A few more basic newbie questions

[Bogmonster]

Hey,

I got a bit of time last night to get used to my new scope even though it was a full moon so it was bright out, the views of the moon I got were amazing. First time seeing it through a scope myself and it's really impressive. But I have a few basic questions.

I have a Celestron Evo 9.25 and I've been hearing different things about aligning the red dot finder. Some people say do it during the day and others say to do it at night using the moon for best results. So I did it last night under a full moon (or mostly full) and my question is how exactly spot on should you be? I had the moon fully in my eyepiece but the red dot was in the moon but slightly to the top right on it's surface. I seemed to run out of room to move the dot using the thumb wheels and couldn't get it dead centre to match the eyepiece. Is this normal or is there a way to do it? I'm guessing it should be pretty exact especially for looking at small nebulae or clusters?

Also, is there any app or website you would recommend to see what the viewing conditions are like in my area (Ireland)? I've seen a bunch but some don't really make too much sense to me. I've generally been looking out the window, see stars and start getting set up. It's been very cloudy here the last week so I'm taking any opportunity I can.

Thanks for the help with these basic questions!

[Jasonb]

Hey there...

I'm afraid I don't have much of an answer for you regarding the alignment. I have occasionally struggled to get a finder aligned 'cos it's run out of room, as you say, but eventual with some gentle pushing and moving of the finder, and then using the alignment controls again, I usually get it pretty close. 

When I think I do have it aligned, and it's clear out, I'll do a quick test by looking at a bright star (so it's a pinpoint) and seeing how close it is then. Minor adjustments aren't too bad in the dark, but I do find it handy to do the first adjustment in the day light, assuming you can find something far away to aim at, just to get it close.

As for the never ending "Is it going to be clear?" I used to use the Clear Outside App, but to be honest its results weren't that accurate for me. Now I look at Met Eireann's website (for Leinster for where I am) and check out their forecast. For tonight it says...

"Long clear spells will develop tonight. Very cold with lowest temperatures of 0 and -3 degrees leading to widespread sharp frost and possible icy stretches. Mostly light northerly breezes."

So that's telling me there's a chance, for clear skies, but it depends how early they start to develop (I won't be up at 2am let me tell you!). Apart from that, it's like you say, sticking your head out a window and seeing how clear it is! I haven't really got a chance to "plan" many observing sessions, instead they tend to happen when I noticed it's clear out!

[Cosmic Geoff]

1 hour ago, Bogmonster said:

I have a Celestron Evo 9.25 and I've been hearing different things about aligning the red dot finder. Some people say do it during the day and others say to do it at night using the moon for best results. So I did it last night under a full moon (or mostly full) and my question is how exactly spot on should you be? I had the moon fully in my eyepiece but the red dot was in the moon but slightly to the top right on it's surface. I seemed to run out of room to move the dot using the thumb wheels and couldn't get it dead centre to match the eyepiece. Is this normal or is there a way to do it? I'm guessing it should be pretty exact especially for looking at small nebulae or clusters?

Can't help much with the red- dot finder. There ought to be enough adjustment range. If there isn't, fiddle with the finder mount in daylight and see if you can shift it or pack under one end.  Good news - you only need it once or twice a night, to set up the GoTo.  Red-dot alignment needs to be exact enough to get your GoTo alignment stars in the field of the low-power eyepiece - after that it doesn't matter.

 

1 hour ago, Jasonb said:

So that's telling me there's a chance, for clear skies, but it depends how early they start to develop (I won't be up at 2am let me tell you!). Apart from that, it's like you say, sticking your head out a window and seeing how clear it is! I haven't really got a chance to "plan" many observing sessions, instead they tend to happen when I noticed it's clear out!

I use FLO's 'Clear Outside', and the Met Office forecast - sometimes they actually agree. 🙂

[Carbon Brush]

With a long focal length scope like yours, you have a narrow field of view which means good finder to scope alignment is essential.
A lot of people find more than one finder scope is useful - or even essential.

My Intes MN78 is shorter FL than your Celestron.
I have used a 9x50mm finder for years, more recently upgrading to a 60mm finder.
I also have a Rigel quickfinder RDF. I regard this as a first try device if the goto system has got lost.

HTH, David.
 

[Bogmonster]

1 hour ago, Jasonb said:

Hey there...

I'm afraid I don't have much of an answer for you regarding the alignment. I have occasionally struggled to get a finder aligned 'cos it's run out of room, as you say, but eventual with some gentle pushing and moving of the finder, and then using the alignment controls again, I usually get it pretty close. 

When I think I do have it aligned, and it's clear out, I'll do a quick test by looking at a bright star (so it's a pinpoint) and seeing how close it is then. Minor adjustments aren't too bad in the dark, but I do find it handy to do the first adjustment in the day light, assuming you can find something far away to aim at, just to get it close.

As for the never ending "Is it going to be clear?" I used to use the Clear Outside App, but to be honest its results weren't that accurate for me. Now I look at Met Eireann's website (for Leinster for where I am) and check out their forecast. For tonight it says...

"Long clear spells will develop tonight. Very cold with lowest temperatures of 0 and -3 degrees leading to widespread sharp frost and possible icy stretches. Mostly light northerly breezes."

So that's telling me there's a chance, for clear skies, but it depends how early they start to develop (I won't be up at 2am let me tell you!). Apart from that, it's like you say, sticking your head out a window and seeing how clear it is! I haven't really got a chance to "plan" many observing sessions, instead they tend to happen when I noticed it's clear out!

Cheers! I'll give it another go during the day and make sure. I had it pretty close through my lowest power eyepiece. I suppose it's just a matter of trial and error and getting used to it. 

