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Finderscope solution - help wanted

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#1 therealdmt

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Posted 04 October 2020 - 01:11 AM

Hey, all.

 

What’s your preferred solution for visually pointing your telescope within an approximately constellation-sized view of the sky:

 

a) wide angle finderscope (if such exists)
b) red dot finder
c) Telrad
d) mounted green laser pointer
c) other

 

 

I briefly experimented with the ‘alt-az coordinates w/ digital inclinometer’ method with some success back in August and I guess I’ll get back to that, but there’s some frustration with looking up in the night sky [naked eye] and seeing right where a DSO should be, but not really understanding if my telescope is actually pointed in the right area with only the view in my 8x50 finderscope to go by.

 

 

While we’re at it, it seems to me from various comments I’ve come across that red dot finders are somewhat loathed, at least by some people. I’ve never used one myself, so what’s the issue(s)?

 

In contrast, it seems Telrads are widely well-regarded, but they look huge to me and I’m not sure how I’d mount one on my Sky-Watcher 100 ED refractor.

 

Meanwhile, a green laser pointer could be cool for at home use, but from the one semi-dark sky site I know (the only place I’ve taken a scope to so far besides my porch and front lawn), people are often there trying to take long exposure photos of the Milky Way, so using a laser there would be pretty unfriendly (read: hostile) to the other night sky aficionados.

 

The method I ened up using to find my first two non-Pleiades DSOs last weekend (the Double Cluster and M31) was to find them first in my binoculars, thereby narrowing down the search area enough for my finderscope. This however didn’t work for me for finding Uranus though as there were no sufficiently prominent stars nearby (I think I saw Uranus in the binocs but never did find the same target in my finderscope), nor did it work for Neptune, which as far as I could tell wasn’t visible in my little binoculars (nor was there anything prominent enough near where Neptune should have been for me to focus in on and star hop from there). Likewise, the "binoculars first" method wouldn’t work well for DSOs too dim/small for my binoculars. I mean, like I could see naked eye where some things should be in relation to main stars in Cassiopeia, but in my finderscope I couldn’t be sure which star of Cassiopeia I had in view! I could probably get better with practice, but it would be so much easier if I could just see the whole of Cassiopeia, or at least most of it.

 

Your suggestions and experiences will be appreciated.

 

- David


Edited by therealdmt, 04 October 2020 - 02:24 AM.


#2 B 26354

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Posted 04 October 2020 - 02:13 AM

I'll add "None of the above" to your list.

 

For targets that aren't naked-eye visible, knowing the sky well enough to know where your target is, is crucial. Once you've acquired that skill, it's simply a matter of learning how to point the scope at the chosen spot, by looking down the length of the OTA. All it takes is practice, practice... and more practice. The good thing is... you can practice on bright targets at night (bright stars, the planets, the Moon...)... but you can also practice during the daytime, on anything you can see. After 6.5+ decades of doing this. I can effortlessly point any of my scopes to within about 1.5-degrees of my target... which is well within the FOV of my finder-scopes.


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#3 clearwaterdave

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Posted 04 October 2020 - 02:14 AM

Hi David.,For me it wasn't the finderscope that was the problem.,it was knowing right where to look.,This may seem easy enough with a chart right in hand but if the target isn't big flashy eye candy and you don't see it right away.,then you end up scanning around and soon are way off target.,

  For me the solution was learning to really read the chart or app.,and knowing the fov of my finder and ep.,Reading the chart means memorizing what the stars in the fov will look like when the target is centered.,and being able to measure distances on the charts and in the sky.,With charts with fewer stars knowing/judging the distance is very important because you don't have the fov stars to use.,

  As for finders.,I use lasers and raci 8x50.,The laser puts me on my nakedeye star or shows me where I am pointing or where I know something is.,the 8x50 is used to hop to the target area and the ep fov gets me on it.,

  This does take practice.,I have to look at the fov nest a few times still because I forget to really look at it.,.lol.,.

  Learning to starhop has gotten me better at reading charts and at finding stuff,.I have used push-to but now I would rather hop.,and I have lots of stars to hop with.,good luck.,

  practice.,and a good chart/app and it gets easier.,cheers


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#4 markb

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Posted 04 October 2020 - 02:20 AM

I like momentary cord switch GLPs, but the cold weather and star party issues have me using a 36 to 40mm window green/red dot specifically made for large caliber firearms.

