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Finder scopes with exchangeable EPs

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#26 SloMoe

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Posted 28 March 2020 - 08:07 AM

Morning Elsie, I've read my way to here on this thread, usually as of late just reading posts, anyway I've found Jon's advise well worth heeding.

 

He did a mod to an Orion finder with a Carton objective that I copied and still use to this day, it's field isn't as wide as you get with a 9 X 50 but when you get used to finding things up there the widest fov in a finder isn't as important as the light gathering capabilities of aperture. 

 

Now that finder is set up with just one eyepiece that yields about 14x and that's enough, it just a finder and the scope is the main viewing instrument anyway, don't over think the finder.

 

In time you'll find yourself getting real close with the Telrad, centering with the optic finder then discovering the target with your main scope.

 

Also another thing that seems to be on everybody's mind is trying to hurry to get there, those stars have been up there a very long time, even longer than Jon has been around,,,,,,,

 

Take your time,

 

EDIT:

You mentioned that the dove tail for your scope had been installed askew making it difficult to align your finder, I think it was in the first post, anyway that should have no relevance on aligning your finder at all, the finder is aligned to the axis of the main scope, not the mount.


Edited by SloMoe, 28 March 2020 - 08:11 AM.

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#27 Jon Isaacs

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Posted 28 March 2020 - 08:41 AM

Morning Elsie, I've read my way to here on this thread, usually as of late just reading posts, anyway I've found Jon's advise well worth heeding.

 

He did a mod to an Orion finder with a Carton objective that I copied and still use to this day, it's field isn't as wide as you get with a 9 X 50 but when you get used to finding things up there the widest fov in a finder isn't as important as the light gathering capabilities of aperture. 

 

Now that finder is set up with just one eyepiece that yields about 14x and that's enough, it just a finder and the scope is the main viewing instrument anyway, don't over think the finder.

 

In time you'll find yourself getting real close with the Telrad, centering with the optic finder then discovering the target with your main scope.

 

Also another thing that seems to be on everybody's mind is trying to hurry to get there, those stars have been up there a very long time, even longer than Jon has been around,,,,,,,

 

Take your time,

 

EDIT:

You mentioned that the dove tail for your scope had been installed askew making it difficult to align your finder, I think it was in the first post, anyway that should have no relevance on aligning your finder at all, the finder is aligned to the axis of the main scope, not the mount.

 

 

Here is a link to a thread where I describe this modification:

 

https://www.cloudyni...r-meets-carton/

 

Jon


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#28 SloMoe

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Posted 28 March 2020 - 10:41 AM

Here's a thought Elise, since you're planning on AP in the future, research for a guide scope that can second as an optical finder.

 

EDIT: Only because I don't have any back ground in AP I don't know of one off hand, but it seems that would be worth looking into.


Edited by SloMoe, 28 March 2020 - 10:54 AM.


#29 Eliserpens

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Posted 28 March 2020 - 03:40 PM


 

EDIT:

You mentioned that the dove tail for your scope had been installed askew making it difficult to align your finder, I think it was in the first post, anyway that should have no relevance on aligning your finder at all, the finder is aligned to the axis of the main scope, not the mount.

Perhaps I did not explain sufficiently.  The dove tail was so far off that the finder could not be adjusted far enough to achieve alignment (I came to the end of the wormscrew).  Does that make sense?  There was one suggestion: to loosen the dovetail screws and see if there was any play in the angle.  I did that and the bracket rotated just enough that I can not align the finder and scope.  ee
 



#30 SloMoe

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Posted 28 March 2020 - 06:14 PM

Not having a photo of what we're discussing, I'm thinking you're talking about the dove tail that secures the scope to the mount,

Is there a dovetail that secures the finder to the scope?

Are you speaking of the finder shoe?


Edited by SloMoe, 28 March 2020 - 08:13 PM.


#31 SloMoe

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Posted 29 March 2020 - 07:10 AM

Ok,,,, sorry, good morning Elsie,now I get it, your finder shoe was installed askew, 

 

You might just remove one of the shoe screws, and lay a piece of double sided tape down for one side of the shoe and use the other screw to secure the shoe to the scope.

