Wanted
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Wanted
Hi has anyone got a telescope or powerful binoculars with a tripod suitable for a bit of amateur star gazing.
Thanks
Thanks
ssteventon- Posts : 37
Join date : 2013-06-18
Age : 66
Location : LA ALQUERIA
Re: Wanted
Check out thr binos they hsve in lidl. They are made by bresser which are supossed to be good quality.
Re: Wanted
I concur Dave, got a pair myself from Lidl and very pleased indeed at the price. I just lay on a sun bed and look at the stars through the binoculars - amazing, especially if you can get somewhere without light pollution.
Re: Wanted
Word of advice: Dont buy 2nd hand optics, without having them cleaned, serviced and checked for alignment.
Re: Wanted
Thanks Dave for the advice
ssteventon- Posts : 37
Join date : 2013-06-18
Age : 66
Location : LA ALQUERIA
Re: Wanted
2nd hand optics???!!...I like to pour freehand!
bantams56- Posts : 167
Join date : 2012-01-13
Location : Near Galera
Re: Wanted
The simple way to check a telescope is a "star test".
All these tests have to be carried out while looking at a star and pretty easy to do.
If you are checking out a refractor, point it at a bright star, then adjust the focus so that the star is out of focus. It should appear as a series of circles. Then go to out of focus in the other direction. The star should go back to a pinpoint and then re-appear as the same sort of circles. If it doesn't appear the same on either side of focus, or you can't get it to a pinpoint, the telescope is duff. (But you need to make some allowance for atmospheric turbulence).
If you are looking at a reflector, AKA a Newtonian, it's a little more complicated. Do the same test as above, but it's unlikely that you'll get perfect circles, as reflectors need collimating - i.e. to have their 2 mirrors perfectly aligned. So the out-of-focus star won't appear as a circle and you'll need a tool and some screwdrivers to align all the gubbins properly.
Whichever type you go to see, arrange to check it under a starry sky. Just looking through it in daylight won't reveal any faults (unless it actually has bits hanging off )
All these tests have to be carried out while looking at a star and pretty easy to do.
If you are checking out a refractor, point it at a bright star, then adjust the focus so that the star is out of focus. It should appear as a series of circles. Then go to out of focus in the other direction. The star should go back to a pinpoint and then re-appear as the same sort of circles. If it doesn't appear the same on either side of focus, or you can't get it to a pinpoint, the telescope is duff. (But you need to make some allowance for atmospheric turbulence).
If you are looking at a reflector, AKA a Newtonian, it's a little more complicated. Do the same test as above, but it's unlikely that you'll get perfect circles, as reflectors need collimating - i.e. to have their 2 mirrors perfectly aligned. So the out-of-focus star won't appear as a circle and you'll need a tool and some screwdrivers to align all the gubbins properly.
Whichever type you go to see, arrange to check it under a starry sky. Just looking through it in daylight won't reveal any faults (unless it actually has bits hanging off )
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