not waterproof. For daytime use those are important weakness.

  • Castor, Crusty99 and MennoB like this


Quick and easy spotting scope can be a friend to those who like grab-n-go. Also an easy to set up--and comfortable--observing chair.

    • paulsky and Castor like this

I'll second how unbalanced the 65mm Regals are. They didn't scale down the back end with the prisims. I have an 80mm and the part from the rotation ring backwards is exactly the same and it makes for a terribly unbalanced scope. 


Typical Celestron, great optics, so-so build quality & design.  The 80mm is much better proportioned, but I have found image shift when focusing on the moon. I don't think the focusing elements are properly supported as they move through their travel. For the money they are decent enough. 


I use mine mostly at the shooting range and for that they excel. 


    • Castor likes this

I have the 100mm. It's also a nice scope, but not balanced any better. As here, a long Arca plate solves the problem. (Celestron includes a long foot adapter, but it's crude and heavy.) Otherwise the build quality is nice, and it's sharp with little fringing. I probably won't risk it in really tough conditions, but the build quality and weatherproofing seem pretty robust.


My only real disappointment is that eyepiece projection using the included t-adapter on the stock eyepiece is pretty terrible. I'm not sure why they bother. Afocal digiscoping works ok, and that seems to be the only option. There isn't enough travel to reach prime focus (except maybe with a Barlow as relay, which I haven't tried).


I mostly use it for terrestrial wildlife, but it's a lot better for astro than I expected. It only suffers from lack of a good way to mount a finder of some sort.

    • paulsky and Castor like this

I can honestly say that I have never had a problem with using my spotting scope for a quick spot of random astronomy. I have even taken it on holiday and been very impressed with the views. I own better more suited scopes and mounts. But the cheap Acuter I own has been a handy friend when my wife's packing leaves little room for my astronomy gear.


Great review mate. ;-)

    • Castor likes this
Oct 19 2019 01:02 PM

IMHO...spotting scopes are built mostly for terrain uses, and as the subject starter has recognized, the position of the eye piece at 45 degrees does not lend itself readily for a comfortable position for observing the heavens.

But remember, you use what you have, and make do.

If that is your go to travel scope, and are willing to put up with it's idiosyncrasy's, who can say differently.

Putting another 45 degree angle diagonal on it would solve that problem, two 45's make a 90 if I remember my grade school math.

Enjoy the Universe in your own time, with the equipment that's available to you, and make do.

Clear Skies.


Excellent review Riccardo! waytogo.gif


Although I use my spotting scopes mostly for terrestrial viewing, when I travel to the great outdoors for doing Astronomy, my 80mm ED spotting scope is the instrument of choice.  No worries about tedious setup or tear down, dust, sand, ashes, fog, drizzle, rain or internal condensation caused by abrupt temperature changes, just setup the scope on a photo tripod and enjoy!

I've had fun with my Pentax PF-80ED Angled scope on camping trips. Like the Celestron in this review, it takes 1.25" eyepieces and doesn't seem to suffer CA too badly. Since there is no practical way to attach a finder, I find myself using the Pentax 20-60x zoom eyepiece--starting wide field and magnifying as needed. I also use a Celeston 20mm eyepiece quite a bit. I believe the focal length of my scope is 520mm. 


Wondering if anyone here has tried one of the iOptron EQ motors with these types of scopes. I have a Pentax T-mount, and K-5 SLR, and want to try some astrophotography with it.


I most recently purchased a Kowa TSN-553 with a fluorite lens. I haven't tried looking at the night sky with it yet. It was pretty expensive--for a 55mm objective. A bit of guilt, but it's really light and bright for mountain viewing near my home.

Hi Brian, welcome to Cloudy Nights!


Hey, we have exactly the same scope, the PF-80ED-A, I love using mine for both terrestrial and astronomical observing!  Yes, there is no easy way to add a finder to a spotting scope, but where there’s a will there’s a way and I found one, maybe not very classy but still decent looking and very functional.  After I added a mounting block to my scope (using zip ties) with a rail compatible with small, light (plastic) red dot finders, I even get to choose my favorite RDF model for day or night applications.  Here is a link to my post where I describe the parts that were needed and show pictures of the outcome.  Since I added a RDF to my Pentax spotting scope, aiming it at the night sky is quite effortless and intuitive!




    • bmurphy495 likes this

Thanks for the welcome--and the link to your scope/finder.  I like it!


Any thoughts on attaching it to the mount below--with a ball head and camera?



    • Castor likes this

Thanks for the welcome--and the link to your scope/finder.  I like it!


Any thoughts on attaching it to the mount below--with a ball head and camera?



Thank you Brian!


I’m afraid I have no experience using spotting scopes on any mount other than fluid video heads set on photo tripods, I’m sorry that I can’t offer any useful input about your question.

"...It only suffers from lack of a good way to mount a finder of some sort."

I just ordered a Baader Sky Surfer III Red Dot Finder for the Celestron Regal M2 100mm based off the pictured ability to place the RDF on the mount (the Regal is actually pictured with installation on Amazon when you click on the photos). I've got a Stellarvue RDF setup right now that took modifications to mount, but if the pics of the baader are accurate, this might be my solution.


Re: spotting scopes for astronomy--I use a BH-MKIV zoom in the Regal 100mm and it's good for astronomy. I see planetary detail on Jupiter and Saturn on this setup that I really enjoy. During the day I can spot deer or red bellied woodpeckers in fantastic detail and color from great distances and I've changed nothing to go from one hobby to the other. It gets use all day and night around my house. I'm not saying it's the "ultimate" minimalist setup for astronomy and naturalism, but I fail to see it as a bad option for either hobby.