I'll check out the app too. I'm in the same boat as yourself, I don't plan my sessions out, I look outside and see a few stars and then get my stuff together.

[Bogmonster]

32 minutes ago, Cosmic Geoff said:

Can't help much with the red- dot finder. There ought to be enough adjustment range. If there isn't, fiddle with the finder mount in daylight and see if you can shift it or pack under one end.  Good news - you only need it once or twice a night, to set up the GoTo.  Red-dot alignment needs to be exact enough to get your GoTo alignment stars in the field of the low-power eyepiece - after that it doesn't matter.

 

I use FLO's 'Clear Outside', and the Met Office forecast - sometimes they actually agree. 🙂

Another vote for Clear Outside so I'll give it a go. 

I figured once you get the scope aligned then you're good to go since the go to mount will take me where I need.

[Bogmonster]

4 minutes ago, Carbon Brush said:

With a long focal length scope like yours, you have a narrow field of view which means good finder to scope alignment is essential.
A lot of people find more than one finder scope is useful - or even essential.

My Intes MN78 is shorter FL than your Celestron.
I have used a 9x50mm finder for years, more recently upgrading to a 60mm finder.
I also have a Rigel quickfinder RDF. I regard this as a first try device if the goto system has got lost.

HTH, David.
 

Thank you! I've heard people saying the finder isn't great on these but I'll keep going with it for now. I'm still a total novice here so I'm constantly learning.

[bosun21]

It’s quite a simple process. All you need to do is place a thin shim under the finder shoe to compensate for the lack of adjustment. This will bring it back into alignment with your telescope. I also always align my finder with a bright star and an illuminated reticle eyepiece.

[Bogmonster]

51 minutes ago, bosun21 said:

It’s quite a simple process. All you need to do is place a thin shim under the finder shoe to compensate for the lack of adjustment. This will bring it back into alignment with your telescope. I also always align my finder with a bright star and an illuminated reticle eyepiece.

Thank you! I was thinking of a shim of some sort but I wasn't sure if that would throw the whole thing off. I didn't even know you could get an illuminated eyepiece. 

[Sunshine]

Hello! I have never known anyone to use the moon at night to align their finder scope as the moon is such a large and bright object which the red dot can be lost on. Also, you would want it aligned more precisely than that as picking a spot on the lunar disc to align to would be cumbersome. Precisely aligning a finder should be done during the day on a distant target like a smoke stack or top of telephone pole where objects are not moving relative to the telescope. Any point on a distant stationary object will do, slimply centre said object in your eyepiece (medium power eyepiece is good) then without moving your telescope, adjust the red dot on the finder so it is dead on the same spot you’re looking at in the eyepiece. 

[Mr Spock]

I use a Baader SkySurfer and find that is always at the end of its travel. It just works, anymore and I'd have to make alterations to it.

I align it either by using the moon or, a bright star.

[Spile]

It can be useful while you get used to it, to align the finder on a distant tree or antenna in daytime.

[Bogmonster]

Thanks again guys. I'll do it again during the day and see how that goes. How far away should my target be? 

[Carbon Brush]

As far as possible!
If you can get 100x the scope focal length, that is a good number.
But in an urban area, you may have to compromise.
Unlike observing, you can do this from an upstairs window on a wobbly floor.

 

[Jasonb]

As far as possible really! The most distant "point" you can see, be it the top of a tree, a church spire, a telegraph pole etc. You can find tune the alignment at night with a bright star, but getting it close at day time is just easier. It's never going to be spot on, but I think your Scope has some sort of Go-To/StarSense automatic system, and someone said earlier in the thread that it only has to be aligned enough to help you get the GoTo working...

[Naughty Neal]

The dot finder that came with my z130 worked fine with plenty of adjustment.  I tuned mine in during the day by using the scope to centre some pidgeons in a tree some disatnce away then used the dot finder to home in on the pidgeons ( excuse the intended pun).  After that I aligned the dot finder on a  dangly bit on a on an electric pylon in the distance and the centre of the scope view appeared pretty much  central.  The real proof of the pudidng is at night when one wants to locate a dso.

Edited March 9, 2023 by Naughty Neal

[Pixies]

Aligning the finder during the day is much easier but as you get to know your scope, you'll know whether you need to fine-tune the finder alignment each night. If that's the case, hopefully it'll only ever be a little bit off, so you can align just using a bright star.

With a few nights' experience, you'll know what you need to do. It will depend on how you store the scope, whether you remove the finder each time, etc.

[bemak187]

If it is the basic Celestron Star pointer red dot that came with your rig then these are pretty poor.  They have a well documented reputation for having limited adjustment and just generally being poor quality.  There are workarounds of making a shim etc but on the whole it is just not a great finder.

[AstroMuni]

On 06/03/2023 at 11:22, Bogmonster said:

Some people say do it during the day and others say to do it at night using the moon for best results.

I would recommend you get it coarsely aligned in the day using a distant object such as a TV antenna. The cross bars on the antenna really help. And then at night you can do a better alignment with an object that doesnt move too much (pole star is a good one).

[Guest]

On 07/03/2023 at 02:53, Bogmonster said:

Thanks again guys. I'll do it again during the day and see how that goes. How far away should my target be? 

I do my alignment during the day light.  It is just so much easier.  As to how far away, the further the better.  I have two alignment points.  The first is 400 yards away the second is the flashing light of a cell tower two miles away.  I use my variable eyepiece for this usually and start at 24mm and then drop to 8mm.  This gets the finder and the scope looking in the same place.  Then when it gets dark enough i align the laser to the finder scope.  If I do everything just right the object i am looking at will be pretty close to centered and the laser will be right under it.  As the saying goes, aim small miss small.