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Olli

Need help with Alignment and Focusing

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Hi all.

after receiving my scope yesterday  I went outside for about half an hour with it and was quite impressed on how easy everything is to set up and use. However I have two questions that I would like answered.

When viewing at the moon using my 25mm eyepiece I could see a blue and orange haze around the left and right side of the moon. Was this because I didn’t have eyepeice focused probably or is there another reason? And also while focusing I had a lot of vibration is there a way to reduce it.

Today I tried to get my red dot focused aligned with my telescope and I think I’ve managed o do it correctly but was concerned that my target was to close. My target was the Ariel on the roof top as I didn’t have any clear targets that were far away I had to choose that. I managed to get it aligned probably but heard that the targets were supposed to me further away?

 

Man Thanks 

Edited by Dinoco
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It would help if you gave details of the equipment that you were using. However, the colours you refer to are chromatic aberation. More info would provoke a better response I'm sure.

Peter

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If your alignment is not perfect but roughly ok, then just adjust it when pointing at the moon. That should be far enough :happy11:.

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I don't see how you will be able to eliminate vibrations as you are interacting with it all time. Red dot finder alignment is best done on a bright star. Good luck.

Peter

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IIRC I think you ran a thread where it was noted that the mount may not have been up to the telescope you wanted to put on it.  However, you could try placing a weight on that tripod tray (large bag of sand/sugar/flour etc) or arranging to dangle a weight under the top centre point of the tripod.  You could also find some rubber matting to go under the legs which might help act as shock absorbers.

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8 minutes ago, JOC said:

IIRC I think you ran a thread where it was noted that the mount may not have been up to the telescope you wanted to put on it.  However, you could try placing a weight on that tripod tray (large bag of sand/sugar/flour etc) or arranging to dangle a weight under the top centre point of the tripod.  You could also find some rubber matting to go under the legs which might help act as shock absorbers.

Hi yeah I did, it’s fine when I stop touching it of course but it’s abit hard trying to get focus right when it’s shaking so much I’m going to try with not having the tripod fully extended and see if that helps a bit. Will give putting a weight on it a go as well.

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40 minutes ago, domstar said:

If your alignment is not perfect but roughly ok, then just adjust it when pointing at the moon. That should be far enough :happy11:.

Thanks, it’s roughly centered will try it tonight if it’s clear.

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I have mine set up on decking. When I was using my EQ2 mount I only had to move my body (keeping my feet still) and this created vibrations within the scope. Also wind is a big factor with such a light scope/mount. Since I switched to my sturdier mount I have less vibration. I also bought a 2m x 2m pop-up gazeebo from a well know superstore for £60. Takes me five minutes to erect and shelters the scope very well from the wind. Obviously I only use the walls and leave the roof off! :) 
Just and idea for you.. 

Pete.

Edited by Redscouse
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I have a vibration issue too whilst focusing. Pretty much accepted it as par of the course for a starter scope. 

Need to also appreciate that you're viewing stuff that is a long long way off and the slightest of movements will be seen in the scope.

From my photography experience, better tripod and mount will help.

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It you have a garden chair then with lowering the tripod legs that should help minimise vibration.

Your telescope being a reflector will not naturally show chromatic aberration so this is creeping in from the eyepiece. The provided eyepieces are great to get going with but keep your eyes open for second hand bargains on here for example. A 30mm and maybe a 12mm or so.

Enjoy your new telescope, remember the mount head I think can in time be moved to sturdier legs.

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7 minutes ago, happy-kat said:

It you have a garden chair then with lowering the tripod legs that should help minimise vibration.

Your telescope being a reflector will not naturally show chromatic aberration so this is creeping in from the eyepiece. The provided eyepieces are great to get going with but keep your eyes open for second hand bargains on here for example. A 30mm and maybe a 12mm or so.

Enjoy your new telescope, remember the mount head I think can in time be moved to sturdier legs.

Thanks for the tips, I have stool which I could you use. I won’t buy any eyepieces at the moment would like to get used to them. If I do find it’s not capable I’m sure I’ll get new legs. I’ve only managed to use it for an hour or  so but happy with it so far.

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The 25mm is generally usable it might just be how full the Moon is right now. I did see Saturn's rings with the provided 10mm in the same telescope mirror at x65 so it works ok too.

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18 minutes ago, happy-kat said:

The 25mm is generally usable it might just be how full the Moon is right now. I did see Saturn's rings with the provided 10mm in the same telescope mirror at x65 so it works ok too.

I did think that, when I get the chance I’ll see if it happens on other objects, everything was washed out because of the moon :) 

Edited by Dinoco

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16 minutes ago, happy-kat said:

The 25mm is generally usable 

I agree. I found the supplied 25mm usable however the 10mm, well that was not so great. Stars looked like blue-ish triangles. After I'd checked collimation, I bought some different EP's, problem solved. Perhaps I just had a dodgy 10mm.  

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1 hour ago, Redscouse said:

I agree. I found the supplied 25mm usable however the 10mm, well that was not so great. Stars looked like blue-ish triangles. After I'd checked collimation, I bought some different EP's, problem solved. Perhaps I just had a dodgy 10mm.  

I think mine was the same I’ll have another try. A lot of people usually say swap out the stock 10mm straight away because it isn’t great.

Edited by Dinoco

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On ‎28‎.‎02‎.‎2018 at 14:13, Dinoco said:

When viewing at the moon using my 25mm eyepiece I could see a blue and orange haze around the left and right side of the moon.

Sounds like atmospheric dispersion.

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Some vibration is normal and I just wait a few seconds for it to pass ... 

In windy conditions just find a dark corner out of the wind . Use the house or fence or shed as a windbreaker ?

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On the other hand I got a stock 25mm and 10mm with mine and both were champion little EP's, I still get the 10mm out and use it despite lots of other EP choices available.

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I often find that, whilst adjusting the focus knob, a star will tend to form a thin line, with most of the vibration along that line. If I make adjustments to minimise the thickness of that line, I find that I am close to focus when the vibration dies down.

I also find that my Dob is more user-friendly than my tripod-mounted Mak at similar magnification.

Geoff 

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I have not seen one of these scopes in the flesh so not sure what the focus knob is made of. If its plastic then you could use some glue to attach a piece of wood like a lolly pop stick to one. This would be the same as adding a clothes peg to a mak focus knob. It will allow you to fine tune your focus with the smallest pressure reducing vibrations.

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re: focusing with wobbles.  I found things greatly improved if I use a Bhatinov Mask.   You can google for a Bhatinov mask generator.  You print a template then carefully cut out the slots.  When you pop it over the front of the scope, you get a funny cross pattern that's quite easy to see when it's dead-on even with a few wobbles.

 

Re: colour shifts at opposite sides of the moon:  I'm sure that's colour aberration caused by 'cheap' eyepieces.    (terrestrial -) Photographers spend hundreds of pounds, even thousands, to get perfect lenses that end up weighing 1kg+.  A 50g eyepiece for less that £15 doesn't stand a chance. :-)  My BST Starguider 12mm is my best for eliminating that kind of colour problem and cost about £50.

 

Re alignment - further away is better.  I tend to go for a super-bright star.  If it's way off, the moon can still be hard to find so a distant tree-top during the day gets things 'close enough', ready for a proper night time star-adjustment.

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