 

You can directly mount (machine screws into threaded holes or nut and bolts) a Picatinny rail to let you mount it to the tube, or a telescope finder shoe adapter to Picatinny / Weaver rail. I have Vixen/Synta type finder shoes on most of my scopes so I use stalk adapters.

 

I like the two eye viewing and the micro adjusters needed on firearms. I have no issues on scope aiming with short fl eps since aim adjustments are so precise. Optical finders always seemed to need fussy readjusting.

 

These are not the types sold for scopes, and I am growing to like them more on each use. The little telescope ones were awful bb gun adaptations, except the TV version.

 

Some have significant silvering for daytime use, and I have removed it with polish, but my next will be a chemical removal (likely ferric chloride circuit board etchant).

 

Get the thin rim, large exposed window type for best two eye viewing. I use one of the red projections, but green works well for daytime testing or collimation work on an artificial star and Duncan mask.

 

Telrads are great but huge, and the much smaller Rigel finder, same principle, is a really nice alternative. Good alternative.

 

But I've had Rigels break or crack due to the plastic construction if they get whacked.

 

I have a box of optical finders to sell, they just don't suit me at all.

 

As to aiming without anything, I can't get the knack on a big scope, regardless of familiarity with the area of the sky.

 

It's hard to beat getting even a planet at 120x in the FOV first time, almost everytime with a Rigel, GLP, or firearms grade projected dot.


Edited by markb, 04 October 2020 - 02:29 AM.

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#5 therealdmt

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Posted 04 October 2020 - 02:20 AM

I'll add "None of the above" to your list.

 

For targets that aren't naked-eye visible, knowing the sky well enough to know where your target is, is crucial. Once you've acquired that skill, it's simply a matter of learning how to point the scope at the chosen spot, by looking down the length of the OTA. All it takes is practice, practice... and more practice. The good thing is... you can practice on bright targets at night (bright stars, the planets, the Moon...)... but you can also practice during the daytime, on anything you can see. After 6.5+ decades of doing this. I can effortlessly point any of my scopes to within about 1.5-degrees of my target... which is well within the FOV of my finder-scopes.

Okay, I can see that.

 

Fortunately, I know the night sky pretty well already from decades of sky watching. And I started out this summer with a little Galileoscope which I couldn’t point worth crap at first, but then, like you said, after a couple of intensive daytime sessions practicing on terrestrial targets, I got much better with. Still never got as accurate as I’m wanting now with the "real" scope, but like you said, maybe some concentrated practice and time/experience is what’s needed. I’ve only used the scope, day and night, 4 times total so far (the first day setting it up, and then 3 nights astronomical viewing)


Edited by therealdmt, 04 October 2020 - 02:30 AM.

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#6 sg6

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Posted 04 October 2020 - 02:22 AM

a) wide angle finderscope (if such exists)
b) red dot finder
c) Telrad
d) mounted green laser pointer
c) other

 

While we’re at it, it seems to me from various comments I’ve come across that red dot finders are somewhat loathed, at least by some people. I’ve never used one myself, so what’s the issue(s)?

 

In contrast, it seems Telrads are widely well-regarded, but they look huge to me and I’m not sure how I’d mount one on my Sky-Watcher 100 ED refractor.

Wide angle finders are common, mainly they are usually what are supplied. The straight through types usually don't go well on a dobsonian mounted newtonian as you have to lie your head along the OTA, people change over to right angle ones.

 

I like red dots, use them on refractors and SCT/Maks.

Cannot use a Telrad, just never see the targetting images, so far never had any success.

GLP, used often when a scope we had sort of gave up going to the targets - pointer on scope manually slew scope.

 

Red dots and I suppose Telrads sort of operate odd. People look AT the finder. With a red dot you have to ignore the finder and look past/through it at the sky. Then the optics of the finder produce the red dot. The dot is created as if at infinity so you have to look at infinity to see it - people look at the finder 12-24 inches away not infinity.

 

For me I would use a red dot and a pointer - likely a modified rifle sight as they mount properly and are easier to adjust.

