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Problems with finderscopes


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I know it has been mentioned before about people struggling with finderscopes so this is just a post about what i have found when trying to center a star in the finderscope.

I have a skywatcher 200p with a 9x50 finderscope. I have had no problem lining up the finderscope with the telescope. My problem lied with seeing a star in a constillation and then getting that star in the center of the finderscope. I sort of got the hang of using the technique of using both eyes to superimpose the two star images you see. But as i have quite bad light pollution the stars i often see are quite dim making this technique difficult.

I then decided to get a rigel quickfinder to try and  make the process of getting stars tovthe center of my telescope easier.

If like me you were struggling doing this I certainly recommend getting a quick finder. It makes finding targets so much easier. 

What I do is use the quick finder first by getting the star in the middle of the illuminated circles. I then look through the 9x50 finderscope to fine tune the star to the center of the cross hairs, then when i look in the eye piece, there it is :) 

I have mounted the quick finder on top of the 9x50 finderscope which makes looking through the quickfinder alot easier on my back/neck.

 

IMG_1484.JPG

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1 hour ago, Astro Imp said:

I like the idea of mounting the Quickfinder on the finder to raise the viewing position. Great idea.

I did wonder how it would work with it being so high. Its works as it should and its much more confortable to look through as its raised up.

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That's a great idea!  I recently got a QuickFinder for my dob and struggled with a position to put it.  In the end I placed it so it's just below the focuser.  Not an ideal position but it works.  Good thing the QF is supplied with two bases so I think I'll definitely try installing a base on my 60mm RACI.

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3 hours ago, Davesellars said:

That's a great idea!  I recently got a QuickFinder for my dob and struggled with a position to put it.  In the end I placed it so it's just below the focuser.  Not an ideal position but it works.  Good thing the QF is supplied with two bases so I think I'll definitely try installing a base on my 60mm RACI.

Try it, its certainly confortable in that position

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On 5/5/2017 at 04:55, Peter Drew said:

The "perfect" solution!    :icon_biggrin:

I went two steps further.  In addition to the finder scope and telrad/quickfinder (both mounts are on the scope depending on my mood), I added a green laser sight and digital setting circles.  Generally, the laser is good enough to get the star in the center of my widest field eyepiece.  If there is a lot of scatter in the atmosphere (high humidity), I'll use one of the unit power finders instead.  If I'm searching for small, dim objects, I'll then star align the DSCs.

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I use pretty much the same finder arrangement with my 12" dobsonian except that the Rigel is alongside the optical finder and the optical one is a RACI. Together with a good star atlas, this approach has worked very well for me :icon_biggrin:

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It's a great idea chefgage. I have an 80mm RACI Finder, which also has two Telrad bases and a Rigel base on it! Think I was bored at the time, but it does allow a combination of the Telrad circles and finderscope to be used easily at the same time which works very well...as you have found! :) 

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Same here. Talrad plus Right Angle (RACI) finder. Straight through finders are a compete pain in the neck / back! But, RACIs can be difficult to aim. No probes with this solution.

You can get away with a £10 Red Dot finder. It is acurate to get the desired star into the finder fov.

Paul

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Everyone will have a different view (excuse the pun) on what's best and how best to use their particular finder scope, but it looks like we all have an issue or two, and  I keep seeing the use of multiple sighting systems, yet I find  using my straight through 9x50 with both eyes open is the easiest method to obtain the target, but not necessarily the most comfortable finder, when the telescope reaches zenith, especial from my seated position, but its something I can overcome and still have success with the results, with light pollution too!

"But as i have quite bad light pollution the stars i often see are quite dim making this technique difficult"  I don't understand how a quick finder can improve this situation, especially any dimness, because if the Rigel works similar to a Telrad i.e. non-magnifying, then what you see is what you'll get, as if using your eyes alone! but if the system works for you, then so be it, after all, its what satisfies the needs of the end user.......... its just my opinion!