Slight tilt of the shoe won't affect how it aims but it would allow you to rotate the shoe to correct it's axis alignment.

 

Most finders don't really need both screws anyway as that they don't weigh much, or even the average 9X50 finder wouldn't need both screws.

You could trim the tape to length to clean up the appearance of it, 

 

These scopes when made have screws holding each end ring onto the tube of the scope, those screws are pretty much lined up with the axis of the tube so you can use masking tape or painters tape to stretch from one end to the other of the scope using those screws as guides for the center line you need to align the shoes or even when you get your Telrad.

The nice thing about using double sided sticky tape is that if you weren't successful with your line up you can use a hair dryer set on high to heat the tape and it peels right back off without any damage to the finish of the scope.

 

So like if you put your new Telrad on in one place and then change your mind about where you want to mount it after you've used it a few times you can move it, a roll of 3/4 wide 3M double sided tape is cheap, remove the remaining tape from the first attempt, clean off the left over adhesive with alcohol and put new tape on and try again.

 

Heck I've even built up a pad of double sided tape on a shoe to form the radius of the the OTA and used that very successfully for finders on spotting scopes, like on a sliding dew shield that couldn't have any thu fasteners on it because it slides back over the ota for storage

 

Hope this helps a bit,


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#32 Eliserpens

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Posted 29 March 2020 - 08:40 AM

Thanks SM - and yes, you do understand.  Removing one screw is definitely a possibility - but will that leave a nut rolling around in the tube?  Remember, I can't get into the tube without removing the meniscus lens - and somehow doubt that that would do much good to the collimation!

 

Is there a particular brand of double-sided tape that telescopists use?  I did think of that option - but was concerned that it would be strong enough for a 2lb finder scope (coming Monday!).

 

ee



#33 SloMoe

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Posted 29 March 2020 - 12:09 PM

Elsie, as long as you have one screw in place and secure the shoe would easily handle that load.

 

Now as far as the loose nut goes, don't let it get behind the wheel or it may crash,,,,,,,,

 

Get it?

Loose nut behind the wheel,,,,,,,,

 

Ok, enough silly, I'd get a small earth magnet, they're pretty strong, and put it down near the bottom on the side and that might trap the nut so it doesn't rattle around.

 

So when you do this work make sure your ota is horizontal so the loose fasteners don't fall towards the mirror, just down, then slowly lift the front and slide the loose fasteners down towards the magnet.

 

Even at that those fasteners are so small they just might never be an issue anyway.


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#34 Eliserpens

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Posted 29 March 2020 - 12:16 PM

I have a better plan: leave it as it is and use it for the new finder - that will have far more alignment play with traditional ring holders.  I'll save the Celestron red dot for my other scope (a 100 mm refractor on order) and use the Telrad thats on its way instead.  QED. :)

 

:)


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#35 SloMoe

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Posted 29 March 2020 - 03:38 PM

oh sure, go and get practical after all the difficult brain work I went through,,,,,,,,,,

 

That sounds like a good plan, also get a second base for the Telrad for the newer scope on order,,,,,

That is if you haven't already,,,,,


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#36 Eliserpens

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Posted 29 March 2020 - 06:25 PM

LOL!  I shouldn't need one since the Celestron finder will go on there - I have get another Star watcher bracket (I like these because the holder lifts the finder off the tube so its a little easier to look. 



#37 SloMoe

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Posted 29 March 2020 - 07:17 PM

There's a vendor in the classifieds, goes by Dr. Benway, he has a bunch of 3D'd printed finder attachments,

I know things don't cross the border well but some might help lift the finder up where it's comfortable.

 

I found that if I raised the Telrad about 2" it was very easy to use, easier on my back too, just that little bit can make a big difference.