 

"Other" - have used the tips of the scope rings to get Jupiter and Saturn. Maybe unfortunate but it worked annoyingly well.

 

Think there are around 5 types of finders. You have to find the one that works for you. And people will say "This one" because that is the one that works for them.


Edited by sg6, 04 October 2020 - 02:36 AM.

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#7 Redbetter

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Posted 04 October 2020 - 02:38 AM

 

While we’re at it, it seems to me from various comments I’ve come across that red dot finders are somewhat loathed, at least by some people. I’ve never used one myself, so what’s the issue(s)?

 

In contrast, it seems Telrads are widely well-regarded, but they look huge to me and I’m not sure how I’d mount one on my Sky-Watcher 100 ED refractor.

 

Meanwhile, a green laser pointer could be cool for at home use, but from the one semi-dark sky site I know (the only place I’ve taken a scope to so far besides my porch and front lawn), people are often there trying to take long exposure photos of the Milky Way, so using a laser there would be pretty unfriendly (read: hostile) to the other night sky aficionados.

Beats me why some loathe RDF's.  RDF's are imperfect, but are by far the least expensive and most flexible to mount, especially since the typical Celestron RDF comes with various mounting feet.  RDF's are all I use on refractors, and even on the 127 f/15 Mak.   I have an 8x50 finder that came with my 110ED, but I don't really use it.  Instead I have a simple Celestron RDF mounted forward on the rings (my rings have some off-axis mounting points.)  I could use the now empty finder shoe on the focuser, but I like having the RDF mounted further up where it is easier to sight (* see below.)

 

There are perhaps two primary complaints about RDF's: 

  1. Depending on the mounting position used they can require some awkward positioning to sight down.  (*see my example above how I work around that on one scope with a longer tube.) 
  2. The other issue is that sometimes they just don't want to work.  I have several of them, and the potentiometer switches on some can be finicky, especially in cold weather.  I can typically work around this by squeezing the sides of the housing, cycling off and on, or flicking the finder with my finger  Once or twice I have had to remove the battery housing cap, reseat, and reattach.  I keep a spare so that I can just swap if one is not being cooperative.  So far I have none that are actually dead long term.  Another that I thought was dead I had replaced under warranty (they don't ask for return, they just send the cheap ones to you.)

Some minor concerns are:

  • Sometimes a particular RDF won't have enough adjustment range for how it mounts on the scope.  When this happens one can request a warranty replacement for the defect, and/or shim the finder in some fashion to position its axis withing the adjustment range.  I had a slightly different Meade version of one of these finders that had stiff/very little adjustment that was insufficient, they sent me a new one.  Meanwhile, I found a scope that the problem child finder fit better on within its adjustment range.
  • The dot can be too bright for some even on the lowest setting.  I don't see this as much of a problem, as I don't have trouble getting close enough while following with the other eye open.  
  • There is some parallax.  Again, I have not found this to be a problem with the RDF's as I don't have trouble positioning my head/eye adequately or with finding the target in the scope's eyepiece.

Telrads are nice for larger scopes and I have two.  Yep, they are far bulkier than they need to be, which is why I don't use them on refractors. 

 

For refractors, which allow some respectable field of view, I prefer to use some sort of wide true field eyepiece for the actual star hopping.  My ED refractors are set up for 2" eyepieces so it isn't hard to get a wide field.  However, I even converted a 900mm f/11 to 2" focuser which allows me to achieve 2.9 degrees of field for finding if I want/need.  

 

My general recommendation is to use RA or RACI finders with an RDF or Telrad/Rigelfinder.  The main exception is if the scope has enough field of view that you don't feel there is a need for a magnifying finder...which is the way I have operated with refractors.   I didn't want to clunk up my ES 127 f/15 Mak with a magnifying finder, but the narrow field of view was problematic for star hopping in the suburbs, so I put a 2" diagonal on it and it works decently now.

 

I am not a fan of GLP's.  I have one that I won as a prize, the cat's love it.  I wouldn't consider using it in the backyard as we have far too much air traffic since I am close to an airport.  At dark sites I don't care for them.


