PLEASE HELP ME - Im completely confused and New to Astronomy

[MrGlen]

I will let you know Allan, only I have a little trouble with Business Post.

After the great help from FLO in choosing my scope, they sent it out to me for next day delivery (29th December).

I received box 1 of 2 on the 31st which contained the scope but no mount, great. I then logged into Business post to see where box 2 was and it was in Norwich? Box 1 had been sent to Birmingham then onto Northampton then to me, why is box 2 in Norwich I asked them? Anyway I could go on for a long time about this, but I still havent got box 2 and a guy named Scot at Northampton depot kindly tried to sort this out for me today. He rang me back and said that Norwich were saying that it had been forwarded onto Birmingham, he rang Birmingham they didnt have it. So im a bit gutted. The sky is clear the stars are out but Business post have lost my mount!!!!!!

James (FLO) if you are there could you try and sort this out for me on Monday if I still havent received it.

Thanks James

MrGlen

[MrGlen]

Ok, well i havent got my mount yet, but thats not going to stop me.

Last night a friend came over with a lot more telescope knowledge than me. So we decided to set up the 200P even without the mount.

A black & decker workmate was ideal, telescope resting on two bits of Polystarin that came with the packaging pointing towards the moon.

A 3 tonne car jack underneath front of workmate to achieve elevation.

I didn't expect it to work, but it was perfect. I saw my first images of the moon through the scope, and what a view it was.

I was surprised at the speed the moon moves.

We looked through the 10mm lens first and it was pretty close up, then to my surprise the 25mm wide angle was a better overall look but not as close. Still good though.

Can anyone suggest a different lens as i know nothing about them, to enable a much closer view?

Overall though, very happy with scope and just cant wait for the mount to turn up.

[barkis]

Hi. Glen. If you know the focal length of your scope in millimetres, dividing that figure by the focal length of any eyepiece will give you the magnification. For example if you scope focal length is 1000 millimetres, and you use a 10 millimetre eyepiece, the magnification would be 100 times.

A rule of thumb as to the highest magnification in the UK is roughly 40x per inch of aperture of the instrument. So, if your mirror is 8" diameter, then the maximum mag. should be x320.

If the seeing conditions are excellent, then you may try a higher magnification.

The best views are the ones that are clear and defined to your eye. Extreme magnification can distort the view of your subject.

Ron.

[MrGlen]

Thank you for that Ron.

My telescope has a 1200mm focal length, Skywatcher 200P.

Could you recommend a lens that I could purchase at all, I have a 10mm and a 25mm Wide angle?

Cheers

MrGlen

[barkis]

I am not sure you should be buying higher power eyepices. Remember your telescope is a Dobsonian, and has no drive system. If you observe the moon for example at 200 times power, you will have to keep nudging the scope westwards to keep the moon in the eyepiece.

Because the earth rotates, that movement is also magnified greatly when you use a high magnification. You get irritated by having to constantly move the scope. Using your 10 millimetre EP gives a 120x mag. If you put a 2x Barlow lens in, then the magnification would double to 220x.

The moon would move quite quickly through the field of view. The best thing to do then, is advance the scope westward, and let the moon drift across the field. That way you get a prolonged view for a time at least.

Ron.

[MrGlen]

Thank you Ron.

I will probably get a 2x Barlow lens at some point.

Until then i will start to look for some other planets with the lenses ive got.

Cheers

Glen

[dark knight]

A barlow lense is useful. they come in various magnifications from 1.5x to 4x, effectively turning what eyepieces you already have into different focal lengths (I think). Your 10mm eyepiece becomes a 5mm with a 2x barlow. Another good addition maybe one of the 8mm to 24mm zoom eyepieces, this would allow you to zoom out, makingre-centeringthe object easier. As already mentioned, the objects can quickly move out of the field of view at high magnifications.

[dark knight]

In fact an 8mm to 24mm zoom eyepiece and a 2x barlow would give theequivalent of many seperate eyepieces, covering 4mm to 24mm fully inclusive. At the 4mm end of the scale this would equate to 300x magnification which is bordering on the max for your OTA.

[Helen]

I'd advise caution with a zoom for use with an undriven scope as the field of view can be quite small, and so the object would move very quickly and you'd have to keep nudging to keep up. Not a good recipe for detailed observing!

Helen

[dark knight]

fov @ 24mm is 40degrees and @8mm is 60degrees. a super plossl @ 9mm gives FOV 57 degrees. so the zoom at 8mm gives better FOV than the 9mm plossl. can't work that one outI totally agree about high mags and manual mounts not being an ideal thing, I didn't realise it was a Dob manually guided :withstupid: , however I am merely saying the zoom and barlow for about £80 total, potentially replace manyseparateeyepieces which is good if your on a budget. of course for £200 you could get a Antares zoom with a FOV of 89 degrees at 5mm :shock: :shock: .