The Orion XT4.5, is, by Orion's own description, a telescope for kids. But since Orion has made their name by providing real telescopes, this isn't just a toy which looks like a telescope and has very little capability; it's a real telescope. But to make it more kid sized, the mount is reduced to a scale friendlier to kids. I have more general information on telescopes in my article on
Picking a Telescope.
Background About five minutes looking at online auctions will show there are mountains of fairly lousy pieces of junk masquerading as "Children's telescopes." These range from 60mm refractors with absurd labels like "600X" telescope to poorly made Newtonians which are barely functional. These are telescopes built to disappoint and leave the impression there isn't much to be seen in the night sky.
The Key Question is: What makes an appropriate and effective children's telescope? The funny thing is, as obvious as the question is, I don't remember ever hearing of it taken seriously, so I will take a crack at an answer.
(A) A child's telescope must produce an image good enough to see craters on the moon, the rings of Saturn, and the moons and stripes on Jupiter. It should also be able to produce a good image of the Pleiades, Orion Nebula, and Double Cluster. These are some of the best objects in the sky, so if it can't do a good job on them, there's no point in bringing it home.
(B) A children's telescope needs to be relatively inexpensive. Kids experiment, and it may be destroyed in the process. And it is hard to tell if they will get into the hobby, so a little trepidation on the part of a parent is fair.
(C) It needs to be simple to operate. The obvious things you see up above deserve a look. That should be easy to do. Do you really need a computer control system to find the moon or what looks like the brightest star in the sky?
(D) It needs to be rugged enough to be successful.
(E) It should have potential to grow with the young observer. If there is some success with the first objects, the curious only need to do a quick search to find more things to look at. It would be good to be able to get into that list before the telescope's capability was exhausted.
In an act which can only be called singularly rare, Orion took the question of a children's telescope seriously and designed something to try and do this trick based on their outstanding line of XT series telescopes, including the
XT6,
XT8, and
XT10.
Description and Usage The XT4.5 is a sort of an odd hybrid because it takes the layout of a Dobsonian, which is nominally intended to give the user the largest diameter telescope in a given package, with a minimal push-mount to support it. In this case, the goal has been to minimize the telescope to the point where it could be used by a child around seven years old.
The Orion Dobsonian telescopes are all steel-tubed Newtonian optical tubes mounted on a laminated plywood stand. The mount has Teflon pads and a very smooth three-footed turntable. To make the telescope more stable, it has a set of tensioning springs which pull the telescope against the Teflon bearing pads. Teflon has an unusual property where its sliding friction and starting friction are about the same. As a result, something sliding on a Teflon pad will not jump when it starts. Since the XT4.5's optical tube is relatively short, the balance problem isn't as serious as on larger telescopes, and since few 7 year olds will be using heavy $300 Tele Vue eyepieces, this should never be a problem.
The Orion XT4.5 is very compact telescope with a small barrel which moves very easily- when going to objects, you take the tube and just push it the way you want it to go, and it will move there. After an object is in the field of view, gently nudging the tube is all that is needed to keep it centered. A drawer-pull sized knob near the front end to gives the user something to hold on to for moving the telescope (easier that trying to grab the barrel over and over). My main complaint on this feature is it is black, so it doesn't show up at night- it should be white so it would be visible in starlight. The tube will stop when you stop pushing, and it is easy to make fine corrections. This is literally a telescope where you can walk outside, set it down, and just point it at something immediately. Unlike a Go-to telescope, there is no setup or slewing to wait for. And especially unlike an equatorial mount, there is no 45 minute tedious polar alignment procedure (when you have been observing for a while, but not something a 7 year old will think of as fun).
The small stature of the XT4.5 means weight savings; it is about half the weight of the larger XT6, and when at the zenith has its eyepiece about 38" off the ground. At this location, fairly young children are able to use it, but it is a very low for an adult. But it also comes with a set of handles on the optical tube and stand to make it possible to pick it up and carry it, which is relatively easy for an adult (especially an adult who has been putting on upper body strength picking up kids recently).
The optics are actually surprisingly decent for what is advertised as a children's telescope. It has a 910 mm focal length which means the Orion Nebula, Pleiades, and double cluster have no trouble fitting into a field of view. But the better treat is it is able to go up to enough magnification to show the rings of Saturn with enough detail to show the Cassini division, and cleanly split double stars like the double double. This is a result of its f/8 optical prescription, which is fairly good for a general purpose telescope. This does give it some limits for getting into seeing dimmer objects, but with that said, it is a reasonable for a children's telescope for use in back yards more, where brighter objects are the most obvious viewing targets.
Keep in mind, objects like Mars and the Ring Nebula are going to be really small in this telescope, and that is just the way it is, even with telescope considerably larger than this one. But for me, the bigger limitation has ended up being the kid-sized mount. This means an adult in a normal size range would need to kneel to be able to see through the XT4.5 and using its finder scope is nearly impossible. This is a major difficulty for a longer observing session, since the child ends up being the only person who
can stick with using the XT4.5, or it has to be set up on an elevated surface for an adult, and then loses its ability to be a kid's scope. As a result, being able to look and see things a child is happy about having found on their own means bending fairly low, especially if it is something away from the zenith.
So, while the performance of the optical tube is good, the low mount makes observing sessions awkward, and does mean the telescope is destined to literally get outgrown. And, at that point, while the other XT series telescopes appear to be showing wear performance which would indicate they are able to survive many years of use, the XT4.5 seems assured to end up in idle storage, like an old tricycle. At the same time, the low height makes setup more complicated since simple tasks like getting the finder scope aligned with the main optical tube require being able to get behind it, which is at a height similar to looking under a table with this scope, so it means you set the scope on a table to get it align its finder scope or collimate it, so it really isn't a stand-alone kid's scope. It is possible it could be set on a low bench or up on blocks to make it friendlier to taller people, but that isn't a very convenient work-around. In comparison, the XT6 is only $30 more, and comes with a laser collimator to boot, making it a much better value besides its improved performance, and a child could just use a small step if the eyepiece was too high.
Another telescope which makes a good candidate for a rugged kid's telescope is the
Short Tube 80. In terms of the cost, it is not far from the XT4.5, but it is a telescope which never needs adjustment, is very compact, can be used for day or night observing, and can easily migrate to different mounts over time.
The reason the outgrown telescope issue bothers me is it means the first interest in astronomy this telescope may kindle is a dead end with this telescope. With something like the Short Tube 80, it can be set aside for a while and resumed later, and it could even be used right into adulthood. And as a parent, I like the idea of giving children things which don't have to stay behind when they grow up.
Conclusion For a telescope specifically sold as a children's telescope, the XT4.5 stands out as having real optical performance. My main complaints with this telescope come from its small size, which while appropriate for a young child, means it is very difficult for an adult to use, and more importantly, mean the child will outgrow it. At the same time, this telescope costs within $30 of the XT6, which doesn't have these limitations, and is close to the cost of other alternatives such as an 80mm refractor which don't have these restrictions.