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#8 therealdmt

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Posted 04 October 2020 - 04:55 AM

Okay, I’ve learned a lot already. I was just watching a YouTube video on using a finderscope where the guy said to view through the finderscope using both eyes (one through the finder, the other taking in the sky for context, and this makes a lot of sense to me. Perhaps unfortunately, I "upgraded" the finder on my telescope package to one with a diagonal, so I can’t do that lol.gif  Well, I might go back and get the straight-through viewing one, too.

 

Beyond that, I think I’m gonna give a red dot finder a shot and view through it like sg6 says whilst keeping focus on the background sky and see if that works, then hone in on my intended target using the 8x magnifying finderscope from there if needed as Redbetter says. Also per Redbetter’s info, if that works out, I’ll pick up a 2nd rdf as a spare, since they sound a bit fragile/finicky. 
 

If the rdf doesn’t work out, I’ll order up one of those Rigels that markb mentioned.

 

Finally, as clearwaterdave suggests, I should work on getting more familiar with the star charts for my intended targets. The app I’m using is actually for visual sky watching and only goes down to magnitude 6.5, and beyond that it has a simple toggle on/off setting to display "All DSOs". I should step up to a dedicated telescopic viewing app like Stellarium and figure out more exactly what my finder should show before a session. Admittedly, I’m kinda just going out there and trying to find whatever comes to mind. But, I’m familiar with the constellations and also familiar with where a few famous DSOs should be in their constellations, so it’s tempting to just wing it like that. Works for binoculars, but maybe my telescope sessions will require a little more planning.

 

Finally, finally, I might order an eyepiece that will let me achieve my scope’s maximum TFOV of 2.93°. Gonna get one that gives me around 2.3° first though, so that might help in the meantime (still quite a bit less TFOV view than a finderscope though, I’d think)


Edited by therealdmt, 04 October 2020 - 05:12 AM.


#9 MellonLake

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Posted 04 October 2020 - 07:25 AM

Finally, finally, I might order an eyepiece that will let me achieve my scope’s maximum TFOV of 2.93°. Gonna get one that gives me around 2.3° first though, so that might help in the meantime (still quite a bit less TFOV view than a finderscope though, I’d think)

If your telescope is a fast telescope (i.e f/6 or lower) I would get a 30mm APM UFF eyepiece.  Fast telescopes need better corrected eyepieces like the APM UFF 30mm.  I tried a cheap 32mm 2" eyepiece in both my 120ST and 10" Dob and the views were not good and the distortion of the field of view made it difficult to find objects using the telescope as the view finder (it looked like a science fiction space ship going to warp when panning).  The 30mm APM UFF is, in my opinion, a lifetime eyepiece, it is also lighter than and far lest costly than its competitors (31mm Nagler, 35mm Panoptic, 30mm Explore Scientific 82°).  It may be more than you want to spend but the difference compared to a cheap 2" wide angle eyepieces is pretty significant.  If you can't afford this eyepiece, I would recommend the Explore Scientific 24mm 68° as it would be very good as well (but a narrower field of view).  

 

For finders, personally, I like the Telrad/Rigel for my Dob, the target shape allows me to judge distance from stars (I found the Telrad more beneficial than the red dot finder).   Now that I am better at finding things, the green laser pointer is my goto (when well away from airports and planes).  I will also say that the right angle finder also helps a lot here and there.  Most bright DSOs can be identified in the right angle finder to then get them centred in the eyepiece (Yes my Dob has 3 finders).  On my 120ST I just use a laser pointer or red dot finder (I don't like the red dot as much but the do work fine).  


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#10 SloMoe

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Posted 04 October 2020 - 07:55 AM

I ask the guy next to me where it is


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#11 spaceoddity

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Posted 04 October 2020 - 07:57 AM

I prefer the rigel quickfinder for my refractor and smaller scopes, with a low power wide angle eyepiece. I don't use magnifying finder and find them to be unnecessary weight. My XT10i is the only scope that has a magnifying finder. It came with a 9X50 RACI plus I added a rigel qf. The 9X50 RACI can be useful in locating brighter DSO's. I don't star hop in the conventional sense. I use a triangulation method with the 2 brightest stars nearest the object I'm looking for. It works pretty well for most objects but can take some scanning for objects that aren't near any bright stars.


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#12 Jon Isaacs

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Posted 04 October 2020 - 08:21 AM

I'll add "None of the above" to your list.

