Welcome to my little portion of Meade4M.org. I am thrilled that Meade established this community. In some ways it is a logical expansion of what I have been promoting since I created "Weasner's Mighty ETX Site" (http://www.weasner.com/etx) in September 1996 (egads, almost 10 years ago!). Communication and sharing is what the Web is all about. That is how I approached my web site from the beginning. I am honored that Meade invited me to participate. I hope that you will find these articles valuable.

I will be doing a series of articles describing just what you can do with the new small telescope you have purchased. Even if you have not purchased a telescope yet, you may be considering one and wonder just how it will perform. Certainly what I will be discussing will be applicable to the Meade ETX telescopes but the information can apply to any other small telescope. By "small telescope" I mean any telescope with an aperture of up to 5 inches (127mm). I will try to keep these articles as non-technical as possible so that even new telescope owners will be able to use the information provided.

There will be four articles on using small telescopes:

Part 1: Visual Astronomy for Fun
Part 2: Visual Astronomy for More Serious Pursuits
Part 3: Simple Astrophotography
Part 4: Advanced Astrophotography

Lets get started.

Part 1: Visual Astronomy for Fun

There are many fascinating objects in the sky that can be seen really well through your new small telescope. You should not expect to see the same details and colors in them that you see in photographs in books and magazines or even on the box the telescope was in. You bought a telescope to look through and that is what I encourage you to do. So stop looking at the books, magazines, and the telescope box and get outside! BUT WAIT!!!! First, read the telescope manual three times, play with the telescope indoors to learn how to operate it, and read this article. Then you may go outside.

OK, so now you want to know why you will not see those same colors and details that appear on the telescope box.

Basically your eye is to blame. The human eye was not designed to see lots of colors and details in the dark. You can observe this when looking around the audience in a darkened movie theater. You can not easily make out the color of clothes and the faces on people around you. On the other hand, when standing in line outside the theater you can see lots of colors and details in your surroundings. A camera can capture color and details easily in the daytime and at night with longer exposures or some "trickery". While the daytime photos may closely match what your eyes see, your eyes can not increase the exposure or do that same "trickery" when looking through the telescope at night. (We will discuss that "trickery" in Part 3 and Part 4.) But for many objects, you can see hints of color and some details. What you will see will depend upon the telescope, the "seeing" conditions, how you look at the object, and the object itself.

The telescope

The more light that reaches your eye the more effective your eye will be at seeing objects through the telescope. The amount of light that enters a telescope depends upon the diameter (called "aperture") of the main skyward lens or opening. Typically the larger the telescope, the more "light gathering power" the telescope will have. But once the light enters the telescope it begins to be affected by the lenses and/or mirrors in the telescope so that what comes out of the telescope and into your eye is less than what went in. When light hits a lens most of the light goes through it but some is reflected off the lens surface and some is absorbed by the lens itself. If there is a lens on the skyward end of the telescope you have already lost some light. Many telescopes also have one or more mirrors. Almost all the light hitting a mirror is reflected but not all, so some more light is lost. Then you add the small lenses in the eyepiece; light is reflected from their surfaces and absorbed, so more light is lost. After all this, the remaining light finally comes out of the telescope into your eye. It is not as bad as it sounds. Early telescopes suffered from light loss but today's telescopes have very efficient "coatings" and materials that allow a large percentage of the light entering the telescope to reach your eye.

The telescope focal length, when combined with the size of the aperture, also influences what you see. It affects the magnification of an object, but it also affects what is known as the "speed" of the telescope. In the days before digital cameras, dealing with shutter speed and "f-ratios" (typically shown as "f/") was common. We said an "f/2.8 lens" was "faster" than an "f/5.6 lens". That meant that more light reached the film with the f/2.8 lens. The same applies to telescopes. An f/10 telescope is faster than an f/13 telescope. You can calculate the f-ratio by dividing the telescope focal length (say 1250mm) by its aperture (say 90mm); in this case the f-ratio is 13.9.

Magnification is the telescope's focal length divided by the eyepiece's focal length. With a 1250mm focal length telescope and a 26mm focal length eyepiece you have 1250mm/26mm which equals 48X. That means an object seen through the telescope with this eyepiece would appear 48 times larger (closer) than it would appear to just your eye alone. The theoretical "usable" magnification is typically twice the telescope aperture in millimeters (90mm = 180x) or 50-60X per inch of aperture (3.5" = 170-210X). However, most times you will not be able to reach this limit except under excellent conditions and on bright objects (like the Moon and brighter planets). The more magnification you apply, the larger the area the same light is spread out over, making the object appear dimmer to your eye. The less magnification you use, the more concentrated the light is in a smaller area, making the object appear brighter.

The larger the aperture the more "resolving power" the telescope will have. This means finer details will be visible under ideal conditions. But for most consumers purchasing a telescope this is not a consideration; you are not buying the telescope strictly for resolving power. You get what you get and most times you never come close to ideal conditions when observing. (Once you get hooked on amateur astronomy you may find that resolving power becomes a consideration.)

