A Beginner's Telescope

As an astronomy outreach community we get an inquiry almost every week asking about what's a good starting telescope (mostly parents asking for their kids). It thrills us when we see people interested in purchasing their first telescope to marvel at the beauty of the night skies, and of course hopeful that they will share the views with others. There are a lot of telescopes out there and not all of them may be suitable for a beginner or your budget, so we'll try to point out what you should look for in a telescope to make it a worthwhile investment.

Here's the thing – telescopes are scientific instruments. If you're only thinking of casual observing then your natural tendency is to stay away from pricey telescopes. And who wouldn't?! Telescopes are really expensive! Even members of the local astronomical community have to search every time we think of purchasing new equipment. However the cost of telescopes can tell you something about your purchase – quality. You might see those telescopes online that cost less than Php 3,000 but they really have a lot of issues (some of them are more of toy telescopes).

The most important issue is the optics – they have to be perfect. If the optics are problematic, then you'll end up with a lot of aberrations (image defects) when you look at objects. I've had one occasion where a parent asked me to get their telescope to work and the optics were terrible that it couldn't even get a clear view of the Moon (note: The Moon is big and bright enough that even SOME toy telescopes can produce a clear view). Also using telescopes with poor optics can strain your eyes. The curvature on the lenses and mirrors have to be perfect otherwise the light rays that enter your telescope will not be focused at the same point. Lenses from eyepieces and refracting telescopes have to be perfect for light to pass through without being refracted in all the wrong angles. While some plastic lenses today can be manufactured with good optical quality, there are still a large number of poorly manufactured lenses. You can try and see for yourself in some of the magnifying lenses that are commercially available that there is some distortion in the image produced. These cheap plastic lenses are those that usually go with those low-priced telescopes.

Another thing to look out for is the mount. A telescope has to be stable in order for you to enjoy your view, and sometimes even the good telescopes can come with terrible mounts. Most big telescopes come with counterweights to provide balance (especially when the telescope is tilted and the weight is shifted to one side). Because of gravity your telescope will be pulled down, and nothing is more frustrating than pointing at an object, locking the telescope, and then having the telescope move down and loose the object in view because of gravity. And remember, this is a magnified view so even the slightest movement can cause your telescope field of view to shift a lot.

The first two points have to do with the product, the next point has to do with what do you want to view and where do you plan to use it? Just as different kinds of camera lenses provide different views so do telescopes. If you want to view the planets and the Moon at high magnification you would want those with big f-numbers (ratio between the focal length and the aperture) and large aperture (the bigger the diameter the more details resolved). If you want to view deep-sky objects those with small f-numbers are ideal as they focus the light in a smaller image. Large apertures are still a good option since the bigger aperture also collects more light. However viewing deep-sky targets require you observe in dark skies (the darker the better) away from urban cities since light pollution hides these objects. Some astronomers would recommend a 4- or 5-inch reflector as a good starting point because it has a good enough resolution and light gathering power. It also isn't bulky enough that it becomes hard to travel with to those dark skies.

If you're looking for a good enough telescope for your child to begin with a good place to start are those table-top telescopes. Our friends at Cutting Edge, the local distributor of Celestron telescopes, have some models of the FirstScope series which is relatively cheap, light weight and very easy to use. And when they grow up, a little tinkering can allow you to add a tripod to it. Other entry level (locally available Celestron models) we can recommend that are of relatively good quality and easy to use are the Cometron 114AZ, TravelScope 70, AstroMaster 70AZ. For much older beginners you can look at the higher PowerSeeker series (80EQ, 114EQ, and 127EQ), or the C90 (requires a sturdy video tripod).

'Tary' MSA's Celestron FirstScope

If you're going to purchase a telescope it is always good to look at reviews. Look at the pros and cons of the model, and be skeptical of reviews with no cons. The experience of others can help save you from making a bad investment. For those buying online, check the rating of the seller as well.

And of course we could not stress this enough, if you have the opportunity go to our free telescope viewing events and look through the different telescopes setup – this will allow you to get a feel of what to expect and of course interact with the volunteers to ask more about the equipment. This coming February 16, 2019 is the 3rd Philippine Telescope Hour where we encourage members of the astronomical community to setup their telescopes for at least one hour to share the view of the night sky to their respective areas. This is a good opportunity to see what telescopes are being used and to share your love for astronomy if you have a telescope with you.


Learn more about telescope specifications through GAIA-ORACLE's Comparative Optics.
Or see other telescope offers/reviews at the Philippine Astronomy Exchange.