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How many of you all use two finders on one scope?  Sometimes, especially when looking almost straight up I have difficulty figuring out what my Z10's Right Angle Finder is pointing at even if I go hug the ground under it and look along the tube.

I was considering raiding the gun scopes and mounting one to my tube then remembered I have a non magnified finder attached to a toy refractor in back of the garage.....my next thought wandered to thinking before I drill too many holes them Telrad's have the field of view circles and are probably the most useful to use with Stellarium.

Is a Telrad probably the best compliment to my RAF?

If I have more patience will I get used to where it is pointing?

How do these mount to the OTA?  Screws?  Adhesive?  I am not above drilling extra holes I suppose but if there is a more civilized way....

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I have (nearly) the same as bunnygod, a telrad and RACI. I don't know how I ever got in without the telrad before the acquisition. Some people rave about the Rigel Quickfinder too (I've never tried it).

directly overhead with a dob is pretty hard, I was told this when I first got it, but if course you have to try it for yourself :)

 

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You need a reflex finder to see where you're looking.  I have mounted an RDF on the arm of my RACI finder.  It's held in place very nicely with a couple of cable ties.

(Tried a straight-through finder (with double inversion) and couldn't take to it!)

Doug.

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Yes anything that helps find stuff. I have a RDF and a RACI on my SCT 9.25, the RDF to get in the general ball park area and the RACI to nail it down. This is based on the fact that I need all the help I can get !

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I have used the Rigel Quikfinder and the 6x30 finder. The Rigel works very well for finding your naked eye guide stars. It can be pasted to the scope with double sided tape. I have used the dual finder base, which also works, but adds some extra weight to the scope. On my new C8 I will install it in some other way.

I guess I needed the reddot finder especially because the 6x30 finder shows very little and my scope has a narrow field of view. It was impossible for me to find my guide stars by looking along the scope and looking through the finder. This could be easier with a wider finder scope. The combination of those 2 finders works very well.

I have now purchased a 50mm finder, but as it has become summer and the days are very long, as well a being occupied with other things the last many weekends, I haven't even used it yet.

For Rigel vs Telrad, I would let it depend on the scope size. Small scope = Rigel. Bigger scope = Telrad.

The Rigel is so short that if you look through it from the side, you see the red dot in a slightly different place than when you look straight at it. I think the Telrad (that I have never used) forces you to look more into the same direction, because of it's length.

With the Rigel I haven't experienced any dew issues, in contrary to with my 6x30 finder. The Telrad is apparently a bit more prone to it and might need a home made dew cap.

Edited by Linda
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Hi

The Telrad/RACI combo is about all you will need to help you find almost anything in the night sky. As has been said above the Telrad comes with double sided tape on the base to allow for easy location on your scope. Just make sure the surface is clean and dry before sticking it and it should hold it firmly for many years. The Telrad on my 10" Dob has stayed on for 6  years just with the sticky tape alone. :) 

 

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As per many above, I use 2 finders on my 12" dob. I have optical and RDF finder options for my refractors but I tend to use either / or with those depending on my targets. Here is the top end of my dob with the Rigel Quikfinder and the 9x50 RACI optical side by side:

 

12finders.JPG

Edited by John
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I also use a Rigel, RACI combination on my 8 inch Dob. I found that using both has made much easier to star hop in search of targets. Why the Rigel rather than Telrad? Purely because of the Rigel's smaller footprint. The Telrad is much more bulky but does have the advantage of an extra setting circle of 5 Degrees.

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1 hour ago, Stub Mandrel said:

I have the tiny finder that came with my scope plus a 50 x180mm scope that has a better FOV and a brighter image but no crosshairs (until I can find a cheap 20mm 0.965" with them)

can you get 1.25" eyepieces with crosshairs? I've got a 0.965 to 1.25 adapter you can have, if they do.

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31 minutes ago, rockystar said:

can you get 1.25" eyepieces with crosshairs? I've got a 0.965 to 1.25 adapter you can have, if they do.

You can easily make one from a spare Plossl - just glue two pieces of very fine fishing line (or indeed your own hair if you have any) across the field stop, having removed the silver barrel to gain access. I did this with an old Plossl to make a micrometer eyepiece. If your eyes are perfect then the hairs will be in perfect focus when you look through the eyepiece. My eyes are far from perfect and I needed to position the wires just a little bit further in than the field stop, which I achieved by glueing in a washer or two before applying the hairs. Having done all that I never actually use it.

