Celestron Nexstar 127 SLT - Review

[sticks]

I bought the Celestron MAK 127 a few weeks ago and I thought it might be helpful to review the scope as I now feel confident that I understand it and no longer feel such a newbie.

Assembly is a doddle. The mount and tripod come ready assembled and all the bits were present and correct. Attaching the OTA to the mount is easy enough but you need to be careful to make sure that the scope is slid into the mounting and pushed against the shoe before tightening the bolt. On one occasion I got it wrong and the scope nearly fell out of the mount. Could have been nasty.

Next was setting up the red dot finder. Not a nice piece of kit this really, I find it a bit hit and miss to be honest, and if the scope didn’t have go-to, I would change it for a Rigel Quickfinder. The other thing about the RDF is that you tend to be on your knees most of the time when using it due to its location at the EP end of the tube. But with go-to you tend to use the RDF for alignment purposes mostly so it becomes less of an issue as your expertise improves.

After a good read of the manual (honest) I had first try at alignment. I guess I was in too much of a hurry. You really do have to do this one step at a time, with care and patience. It is easy to hit the wrong button and foul the whole process up, particularly if like me, you wear reading glasses and they are on and off your head the whole time while you repeatedly read the handset and then look through the EP.

Note that the slewing speed alters between the first stage alignment with the RDF and the final alignment through the EP. This can be disconcerting as the whole movement slows up dramatically and I thought the scope was busted at first. The learning curve is steep initially but a couple of sessions sees a marked improvement in your ability. I can now get the scope assembled and aligned in less than 10 minutes.

I feet the manual could be clearer and more helpful, but posts on the Forum here helped a lot with getting my head around it. You do have to make sure the scope is level and that lat’ and long’ and time are as accurate as possible. There are apps for the iphone/ipod which help with this . One is called “clock” which gives the time down to seconds and the other is “geoquick” which gives accurate lat’ and long’ for your location.

At this point I should mention the need for some accessories that I have found to be essential. A dew shield, a power tank to remove any reliance on AA batteries, a case to protect the OTA, handset and optical bits when not assembled and better EPs really do make a massive difference to the scope’s performance. I spent about £300 on accessories............. for a £370 scope! Repeat, better EPs really do make a massive difference to the scope’s performance.

So what is observing like? Frankly it is brilliant and far exceeds my expectations. Early targets like Jupiter and the Moon totally blew me away. Objects like the Andromeda galaxy and the Orion nebula are simply amazing when you realise what you’re seeing – now, and from your own back yard, not in a book or on the telly. OK they’re not seen like astro-photographs but they are beautiful and they’re “live”.

The go-to really comes into its own when you dig into the software. I find features like the constellation tour an amazing assistance and time saver. With the poor seeing I have here I could never locate many of these things by star-hopping - a dob’ would be a waste of time at my place. The constellation feature compliments the approach taken in most astro books where suggested observations are set out on the same basis.

Now that I have got alignment sussed I find the targets I choose are always in the FOV of the 25mm BST I use for searching. I can then centre them and use a higher power EP if appropriate. Another fine adjustment will bring the object dead centre and then the tracking takes over. I love the tracking, it is so effective, particularly when you are sharing the scope with other observers.

I can hear you saying “there must be weaknesses” and you’re right. The tripod is a bit shaky and, while adding ballast to the accessory tray helps a lot, windy conditions can be troublesome. I am thinking of investing in the Celestron suppression pads, but at £48, thinking is as far as I have got....

I am also a little dubious about the star diagonal. It looks and feels cheap and EPs with filters on could scratch the mirrors. So that’s another £65 for a better diagonal -one day perhaps!

I read in some posts that the limited FOV of the scope at 1* is a bit limiting for DSOs but I haven’t really come up against that yet. I suppose I have so much to look at I’m a bit spoilt for choice at present and targets larger than the FOV aren’t a frustration – for now....

Perhaps the best feature of this scope, outside its quality views and operation, is portability. I need to travel to darker sites and the whole setup is very compact and light and can be moved easily taking up little space in the car.

