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Help Needed
hi
i have a boucsh and lomb professional series telescope[specs are :
Professional 200-200x4.5" (F/7.9)
1.25" optical format.
Astronomical reflector telescope.
4.5" (114mm) aluminized, overcoated primary mirror.
2x barlow ]
heres my problem.... i found jupiter n fixed the telescope to it.... i saw it....but there was no magnification..it was still a dot even in the telescope except 4 lil dots near which i think were the galilean moons..i have 2 eyepieces 25mm n 10mm....cant understands why. help needed
It sounds to me like you may have an optical alignment problem. Are you sure you were looking at Jupiter? Your finder may be way out of alignment. You should have seen the disc easily with this size telescope.One suggestion, if you use the barlow, it will really narrow your field of view. You have a longer focal length, so it would really narrow the field of view. Try looking at some distant object in the daytime. Perhaps the top of a utility pole, or tree top. Center it in the middle of your low power eyepiece field of view. Then check the finder, the same object should be at the center of the finder. If not, adjust your finder scope so it is centered on the same object.Chris StephanRobert Clyde ObservatorySebring, Florida USA
im sure it was jupiter.... anyway thnx i'll chek again n look on for some other celestial objects
Hi ChrisThis will work well just if the used terrestrial target is pretty far away (say at least a mile or better more). If its too close one will introduce a parallactic displacement that will require a fine adjustment on a star. For this Polaris is the best target as it doesn't move much.CSWolfgang
Hi!
The magnification you get in the end is the focal length of the telescope divided by the focal length of the eyepiece.
So let's check.
Your telescope has f = 7.9 x 114 mm = 900 mm . If you also use the Barlow Lens, you'll get 1800 mm .
When using the 25 mm eyepiece, this will give you x 72 magnification
When using the 10 mm eyepiece, this will give you x 180 magnification
180 fold magnification is more than enough to see Jupiter as a disk. Sooo.... unless you used the 25 mm without the Barlow (==> x 36 which indeed isn't that much) maybe what you saw just wasn't Jupiter ??
Note that the Galilean moons should all be aligned in (more or less) a straight line. Sometimes you'll see fewer than 4 of them of course (when a moon is transiting Jupiter or is eclipsed by it). You can use free software like Stellarium to check what the moons look like at the moment of observation.
This is a rather typical view (randomly picked from Google)
http://home.cogeco.ca/~hobbservatory/Jupiter_Moons.jpg
As you see, when you can spot the four largest moons, you should already see Jupiter as a disk.
Anyway, for a telescope of 114 mm aperture, it would make sense to have magnification of up to ca. 240 so you might consider using an eyepiece of 7.5 mm. Higher magnifications will not reveal more detail because the aperture limits the minimum detail of the imaging because of diffraction of light.
Don't give up, Jupiter is a spectacular sight even at x 100 magnification and now is a good time to observe it because it's relatively close. Your telescope should be perfectly capable of catching it. Use the lower magnification first to fine adjust the finder scope on some bright star or Jupiter itself, and then try to catch Jupiter with higher magnification. If your mount is not fitted with tracking motor drives, Jupiter will cross the field of view rather quickly at high magnification, so you want to have a well aligned finder scope and you want to north-align the mount rather precisely so you have to adjust only one axis of the mount to compensate for the motion of the Earth.
Hope this helps, Heinz