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As I live in a fairly populated area I have not got any objects further than a hundred yards to align my scopes. My 8” Dob is ok as the wide vision field makes it quite easy to find objects. However my 127 Mak is a different story as the fov is quite narrow and it is difficult to align on anything. Has anyone come up with an alternative solution for finder scope alignment with a restricted distance.

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The moon is always a useful target as it's large and bright.

Might pay you to align on it while it is still up at a reasonable hour.

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15 hours ago, Geoff Barnes said:

The moon is always a useful target as it's large and bright.

Might pay you to align on it while it is still up at a reasonable hour.

I thought you had to use a static object to focus on ?

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Well once you've got the moon centred in the eyepiece it should only take a few seconds to adjust the finder. The moon is really not going to move to any significant degree while you get aligned.

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7 minutes ago, banjaxed said:

I thought you had to use a static object to focus on ?

I've used the Moon & Saturn/Jupiter for finder alignment. You just have to compensate for the drift.

Also a street lamp or TV aerial  around 50 metres distant has done the job.

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I've tended to use treetops around 150m away, centre in the scope then set the finder a smidge above which seems to work reasonably well for me. Fun when its a windy day tho and the trees swaying about. After that I'll tweak a little if needed once looking at the stars but found in the main little need to do much tbh

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I have bought an illuminated reticle eyepiece which should make aligning much easier, thanks for you advice.

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1 hour ago, merlin100 said:

Do finder scopes when focused relatively close up to something exhibit a form of parallax error?

Its best to align them with the scope optics using as distant an object as possible just for this reason.

 

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It depends what gets moved to change the focus. If the objective is moved to achieve focus, then the eyepiece will remain focused on the reticule and there will be no parallax. However if you move the eyepiece to get focus on closer objects, you’ll be moving the image plane away from the reticule and you will get parallax.

... assuming all the while there is no parallax at infinity.

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u can even do it on a building chimney, a street light hydro pole maybe evebn a building corner. its just to get close then at night u can get closer or near perfect

joejaguar

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You can also get it done roughly in the daytime on whatever the most distant object you can see - preferably TV aerial / chimney etc and then fine tune it at night on a bright star like Vega. i.e. if you can centre a star in the finderscope, as long as that gets it somewhere in the field of view with your lowest power eyepiece, you can then centre the star in the eyepiece & then tweak the finderscope to bring that into alignment.

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I have a 127 Mak. Quite new to me and I find the Celestron Autostar/Nextar, whatever, to be a bit of a bind. So after decades of not ever even mounting the finder scopes on my various scopes, let alone use them, I fitted and aligned the supplied Red Dot Finder (never used one before then).

Easy way in my mind was to center a bright star (think it was Rigel) in a low power eyepiece then adjust the finder to align Rigel with the dot.

It worked quite well. When working through GOTO alignment stars I centered my next target in the RDF and it was thereabouts centered in the eyepiece

40 odd years of fighting and resentment and it was over in 5 minutes! :) 

I feel dirty now... 

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The moon should do fine, alternatively could you get the scope upstairs and do it and then not knock it before you get it downstairs.  I find that you don't even need to be spot on with alignment, providing you know just how far out you are and in what direction.  Moon, a planet, a socking great big star (providing you can find one to start off with) anything can be used - just make sure you don't pick an aircraft!!!  LOL

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Agree with the others for using the moon if you can as it's a bright, easy target. I then usually fine tune mine using a star like Vega to get it spot on. Have to do this each obseving session as i always end up knocking it when carrying it outside...

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