As to two finders, years ago I mounted my 80mm frac on my 8" dob, and because the frac gave upright left-right inverted views I also needed the 30mm finder on the frac so I could star hop by map. It was all too much trouble to be worth it, I found a better solution was to get a better map. These days on my 12" I use the stock 50mm finder to get myself aimed at a bright naked-eye star. I then use a 32mm eyepiece in the main scope, and a very detailed map (12 mag limit), to get myself to the exact location, then (with my eyepieces mounted on a turret) I move to a zoom and search for the object. Works for me.

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I've tried using a finder scope, but never could get the hang of it.  When using my AT72ED, I already get a 6+ degree field with a 40mm Meade 5000 SWA in it.  With my dob, I get nearly 3 degrees with it.  That, and the weight kept throwing off my scope's balance.

On the dob, I either mount a Telrad or Rigel Quickfinder, depending on my mood.  On the refractor, I can't fit a Telrad, so I use the Rigel.

I'm getting too old to twist around properly for more than a few seconds.  That, and my presbyopia makes it difficult to see both the near circles and the distant sky at the same time, despite the circles supposedly being projected at infinity.

Because of that, I permanently added green laser sights to each scope on Picatinny rails.  They have momentary switches on coiled cords.  It's so easy now to instantly sight in the scope on a naked eye target or patch of sky.  I still use the Telrad or Rigel if parallax with the laser is giving me issues to regain a target at high powers so I don't have to switch back to a lower powered eyepiece.  Just keep an eye out for aircraft so no one can try to claim you were trying to blind a pilot.  If they are anywhere nearby, I hold off lighting up the laser.

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6 hours ago, rockystar said:

can you get 1.25" eyepieces with crosshairs? I've got a 0.965 to 1.25 adapter you can have, if they do.

Thanks, but I made the scope by fitting a 180mm  (achro) objective to a cheap 300mm scope and drastically shortening the tube. To use an adaptor I'd have to shorten the tube a lot more and it wouldn't really work.

Finder Scope.JPG

I think I will have to look round for a plossl ep, the one I have has its focal point INSIDE the glassware.

I did have a raci prism with that cheap scope but it was clear that with shortening it would cause vignetting, also I find it easy to use a normal finder as I just turn the map upside down.

<edit> I see that buying a 20mm plossl will probably cost me more than buying a 9x50 finder off Astroboot!

Edited by Stub Mandrel
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11 hours ago, MarkVIIIMarc said:

How many of you all use two finders on one scope?  Sometimes, especially when looking almost straight up I have difficulty figuring out what my Z10's Right Angle Finder is pointing at even if I go hug the ground under it and look along the tube.

I just bought a Z10 2 weeks ago (z10 bros, fistbump) and I feel your pain so bad. Ursa Major is directly above me and I've spent the better part of 2 nights trying to figure out if I'm even looking at the right area.

 

The more I read, the more I think I'm probably gonna double up with a telrad, too.

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19 minutes ago, Negatron said:

I just bought a Z10 2 weeks ago (z10 bros, fistbump) and I feel your pain so bad. Ursa Major is directly above me and I've spent the better part of 2 nights trying to figure out if I'm even looking at the right area.

 

The more I read, the more I think I'm probably gonna double up with a telrad, too.

Seriously, get a green laser sight off of ebay and a Picatinny rail to mount it to.  Your back and neck will thank you.

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1 hour ago, Louis D said:

Seriously, get a green laser sight off of ebay and a Picatinny rail to mount it to.  Your back and neck will thank you.

Are these types actual lasers you point into the sky? Are they actually OK to use? They have a metric tonne of red tape in the US and in the off chance the beam hit a plane they scramble police choppers because its a federal offense...

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1 hour ago, Negatron said:

Are these types actual lasers you point into the sky? Are they actually OK to use? They have a metric tonne of red tape in the US and in the off chance the beam hit a plane they scramble police choppers because its a federal offense...

Yes, actual lasers.  Many amateur astronomers are using them.  No red tape to my knowledge as long as they are under 5mW.  Yes, you must be situationally aware of aircraft in the area when using them.  More than 5 or 10 feet away from the axis and you can barely see them, so neighbors are unlikely to even notice you using them.  However, don't use them at star parties where people are imaging.  You might put a bright green line in one of their images if near enough to them because imaging is far more sensitive to stray light in the sky than the human eye.

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Regarding making a cross-hair EP: I turned an Antares 25mm 70 deg SWA into a finder EP first using the trick with the hairs, later by getting a cheap reticle etched on glass from the Surplus Shed and inserting it into the EP

IMAG0707.jpgIMAG0708.jpg

 

I later added a hole and inserted an illuminator. Works a treat

 

IMAG0738.jpgIMAG0740.jpg

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