Finder scope issue

[startreker1]

I have an Apertura 8" Dobsonian, and I have gotten it collimated, but am having problems with the attached finding scope not being accurate to what I am seeing in the focuser. Is it true that if I add the Rigel Quick finder I bought I will have an easier time finding the targets I want in the sky, and should I be alright then with the telescope showing it accurately then too, as long as the telescope is collimated correctly? It has been frustrating seeing the object in the center of the crosshairs in the finder scope, but not seen in the focuser for viewing. Also really hard just trying to aim the finderscope to find the object in the sky. I have to guess alot. Maybe this is where a computerized scope would have been easier I think.

Edited August 17, 2019 by startreker1
extra letter

[Steve Clay]

You need to align the finder with the view in eyepiece. This is best done in the daytime with a distant object. 

Steve

[Buzzard75]

You need to get the object in the eyepiece of the telescope first and then adjust the finderscope until it is in view. The process would be the same when using a Rigel Quick Finder or a Telrad. It's recommended you find an object in the distance to start and align the finderscope to the telescope. You can then fine tune the alignment with an object like a star or planet.

[banjaxed]

Sounds like you have not lined you scope up with the finder scope. Pick a lamp post or tv aerial as far away as possible and line up your scope on the target, then line up your finder scope on the target and that is all you need to do. Make sure you have the target in the centre of the scope and finder.

looks like you beat me to it 🙂

Edited August 17, 2019 by banjaxed

[startreker1]

Thankyou! I also found a beginners video that said to do that too, so I will. My instruction manual I got is really useless, except for putting it together. I am getting used to trying to eyeball the object in the sky first with figuring out where to center my scope for finding it. Still working on that. maybe a computerized scope would have made that much easier for me.

[Pankaj]

I consider a dob to be an astronomers best friend for the sheer leverage we get in terms of setting it up and of course the aperture. Even if you get a computerized mount my friend, polar alignment, star alignment etc; will come as added baggage to your hobby. Go slow to enjoy this hobby to its fullest. I have owned a dob for many years and believe me, the 8'' you have will show you some extremely pleasing views.....depending upon how dark your skies are. My 10'' dob gives outstanding results when I view from bortle 2 skies. Best of luck with your new hobby.

[Chefgage]

I align my finderscope and telescope in the daytime ( make sure it is pointing no where near the sun). I have a church spire about a 1/4 mile away which is the furthest point i can see from my house. So with the 20mm eye piece inserted i center this spire in the telescope eye piece. I then adjust the finderscope using the adjuster screws so the spire is the centet of the finderscope.

The next thing to do is to make it a bit more accurate by then using a higher power eye piece such as a 4mm (or whatever came with the scope). Center the spire in the telescope 4mm eye piece and again center the spire in the finderscope. 

Providing you do not knock the finderscope before it gets dark whatever you see in the finderscope will be centered in the telescope eye piece.

Think about getting a rigel quick finder as well. That way you can use all three to find your targets. Makes the process a lot easier.

[JamesF]

Very much agree with this.  Do as much setting up as possible during the day.  It means you can see what you're doing more easily, and you're not wasting time fiddling about trying to get kit to work (and usually rushing to try to get through it) when you could be taking advantage of clear sky.  Just keep the telescope from pointing anywhere near the Sun, as Chefgage says.

James

[Cosmic Geoff]

Devices like the Rigel or red dot finder complement rather than replace an optical finder as they let you aim the telescope assembly accurately enough to pick up the desired object readily with the finder. You can also aim a red-dot finder at an apparently blank area of sky.

You will get along well enough without GoTo so long as you are viewing objects bright enough to show up in the finder.  GoTo really comes into its own for fainter objects, or for speeding up the finding of a series of objects once the GoTo is successfully set up.

[Captain Scarlet]

All the above. However if like me in London you have no view of anything sufficiently distant to line up on, you can get rough finder-alignment by, say, aiming the main scope at a feature of your house, then aiming the finder scope at a point the same distance above and to the side of that feature as the finder is above and beside your scope.

I find that even that rough alignment is better than vainly trying to find a star blindly at night with a relatively high magnification scope, and then risking aligning the finder to a different star (been there, done that).

[Science562h]

You need to line-up the finder 'scope. (1) Aim, at something in focus, with your telescope & then, (2) adjust your finder 'scope. Center your finder 'scope, with, what you see, trhough the EP. I  find Apertura's finder exceptionally good & better than Celestron & Orion's shaky ones. There isn't much comparison at all there. Apertura's hold's accuracy. Id'e stick, with the 8x50mm finder 'scope, it's awesome for viewing fields. If you just 'wanna star hop & cut down on finding time, put on a red dot. though. A GOTO 'scope wouldn't make a difference because you have to find alignment stars.  

Image 1. Apertura 12 inch.

Edited December 29, 2019 by Science562h

[joe aguiar]

yes the rigel once u align it is MUCH easier to use to find items. You will know perfect where your are pointing to where a 6x30 regular finder will blow up the image and if you have 10 stars in the finderscope which one is the one you want? which can be a pain in the beginning. You wont have this issue with the rigel where you point it is where you are looking at.

joejaguar

[John]

18 hours ago, Science562h said:

You need to line-up the finder 'scope. (1) Aim, at something in focus, with your telescope & then, (2) adjust your finder 'scope. Center your finder 'scope, with, what you see, trhough the EP. I  find Apertura's finder exceptionally good & better than Celestron & Orion's shaky ones. There isn't much comparison at all there. Apertura's hold's accuracy. Id'e stick, with the 8x50mm finder 'scope, it's awesome for viewing fields. If you just 'wanna star hop & cut down on finding time, put on a red dot. though. A GOTO 'scope wouldn't make a difference because you have to find alignment stars.  

Image 1. Apertura 12 inch.

Aperturas are made by GSO. The GSO 8x50 finder is pretty much exactly the same as the Celestron and Orion ones. They are designed and work in exactly the same way. I've owned all thee types.