Meade ETX-125

The ETX-125 is my second GOTO scope, mainly bought for it's 5” aperture. To no time ever I regretted yet that I've spent quiet an amount of money for it. The telescope came with a 26mm Super-Plössl (the common standard these days), the deluxe field tripod (this is the sturdy version of the ETX tripods), the #497 Autostar hand-controller and a filter of choice (I selected a Nd-skyglow). The final push to the decision was triggered by Meade's eyepiece special (a case with seven Series 4000 Super Plössls) for the 30th birthday of the company.

Autostar drive training is essential to obtain max goto fun. At least at first sight. Daytime work! Proper training minimizes the “rubber band” problem reported by many ETX users. This, btw, is common to all ETX telescopes, e.g. the ETX-70 with the #494 Autostar hand-controller.
Concerning Autostar, a RS-232 cable was quickly built, enabling firmware updates of the controller. For obvious reasons a patched update was uploaded which enables editing drive train values... With trial and error good results can be achieved this way in much less time than the traditional training procedure takes.
The tracking is very good, compared to a telescope of a competitor of Meade I happen to own too. Not perfect though... with short focal length EPs (high power, as some would say) the tracked object drifts back and forth in the FOV; the average pointing position remains on the objects to be tracked.

The optical performance of the telescope is very very satisfying, at least what my needs are concerned. Primarily one might think that the f/15 instrument mainly serves planetary observations with delivering a view too dark for deep sky objects.
In fact, planets are a pleasure to look at through the ETX-125. For Jupiter and Saturn my preferred eyepiece is the 12.4mm Super-Plössl, seeing in my place does usually not allow for greater magnifications. All sorts of rings, divisions, bands, belts and moons are nicely visible with very good contrast (w/o any filters). Mars was nice, during the opposition in 2003. When reaching around on my page you will realize that planets are not my main hobby.
So, what's about deep sky then? Believe it or not, the 5” f/5 are really performing nicely, at least when used on star cluster. For objects like M35, M36, M37, M38, NGC869 and NGC884 (just to mention a few), the 32mm Super Plössl appears to be ideal. All these cluster fit quiet well in the FOV of this setup.
Globulars, such as M3, M13 and M15, reveal a lot of detail in higher power eyepieces.
Galaxies... well... would be nice to see more of these than just the core, but living in one of Europe's strongest light-polluted places I can hot hope for much, at least in respect to the visual channel.
I have not yet checked on planetary nebulae, I guess the brighter ones will be observed without problems...
Conclusion: Bright(er) DSOs are no problem for the ETX-125 at all, with an excellent performance on planets, the 5” ETX is a real all purpose instrument.

Now, are there downsides? Yes, there are!
The clutches feel strange. For the azimuth clutch (α in equatorial mode) there is a simple solution, same as with the ETX-70 , the lever hex-nut can be set to softer operation. The altitude (δ in equatorial mode) clutch does not allow for a quick fix like this... Simply, it will always feel strange, in a way...
The handling of the telescope is not ideal. The whole setup is relatively heavy (and bulky), which, I guess, is normal to larger aperture Maksutov-Cassegrainians. Personally I can still carry the scope mounted on the tripod with one arm, but it's not comfortable to do so anymore.
Free flowing of the hand-box... is that really necessary? Competitors (all of them) came up with pretty ideas to hold the control-box next to the telescope or, at least, provided a long enough cable. Well, there is, speaking of a longer cable, a work-around, click here!
Common to all ETXs I've seen up to now, slewing is rather noisy (like a coffee grinder a full duty). Tracking is conveniently quiet...

A comparison between the ETX-125 and the 8” f/5 Newtonian, with roughly identical FOVs, revealed a surprisingly positive result for the 5” Maksutov. The background (and the allover appearance) is much darker in the Maksutov, regarding the smaller aperture and the quiet different focal ratio this is not a real surprise. Certainly there were less stars visible in the 5” than in the 8” when viewing fainter open clusters. Still, the impressions on all these clusters were impressive in the 5”.
Up to now I was too lazy to compare visible magnitudes... “stay tuned”, maybe I'll do that sometime...

Strange thing on the ETX-Maksutovs, both, the ETX-125 as well as the ETX-90 appear to be dust magnets. Compared to the ETX-70 refractor telescope, I did not use the Maks at all... if you know what I mean, the corrector plates of both Maksutovs are covered by a rather visible layer of what ever, whilst the Fraunhofer still is nice and shiny. All scopes were used with dew-shields and were closed when warmed up and dry. Any ideas?


Last modified Feb. 28th 2005