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Orion Skywatcher 120mm

I have about four years of total observing experience. My first telescope was a cheap starter 60mm refractor. I also observe frequently with a decent pair of 10x50 binoculars.

The Telescope and Accessories

About five months ago I ordered the Orion Skywatcher 120mm from Orion's web page. It arrived promptly within five business days and neatly packed and undamaged. Included with this scope is the mount a EQ - 3 (which is really a CG4), a polar alignment scope, 6x30mm finder, and two eyepieces (10mm and 25mm plossel).

With very little experience with real telescopes I was amazed by the sheer size of the scope and mount. I was also impressed with the quality of the construction, not only of the scope but of all of the accessories. I was also impressed with the quality looking coatings on the objective lens.

On top of the normal accessories I had also purchased a 40mm Sirius plossel and 7.5mm Ultrascopic eyepiece. Both of which came promptly and undamaged. Lastly I purchased an Ultrascopic Barlow which took almost two full months to arrive. On top of this it seems that this telescope is entirely incapable of working with this Barlow. After some troubleshooting with Orion they also agreed that this Barlow just won't work with the telescope and allowed me to return it almost three months after the purchase. I must mention that Orion has excellent customer service and they were more than willing to bend their return policy rules to help me. In the end I exchanged for a shorty Barlow also from Orion.

Location and First Light

First off I must mention that my review will be skewed by the fact that I live in a very heavily populated area of West Michigan that not only suffers from many cloudy nights but a limiting magnitude of a little over 3-3.5 on a decent night. I live about five miles from downtown Grand Rapids and my view to the east is almost entirely limited to lunar and planetary viewing. This was one major reason that I had decided to get a refractor as opposed to a much larger reflecting telescope.
The first day it took me about an hour to fully assemble the scope and then another fifteen minutes for setup that night. Luckily for me Orion was in the darkest portion of my night sky for first light. My first target was the heart of the Orion nebula and the trapezium. The four stars were easily split with the 25mm plossel (40x). The best views however were through the 40mm Sirius plossel (25x). With this eyepiece in place the whole view had a ghostly pale glow. I than spent the next few hours slowly scanning the spring sky with the 40mm plossel. This telescope has excellent optics for the price. Stars are sharp across almost the entire FOV, and this is with a 40mm eyepiece.

Jupiter, Saturn, and Moon

A few nights later I had the chance to catch Jupiter and Saturn before they set in the western sky. My first target was Jupiter which I have spent much time on with my old telescope. This was completely different. At 25x the planet and moons took their familiar shape while at 100x with the 10mm plossel the disk was plainly visible with pastel banding visible. Taking it up to 133x with the Ultrascopic showed much of the same with slightly higher contrast. Being limited to 133x I was looking forward to getting my Barlow (sadly I did not receive a working Balow until well after Saturn and Jupiter had set in the west). The views of Saturn were similarly awe inspiring but once again my lack of power has me waiting on edge to catch both of these planets in the coming months. The view of Saturn was limited to a very small view of the disk and rings. Oddly enough some people (non astronomers) I had over at the time were more excited about the view of Saturn than the much more detailed view of Jupiter.

I have however had plenty of time to observe the moon both pre and post Barlow. This telescope has helped to make the moon probably my favorite target. All of me eyepieces show extremely high contrast sharp views of the moon. The full moon fills the entire FOV with in the 25mm plossel (40x). I have even on a few occasions been able to catch more than a few craters on the floor of Plato with the Ultrascopic eyepiece.

Deep Sky

When I purchased this telescope my previous experience with deep sky observing had been basically limited to the Andromeda Galaxy. With this telescope I have been able to observe a great multitude of nebula, clusters, and a few galaxies. A few of the best views have come from the great globular clusters. M13 is absolutely spectacular showing up like a large glittering ball of light in all of my eyepieces. This telescope seems to excel at delivering high contrast images of deep space. Considering where I live I have been more than satisfied with the deep sky views. Initially I was concerned whether I would even be able to see anything but even faint deep sky wonders are easy to find. A few of my other favorites in this scope are M57 (surprisingly I caught it in the eastern sky), M27 (also in the bright eastern sky), M4, and the entire Scorpius - Saggitarius region.

