Author Topic: Cheap Guide Scope?  (Read 5187 times)

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mickw

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Re: Cheap Guide Scope?
« Reply #15 on: Dec 19, 2007, 13:31:48 »
How many have actually invested in this precision instrument and would like to make some use out of the mount ?

I have just made a bush to centre the bolt for the mount onto the tripod - would anybody else like one while I am in the mood ?

I'm sure the bearing/shim can be improved with a piece of a cornflakes box.

Oh dear........................

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Mike

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Re: Cheap Guide Scope?
« Reply #16 on: Dec 19, 2007, 13:39:38 »
I think people were buying it jsut for the scope to use as guide scopes. Can someone bring one along to the meeting please? I'd like to see if the optics are any good for a Guide Scope.
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Ian

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Re: Cheap Guide Scope?
« Reply #17 on: Dec 19, 2007, 14:08:40 »
I did actually get mine out as there was a brief break in the clouds last night. Using just what came out of the box I was more impressed than I expected to be...

The mount. Well what do you expect. It holds the scope up. Don't touch the OTA if you can help it, the mount isn't particularly rigid, but remarkably it damps down in under a second I estimate.

The finder. Oh dear. Throw it back in the box. But not all is lost, the finder bracket has a hole, which pretty much lines up with the edge of dew shield. There you go, zero power finder.

The eyepieces. Thought the tubes were empty these are so insubstantial. However, they do actually do what it says on the box, and if you're a particular sort of masochist, you can use the 4mm. On cold nights, try not to freeze cornea to eyepiece, it smarts. Eye relief was never the Kelner designs strongest point.

The diagonal. Yes it is. Seems to work, but it's the only one I own (pleasures of being a newt driver normally) so I have nothing to compare it to. It's probably just a bit of mirrored plastic...

The OTA. Now then, the crux. It's Meade blue. It has a 1.25" focusser with the expected molasses style grease on the rack. It seems to track parallel to the axis of the scope. The end is plastic with a couple of setscrews to hold eyepieces and so on, I can see this being an early failure so some sort of replacement would be good to design.
It has a built in dew shield. Not retractable but substantial and it'd protect the objective from some abuse. There don't appear to be any internal field stops in the scope, so it really is 70mm clear aperture. There seem to be a couple of internal baffles to reduce stray reflections.

I had a look at two objects last night, between the clouds. Firstly I looked at the moon. It was low in the sky so swimming about in the eyepiece like astronomers at a December DSC. But, it appeared pretty clear of colour fringes with the 20mm with some crisp views of the terminator. I tried the 4mm and it wasn't bad, but without tracking and a mount the wobbles when you touch it, it was more trouble than it was worth. Just because, I tried my binoview, but there was insufficient in travel for it to focus without the barlow lens, and 10mm eyepieces in the binos didn't make for good viewing. Not to mention that the binos took the scope way beyond the mount capablility. I'll give it another go when the scopes on my Vixen GP.

Finally I took a look at Mars. It was a bright spot with the 20mm, but the 4mm showed a disc. It showed some colour, although this could easily be from the eyepiece as from the objective. I'll put a plossl on it next time to find out. There was a hint of detail in the disc but the scope doesn't have the focal length to show any more.

I'll image with it when I get it on the vixen, that'll answer lots of questions but I think for a guide scope, it'll do as well as any other f10 70mm scope. For 50 notes, why not?

Mick, I don't think I'll be using the mount, so I'll decline your offer of a bush, but thank you. I may try and get a cornflake packet to help. I think I'll put the finder scope in it.

mickw

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Re: Cheap Guide Scope?
« Reply #18 on: Dec 19, 2007, 14:16:49 »
Will bring mine tomorrow.

I agree about the use, but i was thinking it would make a handy lightweight mount just to sling in the back of the car.
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Rocket Pooch

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Re: Cheap Guide Scope?
« Reply #19 on: Dec 19, 2007, 16:00:44 »
mickw, I'll be back in the uk at the weekend, can you pm me your address and telephone no and I'll arrange to pick it up.


mickw

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Re: Cheap Guide Scope?
« Reply #20 on: Dec 19, 2007, 16:14:54 »
Chris, I live in Dulwich, would it be better for you if I take it to the meeting tomorrow for someone to babysit and you can pick up locally ?

Mick
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Ian

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Re: Cheap Guide Scope?
« Reply #21 on: Dec 19, 2007, 16:17:25 »
Tony G is probably best, but I can take it. I am but a short hop down the A20...

Tony G

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Re: Cheap Guide Scope?
« Reply #22 on: Dec 19, 2007, 20:18:06 »
Hi Mick,

I'll pick it up off you tomorrow if that alright, and pass it onto Chris the weekend. (after I tell the wife that I got her the present she had always wanted, knowing that she'll throw it back at me, that way I can say that at least I got her something, and then pass it onto Chris. Job Done. :lol:)
"I'm normally not a praying man, but if you're up there, please save me Superman." - Homer Simpson

mickw

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Re: Cheap Guide Scope?
« Reply #23 on: Dec 19, 2007, 20:42:19 »
OK, thanks for that I'll bring it tomorrow.

I dare say Chris will discuss the fee for its use as a pseudo present  ;)

Cheers,
Mick
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Rocket Pooch

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Re: Cheap Guide Scope?
« Reply #24 on: Dec 19, 2007, 22:35:59 »
Easy £49 and a free lightbridge