New Telescope

[AndyBill]

hi ,

ive just received a new telescope and put it together(correctly i hope!)

the manual gives no info on lenses , i have a 3x Barlow lens, an Erecting Lens,

and 3 lens marked K9, K12 & K20.

are these lens used singly or do they mix & match?

there is a viewfinder on the end of the tube, is this for a rough aim at the stars?

there isnt too many stars around tonight but i aimed at a distant bunch of three

and put the K20 lens in and managed to see them in the eyepiece but it didnt really magnify them

much, in fact they looked the same size as if i was looking just through my eyes!

i was hoping on something big to practise on like the moon but its nowhere to be seen!

does the telescope need to be calibrated at all?

the manual mentions balancing the telescope in Right Ascension and in Declination.

but does this need to be done first to be able to see stars properly?

sorry for all the (probably dumb) questions .

any advice would be graet

thanks

AndyBill

[Whippy]

What telescope have you got AndyBill?

Tony..

[AndyBill]

hi,

it is a Traveler SU 7535, they have a website on www.traveler-service.com/uk

[Whippy]

Hi AndyBill

From the link, it would appear that you have a 76mm aperture reflector. What you'll need to do first is set the scope up and make sure it's all in balance. Have a look at this: http://www.themcdonalds.net/richard/astro/writings/setupEquatorial.shtml .

Then once you have done that, the 'viewfinder' is called a finderscope. It's a little telescope with a wide field of view that will help you locate the object(s) you are looking for. (This is best done during the day, but can be done at night although it's a little trickier) All you need to do here is put one of your eyepieces into the focuser on the telescope and point it at something like a church steeple, TV arial or a bright star, and align the view in the eyepiece with the view in the finderscope by turning the adjustment screws that hold the finderscope in. The idea is that you use the finderscope to look for a particular object in the night sky and once you've found it, you'll be able to use your telescope to view the object properly.

HTH

Tony..

[AndyBill]

thanks for that ,

thats very helpful,

what lenses should i be using? as i said i have a K9, K12 and K20,

also a 3x Barlow lens and an Erecting Lens

ANdyBill

[dogfish]

Hi AndyBill

Welcome to SGL. Your eyepieces give different levels of magnification but with higher levels of magnification giving smaller fileds of view (i.e you can see less of the part of the sky you are pointed at). Rather peversely, or so it seems, the ones with the largest number (K20 in your case) gives the least magnification but the widest field of view, whereas the one with the smallest number (K9) gives the highest magnification but a narrow view of the sky. It is usually easiest to start with a wide filed of view and once you have located the object, centre it in the middle of your view and then increase the magnification by putting in a higher power (lower number) eyepiece to give more magnification.

You also need some targets to look at. A couple of good ones at the moment are Mars and Comet Holmes. Both are in the same general region of the sky at the moment (south east-ish). You can find Mars most easily by using a program like Stellarium (http://www.stellarium.org/) which is a free planetarium package which shows you the sky from your position (after you've entered your location, either as coordinates or by looking in the city database). You can also see it as the 'red star' in the southeast, although it won't be very high up until later on tonight. It won't be very impressive in your scope, indeed it's not very impressive in many scopes as it's quite a small object. But hy, at least you can say that you've seen it. Comet Holmes can be found by locating the star Mirfak, in the constellation of Perseus. Once you find this star, using Stellarium again, you'll find comet Holmes just to the East and down a bit from Mirfak. This will be quite a nice sight in your scope. It will look like a fuzzy ball.

Let me know how you get on.

Cheers, Martin

[Albireo380]

Good advice Martin. Comet Holmes should look just like a fuzzy snowball in AndyBills 'scope.

Another good objetc to look at is Mizar & Algol in "the Plough" - a nice crisp double star (Algol is itself a double).

Tom

[AndyBill]

Thanks Martin,

great program that,

can you tell me what the Barlow lens is for?

cheers

Andy

thanks too Albireo380

[Albireo380]

The barlow will double or triple (depending on the barlow) the magnification for any given eyepiece. But remember, it will narrow the field of view and dim the view you get.

Tom

[AndyBill]

Thanks Tom , right im off to find me a star

thanks all

[Tiny]

The Pleiades are a nice starter object too. They are a star cluster which is big enough to be visible to the eye (and so easy to find in your finder). With the eye you will see about 8 stars, though the finder more than 8, through the telescope with the 20mm in a lot more than 8. Once you find them you will find you have to keep adjusting the controls to keep them in the eyepiece. (Because the earth moves - not the stars.)

Of course before you look at anything it's best to get your eyepiece in focus on any bright star and once it is in focus to leave it alone while you find the next object then refocus if necessary, or change eyepieces and refocus. All the time you are doing the changing/refocusing, the object will be moving across your view field, so, if you do decide to change from one eyepiece to another centre the object and make sure you know which knobs to turn on your mount to get it back in the centre when it drifts off or even out of view.

Of course you will want to try all the eyepieces, see what is what and lots more BUT working in the dark with strange stuff it might be better to start with just the 20mm eyepiece. A starter run plan might be to - get the telescope lined up roughly on the pole star then use the finder to get you there and then focus the eyepiece on (say) the star Alderbaran - which is roughly east heading south, is red and is a good starter for going to next object - the Pleiades. With this large eyepiece filling cluster you can too practise moving the scope with the controls. After that (still using the 20mm) try for the comet and near that are some lovely star clusters also in Perseus. Some double stars next - the ones mentioned already - Alcor and Mizar and if you can find the head of Cygnus the swan that is a beautiful two coloured double star. On the double stars you can try out l your eyepieces.

If you get that far you are on your own - Orion has tons of stuff, mars is rising but don't expect too much. In the early morning Saturn will be up. (Iit will rise earlier each night so by the spring it will be in the evening sky.) Saturn is the wow object - it's the one with rings and more rings but with your scope maybe just ring. And then there's the moon.

Some people only look at the moon as there is so much to see. It's a few days old now with a bit more than a cresent showing but each night there is more moon though the bit that really shows detail is where the dark meets the light as the sun rises. Though a scope you can watch the sun illuminate mountain peaks, run down into valleys and as it does outline details on the surface. Its fascinating to watch so - enjoy.

[dogfish]

Thanks Martin,

You're welcome.

can you tell me what the Barlow lens is for?

Tom has answered that for you.

Tiny has given you some good advice too. The Pleiades should look lovely in your scope and stick with the 20mm for now, although if you can find Mars you could try higher magnifications. You mentioned not seeing the moon. This is because its rise and set times vary. This site http://www.croydonastro.org.uk/Twilight.htm provides pdf tables so you can work out when it's visible.

Enjoy your scope and feel free to ask more questions.

Cheers, Martin