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New telescope questions

by Sheneron
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Waveform
#19
Jan5-09, 02:14 PM
P: 69
Yes, this really tends to be a problem when moving a scope between temps, humidity, and dew points.

Personally I also cap the optics if I have move the scopes. However, I primarily leave the scope out.
I have it well covered and protected.

This is why a lot of people will build small observatories (shed's, small out building and such with sliding roofs). It minimizes moving the telescopes and also the wide swings in temperature.

Even the 80mm refractor, I try to leave it out, much as possible.

However, if circumstances warrant the scope must be brought in, then I agree with russ_watters unless you want to start playing around with 12volt Dew Heaters.
mgb_phys
#20
Jan5-09, 02:28 PM
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P: 8,953
Another technique is to put the scope inside a garbage bag and close the end while outside. The scope is then packed in dry air before you bring it indoors.
russ_watters
#21
Jan5-09, 03:59 PM
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P: 22,297
Quote Quote by Waveform View Post
However, if circumstances warrant the scope must be brought in, then I agree with russ_watters unless you want to start playing around with 12volt Dew Heaters.
Well - depending on where you live and what equipment you use, they may be a requirement. They are for me.
Sheneron
#22
Jan5-09, 05:22 PM
P: 360
Thanks for the advice, and thanks for telling me about covering the scope to prevent dew; I didn't know that should be done.
Sheneron
#23
Jan8-09, 05:46 PM
P: 360
Hi again
I am trying to collimate my telescope for tonight, but I am having some problems. I am stuck on the first step... I am using a cheshire eyepiece which I just bought.

The first step reads: Insert eh Collimation eyepiece into the focuser far enough that the bottom edge of the barrel appears slightly larger than the outer edge of the secondary mirror when looking through the site hole.

The problem that I am having is that I can not even see the edge of my secondary mirror. The secondary mirror fills up the entire barrel, and then just a little bit more. What should I do? Is that normal?
Sheneron
#24
Jan8-09, 05:56 PM
P: 360
Wait, nevermind
Sheneron
#25
Jan8-09, 06:48 PM
P: 360
Ok, new problem. I can see the edge of the secondary mirror as well as the secondary mirror holder. However, I can't see the bottom edge. What I need to do is adjust that upwards from the perspective of looking through the focuser. I know that turning the screw in the center adjusts is left and right, but how do I adjust it up and down?
russ_watters
#26
Jan8-09, 06:53 PM
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What is the model of the telescope?
Sheneron
#27
Jan8-09, 07:14 PM
P: 360
This is my scope:
http://www.telescopes.com/telescopes...rtelescope.cfm

I should add, the manual that came with the scope is grossly incomplete and did not even mention adjusting the secondary mirror at all.

Oh and I should add again, The secondary mirror is held by 4 support beams. It looks the same as the scope in this video: http://www.andysshotglass.com/Collimating.html
Sheneron
#28
Jan8-09, 08:47 PM
P: 360
I found this website: http://www.adur-astronomical.com/col...on%20guide.htm

and my scope has screws the same as that for adjust the spider vanes. However, mine are so tight that I can not turn any of them. Does anyone have experience with this? I'd like some advice before I really try to twist them.
Sheneron
#29
Jan8-09, 10:12 PM
P: 360
Yes, the secondary mirror is not centered with the primary when looking down the OTA. I need to figure out how to adjust the spider vanes so that I can center it. I was hoping to go out tonight, so if anyone know anything you know where to find me. Thanks.
Sheneron
#30
Jan9-09, 03:30 PM
P: 360
I called the company to make sure I could turn those screws, and yes I can. So I think I am getting it! Can't wait to go out tonight with a perfectly collimated scope. I will also try the star collimation.
Redbelly98
#31
Jan9-09, 04:01 PM
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Great! FYI, it may be easier to do the collimation and finder-scope alignment in daytime.

Good luck.

Mark
Sheneron
#32
Jan9-09, 08:07 PM
P: 360
Nevermind, I am still having a problem. No matter what I do I can't get the secondary mirror centered. When looking through the sight-tube, the secondary mirror is centered in the x-axis, but it is not centered in the y-axis. I can see the top of the secondary with some room, but I can't even see the bottom at all.
montoyas7940
#33
Jan9-09, 10:06 PM
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P: 274
Is the secondary too close to the primary?
Sheneron
#34
Jan9-09, 10:20 PM
P: 360
No I am talking about the other direction. I have it centered in that direction. When I look through the focuser I can only see the top and not the bottom no matter how I adjust the spider vanes. Does anyone know how to fix this?
Sheneron
#35
Jan9-09, 10:52 PM
P: 360
How exactly centered does the secondary mirror need to be? Does it make a large difference?
Sheneron
#36
Jan10-09, 12:01 AM
P: 360
....now my screw aren't even tilting the mirror. I can't figure out at all how to get this collimated. I have been trying basically all night. So frustrating.... another night lost.


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