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A Reflector, 80mm extension tube and a 32mm EP

skir

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skir

skir

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it's a waste of time focusing on objects less than 250,000 miles away. you need to use the sky, not rooftops.

I appreciate what you are saying, but clear skies here have been hard to come by of late so I'm trying to do as much as I can with what I've got available to me. I may just be making some newb idiot mistake, but I've checked the collimation over on this so many times now I really don't think I am getting something wrong now.

Would an out of line focuser tube cause the inability to focus I'm getting?

Any help with this would be greatly appreciated.

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Moonshane

Moonshane

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no sweat at all - my comment might have seemed harsh - I didn't mean it to be - should have added a smiley.

I think we all worry that our kit is not working properly in times of poor seeing etc. or when you leave a moon filter on and wonder why the Orion Nebula looks rubbish.

just wait for clear skies (or partially clear) and get a focus on Jupiter or the moon/stars and you'll see it's all OK subject to a (probably) shorter extension.

I doubt the focuser issue will be a problem in due course.

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skir

skir

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No worries. I hope the focuser isn't an issue. But I was unable to focus on anything on the two nights I did get clear skies. First night with either an 8mm or 32mm EP with no extension, the second night I think I got stars in focus with an 8mm and an 80mm extension, but was still unable to focus with the 32mm on anything at all. Ideally I want to get a look at the moon as this should prove conclusively if there's an issue.

Theoretically though could an out of line focuser tube cause focussing problems?

should I get resistance, friction and noise from the focuser when turning it?

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skir

skir

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generally horrible noises in crayfords can be adjusted out.

your comments suggest a 50mm extension would be OK.

Ok, thanks, so would you say a 50mm extension would be a wiser choice than a 35mm?

I guess to adjust out the noise and friction the focuser would need to be disassembled?

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Moonshane

Moonshane

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all my OOUK scopes need a 50mm extension to focus. you are better having the focus point too far out than too far in. adding an extension is easy, achieving more in focus is not.

I'd suggest finding out what you need first before buying anything else.

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skir

skir

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all my OOUK scopes need a 50mm extension to focus. you are better having the focus point too far out than too far in. adding an extension is easy, achieving more in focus is not.

I'd suggest finding out what you need first before buying anything else.

I certainly would rather know what I need than to just chuck money at the problem, it is just difficult to know what needs to be done at this stage. I'm not sure what to try next tbh.

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Naemeth

Naemeth

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At least from my end, my 26mm does take a lot of focus room (needs the focuser almost all the way out the achieve focus), but it does focus in the end. It just seems weird that you can't achieve focus without an extension tube.

Sorry if this has been suggested already, but here's what I would do:

Without an extension tube in, move over to the Moon and put your focuser as "in" as possible, and slowly work outwards, if this still doesn't achieve focus, slowly pull the eyepiece out until it achieves focus, then with a pen / sticker mark where that is, then the distance of that to the end of the barrel plus the focus travel should give you the minimum size of extension tube you need.

I agree with Shane, don't bother focusing on objects that are nearer than the Moon.

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skir

skir

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Well moon rise is early morning at the moment, but I think I'm going to have to pick a night with some chance of seeing the moon and get out and try and sort this out.

Should there be any friction and noise at any point from the focuser? I'm trying to work out if any other damage has been done to the scope other than just the bent thumb screw.

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Moonshane

Moonshane

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I certainly would rather know what I need than to just chuck money at the problem, it is just difficult to know what needs to be done at this stage. I'm not sure what to try next tbh.

try what I suggested above but on the moon or more distant objects. that's the only way to establish where the focus point is. if you follow it step by step you'll find the focus point.

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skir

skir

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it's a bit of a travel but I'd gladly help - I am in Stockport - maybe try more local observers?

Thats a very kind offer and if I was at home I'd drive over and take you up on it. However I'm currently down south with family and will be a for a a few weeks yet, so I'll have to try and figure it out myself and with the invaluable help on here. I've been learning a massive amount of info from this site so far and all the help so far is much appreciated.

The sky looks to be 100% clouded over tonight, but tomorrow looks like early morning might be better so I may try then.

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Naemeth

Naemeth

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I just suggested the Moon as you don't necessarily need to do it at night (not always clear) and it's obvious you've got it in view, you don't always see stars anywhere you point your scope, well, not in a heavily LP area anyway.

If you've got a Solar Film filter, you could always focus on the Sun, you don't need 100% clear either, thin cloud doesn't usually get in the way.

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Naemeth

Naemeth

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Just a thought. With a clear sky should I be able to see the moon during the day at the moment?

Yes, easily. You can make it out in daytime through all phases I believe (apart from New +/- 1 day) if you know where and when to look. It'll just be easier nearer the Full Moon for what you need it for.

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skir

skir

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seriously. just point it at a clear patch of night sky. it does not matter where, there will be stars in the eyepiece.

I think tommorow night may be my first chance of some clear sky, looking at the forecast at the mo.

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