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Old 22-March-2003, 07:02 AM
draco draco is offline
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March 15th was my son's birthday and we got him a Jupiter by Meade 60mm telescope. The first night we picked out Jupiter and could make out atleast 4 moons. The following clear nights we managed to catch Saturn with its rings in full view. The problem I have been having is keeping up with the rotation as I keep Saturn aligned. As of now rain is in our forcast for the next week. I couldn't get Saturn centered using the 4mm eyepiece and would like to hear any tips or tricks on doing just that.
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Old 22-March-2003, 12:40 PM
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Kaptain K Kaptain K is offline
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A 4mm eyepiece is useless with your telescope.* The magnification is found by dividing the focal length of the scope by the focal length of the eyepiece. The focal length of your scope is 700mm. 700/4 = 175X. Unfortunately, the laws of optics do not allow unlimited magnification. If you go over 50-60 X/inch, you are simply magnifying inherent abberations of the optics. 60mm = 2.4". 2.4 x 50(60) = 120(144)X. Back off to a longer FL eyepiece.

* Meade should know better.
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Old 22-March-2003, 04:31 PM
AstroCreep AstroCreep is offline
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I have the same problem with my 700mm bushnell telescope. Unfortunately, I only have a 20mm and a 4mm lense. so I use the 20mm lense, and get a great view of the moon, and can see jupiter and saturn as disks, but I cannot make out the rings of saturn (disapointing) I also have a cheap Barlow lense that came with the scope, but I have no idea how to use it. I lost the instructions. anyone have any tips?? and what eyepiece should we use with our 700mm scopes?
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Old 22-March-2003, 05:38 PM
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The Bad Astronomer The Bad Astronomer is offline
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I have links for new telescope users on my website.
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Old 22-March-2003, 09:48 PM
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To use the barlow, stick it in the telescope in place of the eyepiece and stick the eyepiece in the barlow. A 2X barlow will make your 20mm eyepiece perform like a 10mm eyepiece (although usually with better eye relief). 20mm eyepiece + 3X barlow = 7mm.
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Old 27-March-2003, 04:15 AM
draco draco is offline
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I have a 25mm and 12.5mm and what you are telling me is to use the 12.5 to get 700/12.5=56 power. Which is what I was using that night. When I put the 4mm in I couldn't see a thing. Oh well I still think I got a sweet deal on the scope. It was purchased new $49.95 with Starry Night Software Bundle. Vinny is 9 years old and thinks it's the greatest thing.

I was looking at the possibility of hooking a digital camera to it in the future. I saw a few that costs less than $100 on the net are they worth it?
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Old 27-March-2003, 07:04 AM
russ_watters russ_watters is offline
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I have a 900x60 and I use a 4mm eyepiece just fine. Its more magnification that the scope can really resolve, but it doesn't look too bad.

Draco, it just sounds to me like you are having trouble aiming and tracking it? Its an alt/azmuth type mount, isn't it? I had one and I returned it to get an equatorial. Alt/azmuth is useless for anything but terrestrial.
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Old 27-March-2003, 07:56 AM
draco draco is offline
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I found a 10mm eyepiece and caught Jupiter tonight. I could make out the banding very clear plus 4 to 5 of the moons that's about 10%! I plan to take the scope out camping this week (spring break) with the kids. We live in the city and the lights really mess things up trying to zero in on objects. Saturn moves so fast, I have to predict where it's coming from and tell the boys, "Hey look quick!" in about 5-10 seconds it's gone.

The scope is "Jupiter by Meade" and the tripod is well built. My son asked if we could see pluto, I told him you can but it will just look like a faint dot.
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Old 27-March-2003, 01:21 PM
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I think it will be nearly impossible to do any astrophotography with an alt/az type mount, won't it? I went for an equatorial mount primarly because I wanted my husband, a photography buff, to get some fun out of the scope too. Have fun camping--great sky views at Wilderness State Park near Mackinaw City--it was really dark last time I was there.
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Old 27-March-2003, 05:30 PM
aurorae aurorae is offline
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Default telescope mounts

Quote:
Originally Posted by russ_watters
Alt/azmuth is useless for anything but terrestrial.
That is not exactly true. Alt-Az mounts, if they move smoothly, are very nice for visual observing, especially rich field.

They are great for "grab-and-go" observing, too.
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Old 27-March-2003, 08:16 PM
Hale_Bopp Hale_Bopp is offline
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Yes...even major research telescopes can be alt/az mounts. See the Sloan Digitial Sky Survey 2.5 meter telescope, the ARC 3.5 meter telescope, and I beleive even the Keck telescopes are alt/az.

If you want to use them for photography, you just need a field derotator. Difficult for amateurs, but not that bad for big professional instruments. And I know some amateurs use field derotators also, although using an equitrial mount is more common.

Rob
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Old 29-March-2003, 04:20 AM
tracer tracer is offline
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Quote:
Originally Posted by draco
I found a 10mm eyepiece and caught Jupiter tonight. I could make out the banding very clear plus 4 to 5 of the moons that's about 10%!
5 moons? You could actually see Amalthea?! *jealous*
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