Since this is the first in a series, I'll take some time to give an explanation of what the equipment is:
As you can see, the light comes in through the front of the scope, is focused by the primary mirror at the back of the optical assembly, reflects off the secondary mirror and is sent to the eyepiece. As with most things, bigger is (often) better. The larger your aperture, the more light the scope will gather.
With my scope, the aperture is 130mm, or just under 5"...which is pretty decent for a high-end starter scope. The focal length is the total distance the light travels from the front end of the tube to the exit at the eyepiece, which in this case is 650mm. You then divide the focal length by the aperture to get the focal ratio which is an f/5 in this case.
The focal ratio determines the image magnification, field size (how much of the sky you can see at one time), and the brightness of an image; all depending on the eyepiece used. 'Fast' telescopes with ratios around f/4-f/5 give a wide field of view, but are not specifically designed for high-magnification planetary viewing. For that you want a 'slow' telescope with a f/11-f/15 ratio.
Since my scope was a 130 ST (the ST stand for 'Short Tube') I sacrificed a bit of power for portability. The standard Orion 130 has a 900mm focal length and a f/6.9 ratio. But since I will be lugging this thing around, I needed something manageable.
Lastly, the eyepieces determine the viewing field and magnification. Each eyepiece has its own focal length which you divide into the scope focal length to determine the magnification. My scope came with a set of 25mm and 10mm eyepieces. This gives a magnification of 26x and 65x respectively. While you might think that more magnification is always better, this is not always the case.
Since I don't have a mount that has automatic tracking, I have to manually move the telescope to keep whatever it is I am looking at (so far only the Moon and Saturn) centered in the eyepiece. With the 25mm eyepiece, the views of the moon are great, and you can make out the rings of Saturn. However, with the 10mm eyepiece, the views of the moon are fantastic, but Saturn whips across the field of view in under a minute (so it's hard to track)...but you can make out the gap between the rings and the planet itself, and I have managed to spot Saturn's moon Titan every time. It's really pretty fantastic.
Living in the city, I'm fairly limited in what I can see due to the light pollution. I can only imagine what I would be able to spot once I can get this thing out under some nice, dark skies. Saturn will soon be setting for the season, but I think Jupiter will be in a good spot in a few months. Right now, Jupiter and Mars are in the East right before sunrise, and there is no way I am dragging myself out of bed at 3am...I'll wait a few more months.
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