So there you have it. I am very pleased indeed with my MAK 127 and have joined the community of users who extol the virtues of this little scope. It may be a budget item but it sure plays above its game.

[hemihaggis]

best scope i ever had , wish i had not sold it

[SilverSeadog]

Thanks for the review. I'm a newbie with a Nexstar 127 SLT so I've only just got round to seeing your post! It was most encouraging as I am having a few 'issues'. But Im sure now that, with a bit of patience, I'll be OK. Thanks again.

[ccbmedic]

I think the OTA itself is nice and easy to use, however the focus knob isnt very much to be desired, touch it and watch your image shift and wobble like a jelly. The only way to solve this is to either fit an electric focuser, make a larger knob which is what Ive done for now or upgrade to a sct 10:1 focuser as some people have done.

The mount is a complete waste of time, adding extra weight helps a little as previously pointed out but by no means a solution. In short get rid of the mount and get something sturdy at least an eq5 or alternatively find an OTA only and save some pennies in the process to then put towards a better mount.

Buying an all in one kit at the beginners end of the line is a little bit of a false economy, when you first get it your excited and love it but with prolonged use (if the clouds do one) you will come to realise that you will need to upgrade pretty much straight away. The mount for sure as too the diagonal and bundled eyepieces are a complete waste of space.

Once you have done your upgrades you will realise what a little gem this scope is, I really do enjoy using mine but feel for all the people falling into the same trap that I did when I initially got mine.

All in all, A great little OTA bundled with a poor mount and poor ancils.

[Donkeiller]

Yes the mount is shaky out of the box.

Tighten up all screws

Superglue joints that can remain "fixed"

Never extend lower legs nore than 20 cm

Lower the centre tray by 10 cm.

Place a weight (I use a 17AH lead-acid battery) on the centre tray.

Then you have quite a nice mount.

[tjr]

Great write up of an amazing little scope. You're right about the eyepieces, investing in a few good quality ones make observing with these makes a real pleasure.

[murphy]

I have also recently bought one of these as an upgrade from the 80mm spotter I was using previously. Much better views. It's just a shame they were out of stock so long that I missed the great views of Jupiter I was getting earlier in the year.

The light pollution is so bad at my place, with numerous tall street lights out the front and shorter ones one the slope above the back that deep sky viewing is more or less impossible. Not to mention the security lights on the two next door houses.

It's almost like Wembley stadium at night!

I'm considering upgrading the focuser by adding a helical focuser to the back but finding an adapter that definitely fits is a problem as by all accounts it's different from the skywatcher mak back. I thought about adding the helical focuser to the t threaded part at the back but then the diagonal would move unless I source a non rotating version.

I almost went for the smaller C version mak and only wish the mount could take the weight of a C5 or C6 so I could upgrade to one of them without spending a fortune for a GOTO mount.

Some more eyepieces and maybe a better diagonal as well are next on my list as well.

I tightened the bolt behind the dovetail mount holder to try to stop the scope slipping but it doesn't seem to have helped much as the altitude still moves by hand fairly easily, more so with the heavier Hyperion eyepiece I added.

The finder hasn't bothered my that much and I had no trouble aligning it but I agree it can be awkward to look through at higher alt settings and it doesn't keep alignment between viewing sessions very well so I swapped it for a 6x30 finder that FLO were selling cheaply.

[lucas1860]

Hello, new to this site. I have purchased the 127 SLT, (22 Nov 2012) to say I've had enough of it is a joke. The Nexstar+ handset has been a pain, for a device straight out of the box its rubbish. 2 handset now, the 1st with a boot loader error message 0002, the 2nd handset with the same message but with the code 0050. My seller states that its not a problem he has heard of yet no most sites about this handset they all state you have to upgrade the handset.....all good but at further expense, poor customer experience on this one.

[Baffa]

About the varying slew speeds - mine did that before of the motors died, might be good idea to see if there is something hindering, too much friction or something else because I don't think it should vary Alot.