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Best Large Dob Multi Function Finder Scope

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#1 DSO Viewer AZ

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Posted 14 September 2021 - 08:04 PM

Hey All, starting the H400. This will have some harder to find targets that will require better star hoping. I will be viewing some brighter objects in brighter skies, and harder to find in dark skies.This question is really for you larger Dob guys. 10-20+, as I have an XT10 F5, and a Hubble optics 18” F4.5. I run Telrads on both already and works very well. But learned during the Messier list that some targets and open clusters are larger than my scopes will allow to fit in eyepiece. Even at 40mm 68 ES eyepiece. Here is the question, If you wanted a fine quality finder scope that both helped star hopping, AND visual of larger targets, what would you experienced guys pick? 
Replaceable eyepiece vs built in?

Straight through vs Diagonal 

I think right side up, correct left to right is a requirement for the way I hunt.

I have done some searching but Love to know your thoughts of the higher end market and practicality of such an option.
Thanks in advance for any help… 

Clear Skies!

 



#2 Napp

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Posted 14 September 2021 - 08:18 PM

I use a dual mounted Telrad and 9X50 RACI.  the dual mount allows me to move the configuration to any of my scopes including the 10 inch and 16 inch DOB’s.  For me it’s a great combination for star hopping in light polluted skies and for searching for faint objects in dark skies.  It’s what I will use for the H400 which I plan to start once I can travel to my dark sky site again.

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#3 TOMDEY

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Posted 14 September 2021 - 08:19 PM

Actually... and seriously... right angle binoculars make a splendidly extravagant finder and wide-field rich field viewing for the big things. Here is my old 17.5-inch Dobsonian with 7x50 binos and my penta-mirror attachment. And also my 36-inch Dobsonian has both binos and now a 6-inch Apo Refractor where that cheesy Vixen used to be.    Tom

 

few pictures showing that stuff >>>

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#4 TOMDEY

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Posted 14 September 2021 - 08:20 PM

nother picture showing various finder/viewers >>>

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#5 DSO Viewer AZ

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Posted 14 September 2021 - 08:25 PM

I use a dual mounted Telrad and 9X50 RACI.  the dual mount allows me to move the configuration to any of my scopes including the 10 inch and 16 inch DOB’s.  For me it’s a great combination for star hopping in light polluted skies and for searching for faint objects in dark skies.  It’s what I will use for the H400 which I plan to start once I can travel to my dark sky site again.

Hey Napp,

Did you ever try RACI straight through on either of your scopes?
What model is the finder?

This is the idea. Nice set up!



#6 DSO Viewer AZ

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Posted 14 September 2021 - 08:29 PM

nother picture showing various finder/viewers >>>

I LOVE EVERYTHING GOING ON HERE!!!!  bow.gif

The bino idea never even crossed my mind but WOW!! I think I have some new goals!



#7 TOMDEY

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Posted 14 September 2021 - 08:30 PM

Here's another thing that's worth considering. It's a correct view spotting scope that has the nifty feature of on-the-fly adjustable deviation and also rotates in that mounting bracket --- all without losing pointing and no tools needed... a breeze for perfect ergonomics at all pointings in the hemisphere. It's also zoom and the eyepiece is dedicated. perfect as a finder/viewer.     Tom

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#8 TOMDEY

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Posted 14 September 2021 - 08:31 PM

nother image    Tom

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#9 DSO Viewer AZ

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Posted 14 September 2021 - 08:38 PM

Here's another thing that's worth considering. It's a correct view spotting scope that has the nifty feature of on-the-fly adjustable deviation and also rotates in that mounting bracket --- all without losing pointing and no tools needed... a breeze for perfect ergonomics at all pointings in the hemisphere. It's also zoom and the eyepiece is dedicated. perfect as a finder/viewer.     Tom

Well as soon as I get my mouth off the floor I’m going to look into this one! What a great idea thank you Tom!



#10 Napp

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Posted 14 September 2021 - 08:43 PM

Hey Napp,

Did you ever try RACI straight through on either of your scopes?
What model is the finder?

This is the idea. Nice set up!

Actually, no, and I have no plans to.  I don't have anything against a straight thru finder but my neck does.  You will notice in the picture that the Telrad is mounted on a 4 inch riser.  If I try to look through the Telrad mounted without the riser my neck lets me know real quick through pain and almost locking up that I should not do that.  With the riser I experience no pain or discomfort.  With the RACI no pain or discomfort.  The Telrad puts me either right on top of my target or on top of the visible star pattern I need to see to begin zeroing in with the RACI and then to an appropriate eyepiece.  The RACI is a Celestron 9X50 remounted into an Explore Scientific mount.  I already had the RACI and have seen no reason to replace it.  I see others post about finders with replaceable eyepieces.  If I did not already have the Celestron I would consider one with a replaceable eyepiece.  