I've used the Telrad, thinking it would be of some benefit at a darker site, because I may not see the 9x50 reticules, but this is not the case anymore. The Telrad works as a finder,  but my issue was focusing on the reticles superimposed over what I was targeting, I could see three sets of concentric 'Bulls-Eye' rings, simply because my vision needs some  minor correction for distance viewing, therefore the 'Bulls-eye' was less than a perfect image when viewed without glasses, which are not used when looking through the eyepiece in the telescope. 

I also feel that some folk could do better by just using a low-powered eyepiece to find their subject matter, rather than agonising over which extra finder scope is best, or where to position the actual finder after purchase?  Telrad's have risers, if/when required, but the Rigel has  already 'risen'  due to its  design ( it looks taller ) but  who needs a riser when you have a 9x50!!

At least a low-powered eyepiece will offer some magnification and contrast,  adding some detail to  your visual clues,  but its still  something you'll still need to practice and  get comfortable  with, especially without image correction? so back to the beginning for some folk,  which one is best, where shall I put it? 

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8 hours ago, Dave In Vermont said:

Louis D. - I was just about to ask where to fit my 'greenie' on the Telrad! :p

Unreal!

Dave

The great thing with laser sights is that they can be mounted literally anywhere on the OTA or mount that points in the same direction.  For my smaller scopes, I have my laser mounted on the guiding handle of my DSV-1 so it's there with any OTA I choose to mount that night.

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I read the OP and felt most gratified that it wasn't just me.

I've gone the two finders route, and got to try them the other night.  There is a guy in Poland on ebay 3D printing dual finder mounting brackets for the Skywatcher 200P and I got the SW red dot finder to go with the RACI finder I already had (thanks to the SGL classifieds) the other night got them both attached, and although I need a little more downwards angle on the red-dot I realised how far off it was at the angle I had it and just compensated for that when I found things (it wasn't far out).  I had the most successful finding so far.  The red-dot got me roughly I need to be and put the object of interest in the RACI, then the object centred in the RACI (which was bang on with the scope), put to object into my 25mm and off I went.  I am convinced that with two finders I now have this finding lark sussed.  Def. the way forwards for me.

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20 hours ago, Louis D said:

The great thing with laser sights is that they can be mounted literally anywhere on the OTA or mount that points in the same direction.  For my smaller scopes, I have my laser mounted on the guiding handle of my DSV-1 so it's there with any OTA I choose to mount that night.

The trouble with Lasers is that they are getting a bad press in the UK at the moment due to trouble makers shining them at aircraft.  I didn't personally want to use a laser even though I've heard they are pretty good.

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12 hours ago, JOC said:

The trouble with Lasers is that they are getting a bad press in the UK at the moment due to trouble makers shining them at aircraft.  I didn't personally want to use a laser even though I've heard they are pretty good.

Yeah, I don't even light them up if I hear a plane.  I'll use a unit finder until they pass.  I'm actually not that far off the approach path to an international airport.  The UK also limits sales of lasers to have an output of 1mW rather than the 5mW allowed in the US.  I'm not sure if you could see it as easily at 20% of the power.

Can folks in the UK buy the latest image intensifiers from non-US sources?  We can buy US-made cutting edge ones, but we can't sell them to buyers outside the US or take them out of the US on a trip.

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On ‎07‎/‎05‎/‎2017 at 21:27, JOC said:

I am convinced that with two finders I now have this finding lark sussed.  Def. the way forwards for me.

FWIW I got a chance to try them out again last night - nothing else seemed to be working, but again I was at least finding the few things I aimed at within a few moments. 

I'm having to learn how to see the red dot through the finder - it sometimes takes me a short time to get the angle right and actually see the red dot on the screen (it also isn't quite spot on with the telescope as I run out of adjustment, but its fairly close), but once I've done it and got the RDF roughly on target the magnified RACI finderscope also then has the object in its view.  My RACI is spot on with the telescope so once I've got the object centred on the RACI cross hairs, well....Bob's my uncle (well actually he's my dad and my brother!!  Both called Bob!).

I don't think any astronomer can have any more problems finding things than I had, but if anyone is looking for a recommendation a cheap RDF and a RACI on a dual mounting arm has certainly solved things for me.

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