 

Benway has a Telrad adapter that fits the Telrad base to a Synta/Vixen shoe, that's the one I use.

https://www.cloudyni...vetail-adapter/


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#38 SloMoe

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Posted 29 March 2020 - 07:28 PM

With Benways's base adapter is that you save space on your scope in tha the Telrad base takes up some space, plus you can move the Telrad way forward which really helps,

 

I have a few other finders but these are my favorite, can be switched around to any shoe,,,,,,

 

Normally I just star hop with the laser till I find it in the optic finder, I use the Telrad more at outreach events, it's real easy to aim the scope or keep the target in the scopes fov.

Then it's where the laser is in the pic.

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Edited by SloMoe, 29 March 2020 - 08:06 PM.

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#39 Jon Isaacs

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Posted 30 March 2020 - 12:14 AM

Elsie, as long as you have one screw in place and secure the shoe would easily handle that load.

 

 

The scope in question is a 190mm Mak-Newt.  There's not much radius on the tube and the material is not particularly thick so it really does take both bolts to hold the dovetail in place.  And being a closed tube design, removing a bolt means there's a nut loose inside the tube with no easy way to remove it. 

 

If it were really necessary to get at the nuts, I would remove the primary mirror (mark it's position) and reach down the tube rather than removing the corrector.

 

Jon


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#40 SloMoe

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Posted 30 March 2020 - 07:12 AM

Don't fret Jon, she's not going to loosen anything, geeese, read her post.

 

Elsie, the scope you have coming is also a Newt, right?

 

Time for some lessons in collimation.


Edited by SloMoe, 30 March 2020 - 07:18 AM.

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#41 Jon Isaacs

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Posted 30 March 2020 - 07:50 AM

Don't fret Jon, she's not going to loosen anything, geeese, read her post.

 

 

I did read her post.  But it's not just us three that are following this thread and there maybe others in the future.  

 

Jon


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#42 Jeff Lee

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Posted 30 March 2020 - 08:02 AM

I recently added Starsense for SkyWatcher and had to lose my 8 x 50 finderscope. However, I do have an AT60mm guide scope and with a Ultimta 30mm EP (cannot use a diagonal and come to focus) it mounts on my camera bracket so not only is my guide scope now permanently attach to the C8 it acts as a finder. Actually it is a great finder and since Starsense really only needs a finder for the first alignment not really needed. However, when I am using AZ it can still be useful as a widefield view similar to a ST80 with the ZWO224 (You can run two SharpCap sessions). Always good to get more use out of stuff.


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#43 cl300stick

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Posted 30 March 2020 - 09:35 AM

I just got this off of AM. Amazing finder and near APO quality glass. It's a Stellar View 10x60. Will mount right up and weighs in under a pound. The focus is amazing and you can switch out eyepieces at will.

 

sv60.jpg

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#44 Eliserpens

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Posted 30 March 2020 - 02:17 PM

 cl300 - my Stellarvue (also with exchangeable EPs) is scheduled to arrive this afternoon (in the next hour)!  But I opted for the 9x50 (F050W2) so lets compare notes.

ee


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#45 Eliserpens

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Posted 31 March 2020 - 09:45 AM

The Stellarvue 9X50 arrived safe and sound together with the mounting rings on the 'universal' dovetail.  It looks really terrific, beautifully made and could be used as a bird spotting scope (maybe they sell them in that market too?).  I did not get the graticule illuminator  - but the port is in the EP so its easy to add if needed. 

 

The EP has a focusing ring for the graticule and a second ring below it focuses the scope - no groping to the objective. 

 

The 'universal dovetail' is basically the same, or slightly narrower wedge, than for vixen/star-watcher but lacks the end stop, which is really no problem.  Now I have to figure out how to use the mounting rings (new to me).  Seems that alignment may be a bit of a tedious procedure as you obviously have to loosen one side when you tighten the other.  Perhaps there is a short-cut for this. 

 

So far so good - and we are supposed to have some clear skies starting tomorrow morning! 

 

[Still waiting on the Telrad; unfortunately, I can not mount both the ARCI and the Celestron finder as both use the same mount.  And I have no double sided tape....]


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#46 Eliserpens

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Posted 31 March 2020 - 09:49 AM


Elsie, the scope you have coming is also a Newt, right?

 

Time for some lessons in collimation.