#11 DSO Viewer AZ

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Posted 14 September 2021 - 08:51 PM

Actually, no, and I have no plans to.  I don't have anything against a straight thru finder but my neck does.  You will notice in the picture that the Telrad is mounted on a 4 inch riser.  If I try to look through the Telrad mounted without the riser my neck lets me know real quick through pain and almost locking up that I should not do that.  With the riser I experience no pain or discomfort.  With the RACI no pain or discomfort.  The Telrad puts me either right on top of my target or on top of the visible star pattern I need to see to begin zeroing in with the RACI and then to an appropriate eyepiece.  The RACI is a Celestron 9X50 remounted into an Explore Scientific mount.  I already had the RACI and have seen no reason to replace it.  I see others post about finders with replaceable eyepieces.  If I did not already have the Celestron I would consider one with a replaceable eyepiece.  

I learned a long time ago, don’t risk the neck! Fascinating to have the telrad that high but that makes perfect since. And something to keep in mind on this adventure. Great insight, Thanks!



#12 turtle86

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Posted 14 September 2021 - 09:04 PM

Here's another thing that's worth considering. It's a correct view spotting scope that has the nifty feature of on-the-fly adjustable deviation and also rotates in that mounting bracket --- all without losing pointing and no tools needed... a breeze for perfect ergonomics at all pointings in the hemisphere. It's also zoom and the eyepiece is dedicated. perfect as a finder/viewer.     Tom

 

That looks like an awesome option!



#13 Jon Isaacs

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Posted 14 September 2021 - 10:20 PM

Here's another thing that's worth considering. It's a correct view spotting scope that has the nifty feature of on-the-fly adjustable deviation and also rotates in that mounting bracket --- all without losing pointing and no tools needed... a breeze for perfect ergonomics at all pointings in the hemisphere. It's also zoom and the eyepiece is dedicated. perfect as a finder/viewer.     Tom

 

I am not sure how much star hopping you do, I am a star hopper 100%.  For me, this would be a very poor choice for a finder. Here are some of the difficulties:

 

- Maximum field of view:  1.8 degrees.  This is not much wider than the 1.3 degrees possible with a 18 inch F/4.5 and the 40 mm ES 68 degree.  

 

- No cross hairs.

 

- Difficult to align.  For star hopping, precise alignment with the main scope is critical.  

 

I spend a lot of time observing from the high desert with my 16 inch and 22 inch as well as from from my backyard in San Diego.  So far this year, I have logged 136 nights.. All star hopping.  What I have found works for me:

 

-  For me, the absolute minimum field of view for a finder scope is 4.0 degrees and I very much prefer 6 degrees or more.

 

-  I want a finder eyepiece with cross hairs that is quite well corrected and can be rotated so I can align the cross hairs with the altitude and azimuth cross hairs of the scope.  Ideally, the finder uses 1.25 inch eyepieces.  

 

This is what I use:

 

- 50 mm StellarVue RACI finder.  It has a 200 mm focal length and decent optics.  I am using the StellarVue rings, I use this with all my scopes.  I have 70 mm and 80mm RACI finders but I find I am more effective with the 50mm because of the wider field of view. There are plenty of stars to see.

 

StellarVue finder on 22 inch.jpg

 

- My primary finder eyepiece is an Explore Scientific 20mm 68degree with custom (hand made by me) cross-hairs.  This provides about 6.4 degrees at 10x.  It's not sharp across the field but sharper than any finder eyepiece I could buy.  I also have a 24mm TeleVue wide field fitted with cross hairs that provides a 6.8 degree field at 8.3x.  

 

-  I use SkySafari Pro on a Tablet. I align the finder by first centering it and then to the alt-az axes of the sky and scope.  On a Dob, the focuser of an RACI finder is not typically pointed vertically or horizontally so what seems like up-down and right-left in the finder is not.  By aligning the cross-hairs with the axes of the scope, I know what up-down and right-left are.  This is a post where I discuss this and how I plan a star hop:

 

https://www.cloudyni.../#entry11327469

 

With these techniques, very often I will be using 160x-260x as my "finder eyepiece" in my 16 inch and 216x-350x in the 22 inch.  These are Ethos eyepieces so they offer a wide field of view but the true fields are quite narrow, ranging from about 0.6 degrees to about 0.28 degrees.  That advantage of precise star hopping with the finder is that I am able to use high magnifications in the main scope so I can see those tiny faint galaxies and planetary's that would not be visible at lower magnifications.

 

Anyway, this is what works for me. 