 

For targets that aren't naked-eye visible, knowing the sky well enough to know where your target is, is crucial. Once you've acquired that skill, it's simply a matter of learning how to point the scope at the chosen spot, by looking down the length of the OTA. All it takes is practice, practice... and more practice. The good thing is... you can practice on bright targets at night (bright stars, the planets, the Moon...)... but you can also practice during the daytime, on anything you can see. After 6.5+ decades of doing this. I can effortlessly point any of my scopes to within about 1.5-degrees of my target... which is well within the FOV of my finder-scopes.

 

scratchhead2.gif

 

You're still using finder scopes. And I see no reason not to use a Telrad or red dot, they're more accurate than sighting down the tube.

 

Myself, with refractors, I generally use a wide field eyepiece in the main scope and then just "shoot from the hip." 

 

I just look up at the sky, knowing where the object is and just aim the scope from my normal seated position. No need to scrunch down to sight down the tube or peer through a finder. I'm pretty good at it but it does take practice. I do not recommend it for beginners as it does require knowing the sky as well as what I'm expecting to see. If I miss, I know what to do.

 

In any event, my preferred tools for finding new and/or difficult objects are a Telrad, a 50 mm RACI finder and Sky Safari Plus or Pro.

 

Sky Safari provides me with a chart that exact for my location and the current sky. I can customize it so it represents what I'm seeing naked eye, I can zoom for the finder view and further zoom for the main scope.

 

If I want to find a new object, I work between SS Pro and naked eye, identifying the region of the sky, what I can see naked eye. I then look at the SS and devise a star hop from a naked eye star to the object.  I'll often use binos at this stage to verify whatll be visible in the RACI finder.

 

This will probably be mostly the RACI finder, identifying star patterns shown in SS and moving toward the target.

 

This takes practice. It's probably best to start with star hops created by someone else.

 

The target will almost never be visible in the finder, I'm looking for objects that are not so easy. So part of devising a star hop is to identify the region where the object is, a nearby star or asterism that I can use to point the scope very close to the object. 

 

The final step is moving to the main scope. Hopefully the object will be visible in the low power eyepiece I'm using but it may be too faint to see so some more star hopping in main scope may be required. 

 

For someone starting out, the object will probably be visible in the finder. 

 

I've not had good luck with the plastic red dot finders. Most often, the alignment range is skewed enough they just cannot be aligned. And this with Refractors that other finders can be swapped back and forth without needing realignment.

 

For my 120 mm F/7.5, it has the same 900 mm focal length as the initial poster. I use a 50 mm  GSO RACI finder and shoot from the hip for initial pointing.

 

For me, it's working between. Sky Safari, the Telrad, the 50 mm RACI finder and main scope, interactively.

 

6178679-Finding M71.jpg
 
Jon

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#13 Eddgie

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Posted 04 October 2020 - 08:23 AM

There is an alternative to the Telrad called the Rigel.  While I prefer the Telrad, the Rigel has some advantages.  First, it is a bit more compact, and second, it has a nice feature where you can cause the reticle to flash on and off, making it easier to see the star positions.   It also places the viewing window a bit higher than the Telrad but it is smaller and harder to acquire the reticle.

 

The reason these finders work so well is that using a program like Sky Safari, (which has a pre-programmed Telrad cirlce in the setting) and the know size rings shown in the display, it is very easy to accurately determine the angle and distance from a known star to your subject.  Finding thinks like the Ring Nebula or Double Double is quite easy using these devices as long as you have a good app to guide you.

 

https://www.astronom...eye-finder.html

 

The reason traditional finders don't seem to work as well for me is that even aiming the finder itself can be hard.  Best to supplement the finder with a red dot device so that it is easy to aim the finder. 

 

Telrad and Rigel are dead easy to aim. Many prefer the Rigel and off of the base, the Rigel is much easier to transport, and is lighter than the Telrad. 

 

 

RACI Finders can work well though, but I don't think they are as fast as Telrad or Rigel.


Edited by Eddgie, 04 October 2020 - 08:37 AM.

