Quote:
Originally Posted by Jemmo
David I was just reading more about that set I put up and realized I dont really need that many I might just get 2 or 3 to start with and yeah great idea I got the dob off this page so I will look for some eps too. Since I'm a total noob could someone tell me good brands to look out for and just say I'm going to buy 2 or 3. What sizes should I go for
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I suggest you start with the two eyepieces you have before buying ANY new ones.
You've probably got something like a 25 mm (low power), and a 10 mm (medium-high power), or something similar. They won't be great eyepieces, but they should complement the telescope reasonably well. (There's not a lot of point in buying $200 eyepieces to use with a $100 telescope.) The existing eyepieces should allow you to get reasonable views of the Moon, Jupiter, Saturn, etc. The low power eyepiece will probably be "easier" to use (more eye relief, bigger exit pupil, etc), so I suggest you use that one first. (You'll probably find that it's the eyepiece you use most of the time anyway.) The 10 mm may give a dim view under even good viewing conditions, and you will probably find that you need to place your eye "just so" (absolutely on-axis, and very close to the eyepiece) to get a good view.
If you're struggling to get a clear view of Jupiter at night, you might find it easier to experiment in daylight hours, targeting a distant feature, such as a building or tree on the horizon. It's generally a LOT easier to work out which way to adjust the focus and so on in daylight, when you can see what you're doing properly. (And you don't need to wait for a cloud-free night, or for the target to get high enough in the sky!) If you can't get a decent image in the daytime, there is something very wrong with your telescope and / or eyepieces, and it won't perform at night.
Once you get a good view with the low power eyepiece, try the high power on its own, then maybe a Barlow with the low power, and finally a Barlow with the high power. You will almost certainly need to refocus a bit each time you change the eyepiece set-up. Chances are that if seeing conditions are good, you will get an "OK" view with the high power eyepiece on its own, but it will look pretty ordinary if you try to use the Barlow and high power eyepiece together under any but the every best seeing conditions. Any combinations that won't yield a good image in the daytime are probably not going to be much use at night.
When you're ready to try Jupiter again at night, start with the low power eyepiece, and don't use any of the Barlows or erect-image accessories. Bring it to focus, and you should be able to clearly make out the disc of Jupiter. With a small telescope and low power eyepiece, it might initially look like a small yellowy-white disc with no obvious bands, but it should be well-defined, and you're making some progress. You should also be able to see several of the moons (up to 4) as points of light - they look like stars, except that they're in a row, and pretty obviously associated with Jupiter rather than being random background stars.
If the image is reasonably stable with the 25 mm, try the 10 mm - it will be quite a bit dimmer, but you should be able to see a bit more colouration and detail. If the image in the 25 mm is shimmering and wobbling all the time, it will just look worse as you increase the magnification, so you're probably better off giving up on the planets for that night, and try looking at some of the bigger targets that are best seen at low power / wide angle, like the Great Orion Nebula.
Hope this helps!
