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After a decade of observing through binoculars and occasionally peeking through other people's telescopes I finally bought a 102 mm Mak.

I've used it three nights in a row and I'm having a lot of fun with it. However, the 6x30 finder scope is really hard to use! I set the tripod low enough that I can observe either sitting down or bending over to the eyepiece. This way it also helps with stability. But when searching for targets up high in the sky it's a gymnastics session just to squat under the finder, maintaining equilibrium while holding the mount's hand controller, a sky atlas and a red light. After a minute or so my legs start to hurt and the desire to find that particular object diminishes. As you may now imagine, I'm not particularly of the athletic type. Also I'm not yet comfortable with the inverted view, even though I admit that I may get accustomed to it eventually. I have a go-to mount but there are situations where I need to point manually.

So I'm already thinking about replacing the finder scope.

I see there are finders with a 90 degree diagonal and at first sight that seems to solve my main problem.

Some observers seem to prefer red point finders and telrads but you still have to get under the telescope to use them, right?

Another question: how important are optical differences between models? I guess that given the function of the finder scope comfort and ease of use are the main concerns...

Any suggestions? TIA!

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Welcome to the SGL.

Someone with a Mak will offer more advice with the fitting of a suitable finder scope, but a quick look at the 127 looks like its possible to fit a Telrad, maybe on a riser, but will still be awkward when trying to look straight up, but  the image through the Telrad is the same as naked eye observation of the sky.

Looking straight up is probably the shortest route of visibility through the atmosphere? The shorter the route the better the image, under the right conditions?

A RACI ( Right Angle Corrected Image ) finder  may  suit you better for the vertical observations. Lets see what other users have to say and use?

I have two finders fitted on my scope.

Edited by Charic
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I do like Telrads, but I agree that they work best on Dobs or long refractors where you can mount them far enough up the tube to be comfortable to look through. I have a Rigel on my SCT and find it awkward to look through too.

I would suggest a 9x50 RACI Finder which will be comfortable to use whilst showing a corrected image which makes finding things more intuitive.

Something like this...

http://www.firstlightoptics.com/finders/skywatcher-9x50-right-angled-erecting-finderscope.html

They do come up used on AstroBuySell too if you don't want to buy new.

Stu

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I forgot to mention that I also found that the finderscope gets out of alignment with the slightest tap, does this happen with other types of finder?

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Hi ntc and welcome to SGL :)

You can get finders that not only have a 90o diagonal but also invert and reverse the image so that you see the same view as looking up to the sky. It's called a "right angled correct image" finder (or raci). Using one of these you can set your scope so the observing end is at a comfy height (sitting or standing) and just look in the side without getting under the scope. Makes viewing the zenith a lot easier. Hth :)

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+1 for the RACI. It makes life so much easier. Well, that's an exaggeration - it makes using the scope so much easier. :-)

Edited by Floater
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Not having used a RACI myself............If I fitted a RACI the far side of my standard  9x50, in-place of the Telrad, and rotated the finder eyepiece in order to reach the finder by leaning over, do I still have a corrected image, or is there some rotation? 

The link Stu supplied, the eyepiece is vertical, If I rotate that to 90° does the image turn with it ?

Its worth a punt, as so many folk highly recommend the RACI. Its not the first Telrad I have sold? Nothing wrong with the Telrad, but I need glasses to use it, and it only gets used from my darker site!

Edited by Charic
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.......phone rang, and lost the ability to edit/finish my text?

Its the 9x50 that would go in favour of the RACI  not the Telrad!   The emphasis on placing it the 'other side'  was to emphasise  reach and  rotation?

My Dob produces an inverted image, but looking at aerials on roof tops, the image is also angled, due to the focusers alignment with the angle of the OTA!

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A Telrad will sort out finding stars,dso's ect it come with base so when removed and put back on, it remains aligned.....there are Telrad maps free to download and CdC and Stellarium both the feature the Telrad circles on their maps...

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...no reply to #7?

RACI

If you approach and view  in the direction of the black arrow,  then I assume a corrected image, but  If  you approach 90° offset to the parallel,  is the image offset? 

Considering a purchase, but this scope will be no good to me If  I remain seated and need to approach the finder from the side  ?

ntc, consider the 9x50 finder over the 6x30

Edited by Charic
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...no reply to #7?

If you approach and view  in the direction of the black arrow,  then I assume a corrected image, but  If  you approach 90° offset to the parallel,  is the image offset? 

Considering a purchase, but this scope will be no good to me If  I remain seated and need to approach the finder from the side  ?

ntc, consider the 9x50 finder over the 6x30

I have a couple of 9 X 50 finder scopes, they have never been out of there boxes after i tried the first one on my first scope and then got a Telrad......

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Tinker1947.....thanks. I have no issues with either the standard 9x50 finder or my Telrad, they both work fine, favouring the 9x50 over the Telrad for light polluted sites?

My issue is understanding the alignment of the RACI. Does the eyepiece in the finder scope rotate to keep the image vertical, when viewing from the side of the finder scope! that's what I'm trying to ascertain?

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If you look straight through the raci and turn it on axis - then the image turns with it. But it always remains correct both top to bottom and left to right. Other finder types do exactly the same except the image remains inverted and reversed left to right - but it still turns as the finder turns. Hth :)

(The eyepiece is fixed on the Orion and S/W 9x50. I also have an Altair 12x60 which has an eyepiece which is used to focus only - ie doesn't turn the image at all)

Edited by brantuk
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I use a Rigel Quikfinder on my WO ZS71 (420mm focal length, so pretty compact and not enough room for a Telrad) - I find it much easier than a finderscope, as it seems so natural to look at a star with both eyes but with the reticle overlayed over the view from my dominant right eye

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....cheers brantuk. 

Seems like I'm making this more difficult than it really is , but still trying to grasp one issue?

Say your sat at your table? The finder is sat in front of you, on the table, with the eyepiece to the right,  pointing up to the ceiling,  and the finders  objective is to your left.

If you just lean forward and look down the eyepiece,  90° from the finders axis, what is the result?

I cant see that you can get the same image orientation, going by the angles indicated from my image above.

Edited by Charic
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Effectively you're looking through the finder from the side in that scenario. So right is twisted upwards and left downwards 90o. And bottom is now right and top is left. If you just look straight forwards without a raci then tilt your head 90o left - that is the view you get.

In reality though the finders eyepiece position on a scope gets moved around during the night. As the scope gets turned up and down at different angles the finder can be a stretch to look through - so I twist it down and tweak the alignment with main scope to make it easier to view through.

I'll bet that's all clear as mud lol :)

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Yup - it's all down to personal preference and ease of use. I just couldn't get on with straight through finders myself - neither the view, movement, nor the arrow key muscle memory (or rather lack of it). Raci's changed my life (astronomically lol). But whatever works for you is the best solution. :)

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