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#14 desertstars

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Posted 04 October 2020 - 08:32 AM

I've always found dual use of a Telrad or Rigel QuikFinder (I use the former on the Three-legged Newt, and the latter on my two smaller refractors) and a 9x50 finder scope the best approach. This has remained true even though the 8" reflector is now on a goto mount. I still use the finders during the alignment process. Even with the right angle version of the 9x50, there are times when it's just easier to sight the alignment star through the Telrad. The resulting alignments have been good enough for my purposes.


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#15 MaknMe

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Posted 04 October 2020 - 09:31 AM

I love my Telrad. But, I still also use a 8x50 straight though finder. It helps when objects are faint or invisible to the naked eye. I like to keep my 12mm or 8.8mm eyepiece in. At 160+ X, centering the object in the Telrad ensures it is in my eyepiece.
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#16 Jon Isaacs

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Posted 04 October 2020 - 09:34 AM

 

RACI Finders can work well though, but I don't think they are as fast as Telrad or Rigel.

 

I think one needs both.  Telrads etc are effective under dark skies but of limited use under urban skies.  Telrads etc are almost a necessity for initially point a scope with an RACI finder.

 

Jon


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#17 LIVE LONG

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Posted 04 October 2020 - 10:25 AM

   On my 10" Dob, I use a Telrad & 8x50mm RACI. They work perfectly together. I cannot imagine using a finder scope, on it's own. Way too frustrating!!!


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#18 B 26354

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Posted 04 October 2020 - 11:31 AM

scratchhead2.gif

 

You're still using finder scopes. And I see no reason not to use a Telrad or red dot, they're more accurate than sighting down the tube.

 

I think one needs both.  Telrads etc are effective under dark skies but of limited use under urban skies.  Telrads etc are almost a necessity for initially point a scope with an RACI finder.

Yes, I am "still using finder-scopes"... but the OP's question was "What’s your preferred solution for visually pointing your telescope within an approximately constellation-sized view of the sky?"

 

As such, my answer of initially sighting down the tube was completely appropriate. No cause for confusion or head-scratching.

 

And while use of a red-dot or a Telrad may be "more accurate" for you... my method of getting my scopes pointed at my target to within the FOV of my finders (currently, one straight-through and one RACI) has been been accurate enough for me for sixty-six years... so adding a red-dot or a Telrad to the mix has simply never been necessary.

 

I did try using a red-dot on a Picatinny-rail/hot-shoe mount for my camera/lens combinations... but I just didn't like it. Gave it to someone here on C-Nights.

 

As with everything else in this wacky astro-pastime business... it all comes down to what works best for the individual.  biggrin.png


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#19 Sketcher

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Posted 04 October 2020 - 11:48 AM

Having skimmed through the above -- reading most of it -- what struck me was that different people have found different finders and/or methods that they've found to be most effective for them, while using their telescopes, from their sky conditions.

 

The obvious take away for me is that there is no one solution that's going to be best for everyone.

 

So I'll try a different approach:

 

When I started out, my first telescope had no finder; but I really, really wanted to observe all that I could possibly observe.  Fortunately for me, that first telescope was a long-tubed refractor; and that simplified sighting along the OTA (optical tube assembly).  After much practice, that ended up being good enough; but it was never easy, especially for observing deep-sky objects that were invisible to the naked eye.  Yet, I did manage to find M13, M31, M81, M82, M57 and other "goodies" with that first 65mm refractor.

 

Later, being older, and having some experience (and knowledge) behind me, and with a different telescope that came with a straight-through magnifying finder; the whole "learn by doing" routine began all over again.  More practice, practice, practice; and as before, what I had was proven to be "good enough".  At this point in my hobby I wasn't aware of there being other finder choices.  There was no Internet.  There was no one to ask.  I had what I had and I knew what I wanted to accomplish -- so I found ways of making it work -- for me.

 

OK, so those were not "easy" times.  Times have changed.  There are more options that more of us know about -- and there are forums like CN where one can ask for assistance, different opinions, different preferences, etc.

 

Still though, our opinions and our favored methods differ widely depending on the person, their telescopes and sky conditions.

 

Jon, above, suggested (in his opinion) that one needs (or would benefit from) having both, an RACI finder and a Telrad (or other 1x finder).  Well, I would agree when I'm using one of my larger reflecting telescopes -- I find it worth the expense and effort to have one of each on my larger Newtonian reflectors.

