Help getting a Starter Scope

For people new to astronomy who want to ask those questions that they were afraid to ask. Receive helpful answers here.
mrthomasyip
Posts: 56
Joined: Thu May 22, 2014 9:10 am
Favourite scope: 12" london bridge

Re: Help getting a Starter Scope

Post by mrthomasyip »

Hi Jeannie, welcome to the hobby.....and also welcome to the family of dobs users........
The Belief of Thomasology.
mrthomasyip
Posts: 56
Joined: Thu May 22, 2014 9:10 am
Favourite scope: 12" london bridge

Re: Help getting a Starter Scope

Post by mrthomasyip »

Welcome to the family of dobsonian........
The Belief of Thomasology.
Jeannie
Posts: 7
Joined: Sat May 31, 2014 11:34 pm
Favourite scope: no scope yet

Re: Help getting a Starter Scope

Post by Jeannie »

In case u guys got curious wat happened...In the end the scope works okay. I got too lazy to figure the shroud part. Keke.
Its interesting tho, I just happy looking at moon and planets now. Brought my tele to chalet and its really interesting. I got total strangers asking me if they can look thru the scope. Hubby and family did not want to sleep. I think the scope need collimating soon, the disc seems off when a star is off focus.. The children were pulling parts of the scope. Its a good height for small kids if the scope is on the floor. I used a chair to sit down.
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antares2063
Posts: 687
Joined: Sat Jan 22, 2005 3:34 pm
Favourite scope: Newtonians
Location: Bedok North Street 2, Singapore

Re: Help getting a Starter Scope

Post by antares2063 »

The views of moon is always fascinating for people looking into a telescope for the very first time...scorpius and sagittarius are up early this time of the year , many star clusters and nebula are around them for viewing.

regards,
Junwei
I miss the place where stars shine bright, to gaze upwards in awe of the sight
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cloud_cover
Posts: 1170
Joined: Mon Jul 12, 2010 6:08 pm
Favourite scope: 94.5", f/24 Ritchey-Chretien Reflector
Location: Restaurant At the End of the Universe

Re: Help getting a Starter Scope

Post by cloud_cover »

Hi Jeannie,
I have the 130p as well. Its a very nice scope and very capable for the price. Although initial collimation is less easy to set up because of the cost saving considerations of the design, I find that once collimated it tends to stay in collimation, especially if you snug down the longer screws at the back, which act as retaining screws to keep collimation in place. The main difficulty comes with secondary to focuser collimation but since you bought new, the shop should have at least made sure that part is reasonably collimated.
I find that a shroud greatly increases the ability of the scope. This is because a lot of stray light hits the very exposed secondary from all around. To see this effect, simply look at anything, even other buildings, first in a dark room, then turn on the lights. You will immediately see that the whole image is very much greyer and far less detailed because of the contrast-robbing effect of stray light. A shroud on the other hand, can be as simple as a rolled up tube of black vanguard paper (the stiff kind) stuck to the inside of your upper assembly ring with a hole cut out for light to pass from the secondary to the focuser.
With regards to round out-of-focus stars, do check with an experienced fellow hobbyist before coming to conclusions about your collimation. In a newtonian design, stars will not be round unless very close to the center of the field. This is due to coma, an inherent optical defect in newtonian mirrors. Don't worry about this; if its not troubling you, its not an issue. I personally find it quite mild in the 130p. Another reason why the stars may not be round is because there is quite a bit of wiggle in the focuser, meaning your eyepiece may not always be in the same position on the optical light-path, hence your collimation will be thrown off.
However, do let me say that despite these issues (which are addressed in premium scopes costing thousands), the 130p gives very pleasant views and you're not giving up very much at all to any other 5" reflector, so if you're enjoying the views, then don't even bother with my previous paragraph but enjoy the night sky!:)
DON'T PANIC
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