Nope, the new scope is my grab-and-go refractor; Astro-Tech AT102ED 4" f/7. 



#47 SloMoe

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Posted 31 March 2020 - 08:55 PM

No tape, well that's a problem,,,,,,,,,,

 

Not sure what to suggest as that I'll get shot down, 

 

The 102 only has one shoe, an extra base for the Telrad if you want to use it for both scopes,

 

For my terrestrial viewing I use a C90, on my EQ mount set to alt/az that way I can use the slo motion adjustment knobs

 

Your new finder could easily work as a bird scope, check the dove tail for a 1/4 in hole thats threaded, if none is there easy enough to drill & tap a hole for a camera tripod mount.


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#48 Eliserpens

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Posted 31 March 2020 - 09:23 PM

Great ideas - though I'd rather use my 7x50 binoculars for the birds :) 

 

I want a reasonably light-weight az mount for the refractor.  I'll find tape somewhere - maybe order it (I'm in hiding from the covid-monster), worth the postage!  



#49 SloMoe

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Posted 01 April 2020 - 07:16 AM

Stay hidden!

 

I ended up finding an old Mead EQ mount on CL, had to completely disassemble it. clean & lube up everything as I re-assembled it, then instead if putting the clam shell back on I installed a dove tail clamp.

 

Then on the C90, because it came with a mount that was not dove tailed, just a pad with 1/4" hole in it for a camera type tripod, I removed that and installed a short dove tail on the ota with pop rivets,,,,,,,

Just like the factory did with the original camera pad, but I also added washers inside to reinforce the grip of them, I removed the corrector plate to access the inside of the OTA, nothing to it, no harder than removing the other end.

 

Thing with the C90, with all the light available during the day I can magnify up to 450X with detail, so if the bird still has crumbs on it's belly left over from breakfast I can tell you what it had to eat,,,,

 

Still waiting for a Nagler T6 2.5 to pop up in the classifieds, missed a few of them while I was on break from this place, no big deal I Barlow my Nagler T6 5 but still I think I'd like to get one.

 

Geese, sorry Elsie, started to ramble, it's an old man thing,,,,,

 

Just thought of something, with the 102 being a tight radius the base of the Telrad may not seat itself well, they're designed for larger OTA's, 

The Benway adapter may be a good option but then you'd have to install another shoe,,,,,

 

You know what I would do is to install a shoe up on the dew shield of that scope, it will move the Telrad way forward like a cannon sight, actually a very nice place for it to be, a bit bulky looking but not heavy by any means.

 

I used the Baader Sky Surfer red dot on my brothers refractor that way, he loves it there, and it's probably going to replace my Telrad on my other scopes because it just looks like it should be there and not a like a brick with a window on top, never did like that about the Telrads.

The Sky Surfer finder has a bunch of mount options for different finder shoes, unlike the Telrad which has only one, the one for the Synta/Vixen shoe is very robust so I mounted a SV shoe on his dew shield with double sided sticky tape like I described on one of my earlier replies on this thread, and that little bugger ain't movin' round a bit.

 

But since designing and building my cell phone bracket for my scopes I haven't used the Telrad.

It's very successful finder option, these guys say it doesn't work but then again these guys failed at their attempts to  design & build one so I guess because they can't do it no one else can, 

 

There I go again, rambling on,,,,,,

 

Go luck on your ventures Elsie, I've got to go back and work now and won't be back for a while.


Edited by SloMoe, 01 April 2020 - 07:31 AM.


#50 Eliserpens

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Posted 01 April 2020 - 09:08 AM

Fun stuff - love the way everyone is so handy here.  In time I'll get into it too [used to build much of my own gear in the lab].

 

"You know what I would do is to install a shoe up on the dew shield of that scope, it will move the Telrad way forward like a cannon sight, actually a very nice place for it to be, a bit bulky looking but not heavy by any means."  I wondered if that was possible,  I guess it depends on whether the dew shield is built in or an add-on (as I'll need for the MN190). 

 

But its all pie in the sky (hehe) until the scope comes and since its made in china that could be months.

Thanks for all the encouragement :)

 

ee




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