 

But my preference is different when it comes to my refractors.  The built-in open sight on my Galileoscope is all that's needed (for me) on that telescope.  A single, red-dot finder is all that's needed (for me) on my ST-80 refractor.  And, moving to my larger refractors, I prefer using only a single 8 or 9x50 RACI finder.   So, one person, under consistent sky conditions has developed different finder preferences for different telescopes.

 

Yet another part of all of this is (of course) one's sky conditions and some of the other stuff one might make use of -- for me, that would include whatever atlases (I have many to choose from) if any, that I choose to take out with me.

 

And last but not least is one's knowledge -- knowledge of the night sky, the constellations, etc. and knowledge about one's equipment -- knowing the true fields of view (along with celestial directions in the various fields of view) of all my finders and of all my eyepiece + telescope combinations.  All of that can and often does make a difference as well.

 

So now, I have a wide variety of options when it comes to finding things in the night sky.  So how am I to offer advise?  My skies are different from those of the OP.  My telescopes are different.  My other tools (such as star charts are different.  My knowledge is different.  The skills I've developed are different.

 

My bottom line here:

 

There are many feasible options available.  Choose one (and it really shouldn't matter all that much which one you choose) and work on developing the skills needed to make that choice work -- for you, under your sky conditions, etc.  There is no one way that will be preferable for everyone -- certainly not with every telescope under all sky conditions for all observers regardless of their knowledge and experience.

 

In the end, it's about learning how to find "stuff" with whatever you have to work with.

 

Charles Messier didn't have access to RACI finders.  There were no Telrads,  There were no GLPs.  There were no red-dot finders.  Yet, he was able to determine where any objects he came across were located on the celestial sphere with enough accuracy for his purposes.  In short, he learned enough and developed his skills well enough to be able to use what he had to accomplish what he needed to accomplish.

 

In the end, it's less about the equipment and more about the individual, their knowledge, and their skills.  But this is CloudyNights.  So all that's important (or so it often appears) is the equipment.

 

After all is said and done, the equipment doesn't matter.


Edited by Sketcher, 04 October 2020 - 12:23 PM.

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#20 barbarosa

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Posted 04 October 2020 - 12:04 PM

Yet another one of the great divides in this hobby. So I will reprise my own journey and let you draw your conclusions.

 

I live in a suburb, very close to the big ciy. There are other and larger suburbs a few miles to the north and east. Some one has absquatulated with the Milky Way and other target formerly visible here. My night vision has not improved with age.

 

6x30 finder, Telrad, red dot, green laser (borrowed and returned but they do work), 8x50 finder, a very nice SV SV-50 finder, and currently 6x30 or oem 8x50 depending upon the scope. That 6x30 probably gets the most use when sighting down the tube won't do. Oh and I have a Televue Starbeam that has never been used. Beautiful bit of gear, I should sell it, because I will never use it.

 

What then is the best overall finder in my opinion, the $15 red dot or the $240 Starbeam? The answer is a go to mount and a red dot or a cheap 6x30.

 

For me the pleasure is in the seeing not the finding.


Edited by barbarosa, 04 October 2020 - 12:05 PM.

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#21 John Fitzgerald

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Posted 04 October 2020 - 12:15 PM

There is another ongoing thread on the nearly the same subject here:

 

https://www.cloudyni...ed-dot-finders/



#22 John Fitzgerald

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Posted 04 October 2020 - 12:18 PM

 

 

In the end, it's less about the equipment and more about the individual, their knowledge, and their skills.  But this is CloudyNights.  So all that's important (or so it often appears) is the equipment.

 

After all is said and done, the equipment doesn't matter.

Sketcher,

So very true, IMO also.  Knowledge does matter the most.   So, study your star maps in your down time.  Learn on the sky how much a degree is.  Learn many degrees your fist subtends at arms length.  You will soon be able to get things into a 5 degree binocular or finderscope field by dead reckoning from known naked eye points.


Edited by John Fitzgerald, 04 October 2020 - 12:23 PM.

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#23 Paul Sweeney

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Posted 04 October 2020 - 01:09 PM

All of the different finders have their strengths. Which one is "best" is very individual. So my suggestions are more general.