While a larger aperture means more light will reach your eye, it also usually means more cost and/or a larger telescope to move around. Hence my recommendation to get the largest telescope you can afford AND that you will use. Many times a new telescope buyer will buy a large telescope, only to discover that it is too cumbersome to move and set up so it ends up in the closet or garage. Remember: the best telescope for you is the one you use. A smaller telescope can get more effective and enjoyable usage for many people.

"Seeing" conditions

The Earth's atmosphere has a major role in how objects will appear in the telescope. As Dr. Clay Sherrod of the Arkansas Sky Observatory describes in one of his many excellent articles on my ETX Site:

"transparency" relates to how DEEP you can see in space through the obstacle of the earth's air. The better the transparency, the fainter the object or star that you might be able to see.
"seeing" has absolutely NOTHING to do with transparency; it is a gauge of how PERFECT, or steady, the image remains while you view it.
1) If the night is perfectly transparent, it is a low power night, but not necessarily a high power night;
2) If the night is perfectly steady, it is a high power night, but not necessarily a low power night;
3) If the night is transparent AND steady at the same time, it is a PERFECT night, both for low- and high-power viewing;
4) If the night is cloudy, it's Miller time.

Light entering your telescope will be affected by turbulence in the atmosphere. Turbulence can be in the distant atmosphere above you or from heat rising from the neighbor's roof or the street in front of your house after a hot day. Light from an object low in the sky has to travel through more murk than an object high in the sky. Finally, the air INSIDE the telescope tube can disturb the light making its way to your eye. You can reduce the effect of atmospheric turbulence by viewing objects near the zenith (straight up, or nearly so) or at least not over sources of heat. You can virtually eliminate turbulence inside the telescope by letting the telescope "cool down" to the ambient temperature if your telescope has been stored inside in a warm location. This is called letting the telescope reach "thermal equilibrium". A rule of thumb: set up the telescope outside but wait 30 minutes per inch of aperture before starting to observe.

While we can not do much about the weather and its effect on the enjoyment of the night sky, there is one man-made source that has a tremendous impact on how well we see objects: "light pollution". And it is getting worse in most places on the Earth. Light pollution is the light shining into the night sky from improperly shielded and poorly designed lighting. Just a few decades ago you could easily see the Milky Way from most towns and cities in the United States; today that is significantly less true. If you look into the night sky with just your eyes, what you should see is a sky "full of stars". Unfortunately, that is not the case from most towns and cities. You can only see a handful of stars at best due to the sky brightness. That is the effect of light pollution. When you view objects in the telescope through this light pollution, the sky may be as bright as or brighter than the object you are trying to observe. So what you see may be a disappointment, if you can see it at all. There are some solutions that can enhance the view, but that is a topic for a potential future article. If you want to learn more about light pollution, visit the International Dark-Sky Association web site (http://www.darksky.org).

How you look at the object

Looking through a telescope is not difficult. But actually seeing all that the telescope is showing you is a little more challenging. If the image is swimming around in the eyepiece because there is a breeze blowing or there is some telescope vibration, you will need to make some adjustments in the position of the telescope or change how the tripod is set up. Trying to catch those moments of visual clarity while the object is moving is challenging, and you should not have to work that hard. Two simple solutions are available. Do not extend the tripod legs to their maximum height. In fact, the less extension you use the less vibration you will experience. You can also put the tripod on a soft surface like a small carpet or the grass in your yard instead of on a concrete deck. Next, be comfortable when looking through the eyepiece. If you are standing hunched over you will not be relaxed. Sit down if possible. That allows you to concentrate on looking rather than standing. Let your eyes get used to seeing in the dark. This is called "dark adaptation" and can take 20 minutes to over an hour, depending upon your age and health. Once your eyes are accustomed to seeing in the dark, avoid bright lights! If you need to use a flashlight use one with a red cover over its lens. If you plan to observe the Moon, especially when it is more than just a thin crescent, remember that it will also affect your dark adaptation. You might consider using a Moon Filter or wear sunglasses (yes, that really does help). Finally, to see those really faint objects in the night sky use "averted vision". This means do not look directly AT that faint object but let your eye wonder off to the side of it while still concentrating on the object. The longer you look "at" an object this way, the more you will see it. It can take some experience to get the hang of this but with practice you will be amazed at what you can actually by using averted vision.

The object

Now we finally come to the fun part of actually looking through the telescope at some objects! So, just what will you be able to see with that new small telescope? Actually, quite a bit.