A few Negatives

There are a few downsides to this telescope. First of all the mount is on the light side and is probably going to be the first thing to be upgraded. Vibrations really intrude at high powers and small gusts of wind can ruin an otherwise perfect observing session. Also false color can be an issue. Although not very apparent on the moon it does show particularly on Jupiter and on a few of the very brightest stars. However it is not as bad as I thought it would be for an achromatic refractor at f 8.3. It is also my personal opinion that it really does not matter that much, at least it does not bother me as much as some people but the amount of color does not justify spending $2000 more dollars for visual observing.


All in all this telescope has been an excellent piece of equipment. It has met and exceeded almost all of my expectations. Considering where I live I have also been extremely impressed with the deep sky views of the Summer milky way. I would recommend this scope to anyone looking for a good low priced refractor. I also recommend Orion Telescopes mainly for their excellent customer service and tech support departments.

Addendum 11/14/00

The Diagonal

As a word of warning for the owners of this scope I am posting an update dealing with an issue I found with the supplied diagonal. While doing some routine maintenance of my scope I decided to clean the mirror on my diagonal. After carefully taking the diagonal apart I quickly noticed that the mirror was mounted seriously out of alignment. After taking time to reflect on the situation I realized that my view of the scope was probably skewed by the fact that my diagonal was defective.

The Remedy

Simple. I took a couple quick digital pictures of the diagonal and sent them to Orion. Within hours I had already received a reply that they were sending me a new mirror diagonal (slight upgrade) from their catalog as soon as possible. Once again I must mention that Orion has excellent customer service. I don't know of many companies that would voluntarily send a replacement item no questions asked almost six months after I had made the purchase.

The New Diagonal

The replacement that I received came within three business days and was undamaged. It is their standard 1½-inch mirror star diagonal found in their catalog. It is my belief that this is probably a slight upgrade from the original unit that shipped with my scope.

WOW! Everything looks much sharper. Stars are a little tighter, the moon seems a bit brighter, and the planets are magnificent. I feel as if my telescope is finally really performing at or near its maximum potential.

Moon and Planets

For the first time since the purchase of my scope I have a really clear shot at Jupiter and Saturn. This scope is really living up to the classic refractor expectations on the planets. The views of Jupiter are almost photo quality during good seeing. I have pushed the scope to 250x comfortably on Jupiter before the mount begins to get in the way.

Personally I like the view at 100x better as the banding is much sharper (although the view is small), the contrast is extremely high, and the major moons fit neatly in the FOV. At moderate powers the disk shows great detail with many bands visible and on one recent occasion a very faint view of the GRS. Jupiter by far has become one of my top five targets since purchasing this scope.

Saturn, what can I say? The views are absolutely stunning. Even at low powers (under 100x) the detail is hard to believe. The rings are clearly visible along with the moons and the dusty colored disk of the planet.

Increasing the power yields major improvements in the detail especially in the rings and on the disk itself. Banding easily becomes evident at around 200x as well as the major ring division. In my opinion Saturn tends to hold up at higher powers better than even Jupiter as I have pushed this scope near 300x with great results. Take in mind that at 300x focusing becomes a real test of patience with the shaky mount.

The moon surprisingly has seen the smallest amount of improvement since the replacement of the diagonal. I guess I could say that the view is slightly sharper but not much. Even with the bad diagonal I could catch a few craters in Plato on good nights. It seems that I am still seeing the same small craters with the new diagonal. In other words there has not been a major improvement.

It does seem however that star images and in turn some of the more local deep sky objects (clusters mainly) have improved in terms of contrast and sharpness. Star images are now tack sharp almost to the edge of the FOV, this also lends to the fact that clusters are a touch more pleasant to look at. As far as the rest of the deep sky is concerned, I have not really seen much difference. Granted I am looking into mag. 4.0 skies at the best.


In retrospect I firmly believe that this telescope is clearly worth the money I spent on it. True, the diagonal was a small hassle but overall I have been very pleased with the performance of this scope. I would simply urge anyone out there who currently owns this scope to take a serious look at the diagonal and press Orion for a return if it is defective. On the other hand I do not believe that this should prevent anyone from buying this telescope. Just be careful and inspect your purchase. Most of all trust the fact that Orion is dedicated to customer service and they will try their hardest to correct any problems that you may run into.


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