Most targets are not visible to the naked eye nor in 1x finders, and many will not be visible in a 50mm finder. So you have to learn the sky. Star hopping is a necessity, and you will really learn the sky. You need to learn to translate what you see in an atlas into what you see through the finder or eyepiece. No matter what finder you use, you will almost always need to home in on your target (that you can't see in the finder) based on the star field. This takes practice. Don't get frustrated.

Read books thst include tours in them. From them you can learn some tips and tricks on how to locate objects. These books literally walk you through a star hop to a target.

Straight through sighting devices are good at low elevations, but how do you aim at the zenith? Here it gets tough, and depends a lot on your scope and your ability/willingness to bend your body into a pretzel to get at the finder. Here the 90° correct image finder seems like the solution, but even with these you need to be close to the target to see it in the finder. Here I find using setting circles a good way to get close to the target. Then I can close in on it with the finder.

Learning to aim along the tube is a handy skill to learn. I do it in two steps. First, look down the tube from the top, like aiming a rifle. That gives the azimuth. Now look along the tube from the side to get the elevation. With some practice this will get you very close to your target.

A GoTo mount solves a lot of problems, and brings a bunch of new ones with it. I am 63 and have been doing astronomy since I was 10. I bought my first GoTo mount last week. Works great, especially near the zenith.

Is there a club in your area? If yes, contact them. I will be very helpful to look at and through the various finders, so you can determine what works for you. You will also get first hand experience and you can avoid buying finders thst you don't want.
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#24 MellonLake

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Posted 04 October 2020 - 01:36 PM

A GoTo mount solves a lot of problems, and brings a bunch of new ones with it. I am 63 and have been doing astronomy since I was 10. I bought my first GoTo mount last week. Works great, especially near the zenith.
 

Too true....manually finding things near the zenith is hard in any mount mount system I have used (EQ, AZ, Dob).  The green laser pointer finder is by far easiest to use when hunting for objects near the zenith. 


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#25 Tony Flanders

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Posted 04 October 2020 - 01:40 PM

I briefly experimented with the ‘alt-az coordinates w/ digital inclinometer’ method with some success back in August and I guess I’ll get back to that, but there’s some frustration with looking up in the night sky [naked eye] and seeing right where a DSO should be, but not really understanding if my telescope is actually pointed in the right area with only the view in my 8x50 finderscope to go by.


For that particular purpose, the ideal tools are either a red-dot finder, a red-circle finder, or a laser-pointer finder. They are all more or less equivalent, though the circles of red-circle finders have additional uses above and beyond the purpose you're describing above.

Sighting down the tube is another option, but in my experience it only works well on a tube that is absolutely cylindrical -- as is the case with solid-tube Newtonians and some other designs. The dew cap commonly found on refractors messes things up, because there's typically no clear sight line that aligns perfectly with the telescope's optical axis.

 

Moreover, this method works well only if you can get your eye to the back of the tube. In some cases, that may be physically impossible. In others, such as a Dob pointed high in the sky, it may require some skill as a contortionist (or lying down in the dew and getting drenched). Although I do use the sight-down-the-tube method when the batteries in my red-dot finders fail, I find a red-dot finder superior in all ways -- and at very moderate cost.

 

As you note in a later post, this is also possible using a straight-through finderscope if you keep both eyes open. However, I find this is only really accurate if my target is a bright naked-eye object. For pointing to a planet, for instance, I watch the naked-eye view through one eye converge on the view through the finderscope using the other eye, and they meet almost precisely when the planet is at the crosshairs.

 

I cannot get a straight-through finderscope very accurate for pointing to a known, but otherwise blank, piece of sky. For instance, I know precisely where M13 lies with respect to the four stars of the Keystone. I can land on that spot within a degree or so using a red-dot, red-circle, or laser-pointer finder. With a straight-through finderscope, I would expect much lower accuracy. On the other hand, since M13 is visible with even the slightest optical aid in all but the worst skies, I would be able to confirm and refine the pointing using the finderscope, but not with the other three methods.

 

There are many other tricks in a star-hoppers bag above and beyond the initial sighting at a known spot in the sky, but none of them work nearly as quickly. This assumes that the point-at-known-spot method works at all, which is not necessarily the case. In general, I find it useful only for objects that are reasonably bright and big.


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