The waterproofing is key for bad weather terrestrial viewing that isn't usually a problem for astronomy, and I take it hiking/kayaking etc so it needs to be able to take a beating without putting me several thousand dollars out when it breaks and I'm not sure how many telescopes are built for that (or that would be affordable enough with good views that wouldn't make me cry if they were damaged). 


Interestingly (and I contacted Baader about this) I am able to use the Hyperion 2.25x Barlow within the Regal/Mark IV setup and maintain massive terrestrial magnifications that maintain great views (but do fade towards 3.5mm). I underlined "terrestrial" above, because using the BH-MKIV+Barlow on celestial objects does not work in the Regal, but I kept the barlow just because of what it can do for me pointed at earth. Not a plus for astronomy, but screwing a barlow onto an EP and sliding it into a lock ring in ten seconds for terrestrial views and then quickly popping it off for astronomy is very convenient and packs very small for massive terrestrial magnifications.


I honestly don't have issues with the 45deg EP. I can get it to zenith with a quick tripod adjustment and low seating in a matter of seconds and it doesn't involve any neck pain. Maybe it's my seating and tripod setup, but I have no complaints with it.

    • paulsky and Castor like this

FYI, I've now used the Meade 5.5 UWA 82o in the Celestron Regal M2 100 spotting scope. The best view I've had of Saturn through the scope. The eyepiece doesn't fit well into the lock ring system--it takes more force than some might be comfortable with to get it in. It's also a waterproof piece, so that can be a plus for those trekking and using it for terrestrial view. 


I then purchased a TV 3-6mm Zoom to see what it can do in the Regal. No clear nights yet, but terrestrial views are very good. No issues with this piece getting into the lock ring system. I don't yet know if it will focus to objects at infinity, but I'm optimistic in it working with the scope since the 5.5mm UWA worked very well and BHMK-IV + Barlow experiment failed for the sky (but not terra).


I was interested in taking this further and was inspired by some of the setups and abilities to push certain spotting scopes in previous threads on here, so I will be experimenting with the Kowa TSN-883 + TSN-EX1.6x + TE-11 Zoom, and looking for extremely clear nights where it may be possible to use the TV 3-6 on it's own, or even the TSN-EX1.6x with the TV 3-6mm and 1.25" adapter to go 133x-267x based off previous reports that the Kowa might succeed at as much as 270x. 


I absolutely realize, as was exhaustively fleshed out in the now closed discussion on this, that an astronomical telescope might very well do better at terrestrial and celestial viewing than the rig I'm setting up. Cost also has to be factored. But the total weight of this rig will be 6.9lbs. Waterproof. With a 16" length. And with high quality lenses. If you are kayaking to locations, hiking, in rough weather situations, etc this seems like an extremely light setup (weight cannot be understated in packing situations) that affords you the ability to get magnifications you may not be able to otherwise at these locations. 


I also keep reading the complaints about the 45o angle as being a major issue for folks, and I'm genuinely asking about this issue out of ignorance, because my Regal tripod will raise to 69" fully extended and allows me to stand and point straight to zenith with no discomfort and no viewing positions (standing) result in me having neck problems or posture issues. Certainly observer-dependent with my height being ideal for that mount height, but nonetheless, there seem to be tripods (the Manfrotto with Q90 center column I have coming to experiment with being one of them) that could potentially eliminate the 45 angle being a problem. If all this fails to provide a lightweight, waterproof, exceptional viewing for both terrestrial and celestial observing that suits a particular niche of observer, I would be very surprised, but would also humbly re-think based off the data it provides. 


I understand this is mainly about strictly astronomy-based viewing on here, but I was led to this forum based off trying to thoroughly research how I could marry hobbies of astronomy, outdoor adventuring, and naturalistic observation in the most minimalist package with the best possible views, in the lightest package, and under the most weather/terrain conditions and I think there's no harm in providing additional data and discussion on that whatsoever. 

    • paulsky and Castor like this
I used 50mm 20x yukon for my first astronomical observations. It was ok
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"...I then purchased a TV 3-6mm Zoom to see what it can do in the Regal. No clear nights yet, but terrestrial views are very good. No issues with this piece getting into the lock ring system. I don't yet know if it will focus to objects at infinity, but I'm optimistic..."






Following up on this, the Tele Vue 3-6mm would not focus to infinity on the Celestron Regal M2 100ED. I debated on using the TV 3-6mm in the Kowa TSN-883 with the astro-adapter, but I found the Kowa 1.6x extenders at a fantastic price over in Europe so now I'm going to see what the Kowa can do with 3 stacked extenders pointed at Saturn and Jupiter. I've already looked through it for terrestrial views with 1,2 & 3 extenders, and this scope is something special. Granted, my experience is low amongst high quality optics, but other than the first time I hit the image stabilizer on my canon binocs, I've not had a wow moment like I had with the Kowa last night.

    • Castor likes this

Had about 5 minutes where the sky opened up for Jupiter and Saturn last night with the Kowa TSN-883. With 3 Kowa 1.6x extenders, I calculated the highest magnification with the TE-11 Zoom to be around 246x but someone feel free to correct me on that (assuming 500mm focal length). Maybe a Bortle 7 or 8 night? Certainly the best views of these two planets I've ever experienced through a scope. 

    • Castor likes this

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