Our Earth's Moon makes a great first target. Using the Moon will let you get used to using your telescope and seeing how it performs at different magnifications. When the Moon is not fully illuminated you will be able to see a lot of details along the "terminator", the line of shadows dividing the illuminated and non-illuminated sides of the visible face of the Moon. Craters, mountains, valleys, and more will all be visible to you. And do not forget about lunar eclipses. While you do not need a telescope to view an eclipse, it is still fun to watch through a low power eyepiece. Jupiter and Saturn are also great first targets. When viewing Jupiter through almost any small telescope you will see at least two cloud bands crossing the planet's disk and you will see its brightest moons (one to four, depending upon where they are in their orbits around Jupiter). With a five-inch telescope you may be able see a shadow of a moon on Jupiter's clouds. And then there is the "Great Red Spot", which is actually not too great nor red right now (and has not been for years). But you can see it as a small pale pink-ish oval inside one of the cloud bands. You will never forget your first view of Saturn through a telescope; I still remember mine from 1962 with my new (at the time) Edmund Scientific 3" reflector. You will see the Ring System, a line apparently dividing the Ring (Cassini Division), some faint cloud bands on the planet's disk, and perhaps its largest moon, Titan. If the conditions are right, you will see the planet's shadow on the Ring and the shadow of the Ring on the planet's disk. That really gives a three-dimensional look to Saturn. Cool! Over a period of a few years, the angle of the Ring will change as both the Earth and Saturn change their relative positions in their orbits around the Sun. The planet Venus will at various times of the year show phases just like our Moon. Sometimes it will be crescent-shaped, other times more of a full disk, and all phases in between. The other planets are more challenging in a small telescope; but Mercury, Mars, Uranus, and Neptune can be seen; and depending upon your telescope and the conditions, you may see a small disk (without details, except for Mars which can show some surface markings, clouds, and the polar caps). Comets, when they appear in the night sky, do not generally make good telescope objects to view. About all you will normally see is the "head" of the comet, and it will appear faint and fuzzy. But still they can be nice look at. Some asteroids are also visible in small telescopes, and it is exiting to see one (just do not expect to see a disk). The last object in the solar system that you can observe in the sky with a telescope is our Sun. However, viewing the Sun requires some very serious protections, both for the telescope and your eyes. With the proper filters from reliable solar filter manufacturers you can see sunspots, prominences, and, of course, the partial phases of a solar eclipse. You may have heard about projecting the Sun's image through a telescope onto a piece of white cardboard. NOT USE PROJECTION with telescopes that have plastics or glue holding everything together! Also, DO NOT USE filters that attach to an eyepiece for viewing the Sun; if the filter cracks due to heat buildup (which will occur) while you are looking at the Sun, you can and mostly likely will be blinded, permanently. The only reliable and safe solar filter for your telescope is one that covers the aperture end of the telescope. And always cover the finderscope when viewing the Sun to keep you or others from inadvertently looking through it.

Galaxies (what used to be called "Island Universes") and nebulae ("clouds" of gas and/or dust) are beautiful in astrophotographs. But through most telescopes they are "faint fuzzy blobs". Through small amateur telescopes all you will see is generally a small object with maybe some shape (round, oval, or line) and some faint grey or green "color". Globular clusters, which are tightly packed groupings of stars, can also be faint and fuzzy in small telescopes, but there are several examples where you will be able to see that it is a cluster of stars very close together. Larger and brighter objects will have a better chance of showing some hint of details. The thrill of viewing these faint fuzzy blobs is not seeing the details but that you see these Deep Sky Objects (DSOs) at all. These are objects that are thousands or millions of "lightyears" away, so you are seeing them as they were thousands or millions of years ago. The bonus is when you can make out the shapes and finer details with your eye.

Stars can be fun to look at. Many are very nice, even showing a distinct color. Some stars are actually double or multiple stars when viewed through a telescope. When the stars have different colors the contrast can be very beautiful. A point about star size. Many new amateur astronomers are disappointed when they look at stars through their new telescope. They try increasing the magnification (by using shorter focal length eyepieces) and still the stars only appear as "points of light". Some new users will turn the focus knob to "enlarge" the image of the star. Neither will work and turning the focus knob to make the star appear larger just puts the image out of focus. Stars are very, very, very far away and while they may in fact be very large physical objects, the distance makes them appear as "point sources" of light. No amount of magnification will enlarge a point source of light, at least not with any telescope YOU can afford.

Finally there may be one more use for your telescope. Many telescope models will perform well as a "spotting scope" for terrestrial use. You can look at birds and animals far away or even planes and ships and distant mountains. When I was growing up in Southern Indiana I used my Edmund Scientific 3" telescope to watch B-58 Hustler aircraft do aerial refueling at night. (Little did I realize that a decade later I would be doing aerial refueling in an A-7D jet fighter!) If your location is such that you could view these Earth-bound objects, feel free to add terrestrial use to your telescope enjoyment.

Have fun and enjoy what the Universe has to show you!

Next time:

Part 2: Visual Astronomy for More Serious Pursuits

Comments on this series of articles or suggestions for future ones are welcome. Please email them to me at ETXAstro@aol.com. And please use an appropriate subject on your email; do not make your message look like SPAM!