 

Jon


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#14 CHASLX200

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Posted 15 September 2021 - 06:04 AM

I am not sure how much star hopping you do, I am a star hopper 100%.  For me, this would be a very poor choice for a finder. Here are some of the difficulties:

 

- Maximum field of view:  1.8 degrees.  This is not much wider than the 1.3 degrees possible with a 18 inch F/4.5 and the 40 mm ES 68 degree.  

 

- No cross hairs.

 

- Difficult to align.  For star hopping, precise alignment with the main scope is critical.  

 

I spend a lot of time observing from the high desert with my 16 inch and 22 inch as well as from from my backyard in San Diego.  So far this year, I have logged 136 nights.. All star hopping.  What I have found works for me:

 

-  For me, the absolute minimum field of view for a finder scope is 4.0 degrees and I very much prefer 6 degrees or more.

 

-  I want a finder eyepiece with cross hairs that is quite well corrected and can be rotated so I can align the cross hairs with the altitude and azimuth cross hairs of the scope.  Ideally, the finder uses 1.25 inch eyepieces.  

 

This is what I use:

 

- 50 mm StellarVue RACI finder.  It has a 200 mm focal length and decent optics.  I am using the StellarVue rings, I use this with all my scopes.  I have 70 mm and 80mm RACI finders but I find I am more effective with the 50mm because of the wider field of view. There are plenty of stars to see.

 

 

 

- My primary finder eyepiece is an Explore Scientific 20mm 68degree with custom (hand made by me) cross-hairs.  This provides about 6.4 degrees at 10x.  It's not sharp across the field but sharper than any finder eyepiece I could buy.  I also have a 24mm TeleVue wide field fitted with cross hairs that provides a 6.8 degree field at 8.3x.  

 

-  I use SkySafari Pro on a Tablet. I align the finder by first centering it and then to the alt-az axes of the sky and scope.  On a Dob, the focuser of an RACI finder is not typically pointed vertically or horizontally so what seems like up-down and right-left in the finder is not.  By aligning the cross-hairs with the axes of the scope, I know what up-down and right-left are.  This is a post where I discuss this and how I plan a star hop:

 

https://www.cloudyni.../#entry11327469

 

With these techniques, very often I will be using 160x-260x as my "finder eyepiece" in my 16 inch and 216x-350x in the 22 inch.  These are Ethos eyepieces so they offer a wide field of view but the true fields are quite narrow, ranging from about 0.6 degrees to about 0.28 degrees.  That advantage of precise star hopping with the finder is that I am able to use high magnifications in the main scope so I can see those tiny faint galaxies and planetary's that would not be visible at lower magnifications.

 

Anyway, this is what works for me. 

 

Jon

That is how like my finder close by the focuser. I don't do much deep sky but a 80mm does the trick for me as long as balance is not thrown off.



#15 Redbetter

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Posted 15 September 2021 - 06:34 AM

For a large Dob and the H400 I favor an 80mm finder scope with RACI diagonal.  I use an ST80 with 24 or 25mm eyepiece on the 20" f/5, yielding 3.5 to 3.8+ degrees depending the eyepiece.  I can actually see many of the the H400 this way in dark sky if I look carefully--keep in mind this is only 16 to 17x and further magnification would be useful for seeing them directly, but sacrifice true FOV.   I am visual only for finding/star hopping.  I don't need a cross hair in the eyepiece, I eyeball alignment.

 

There are negatives to this.  The finder/diagonal/eyepiece is heavy and requires a lot of counterbalance weight at f/5, roughly a 5x factor per pound mounted on the UTA.  It won't work with all assemblies. and is not "one size fits all."  This is pretty wide, with a useful limiting magnitude 1-2 mag beyond Uranometria for the magnfication which matches my needs.

 

A 70 would work, but they don't operate near full aperture, so what would be the point of the weight penalty?  60mm is reported to have similar problems, which puts us at 50...one of two choices in the larger scope range.  A 50 is wider, but not sufficient magnification or light grasp for my needs.  I like an 80 serving as a finder as well as an RFT on my 20".

 

I get in around 60+ dark sky nights per year and I try to make each one count.


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#16 DSO Viewer AZ

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Posted 15 September 2021 - 07:48 AM

I am not sure how much star hopping you do, I am a star hopper 100%.  For me, this would be a very poor choice for a finder. Here are some of the difficulties:

 

- Maximum field of view:  1.8 degrees.  This is not much wider than the 1.3 degrees possible with a 18 inch F/4.5 and the 40 mm ES 68 degree.  

 

- No cross hairs.

 

- Difficult to align.  For star hopping, precise alignment with the main scope is critical.  

 

I spend a lot of time observing from the high desert with my 16 inch and 22 inch as well as from from my backyard in San Diego.  So far this year, I have logged 136 nights.. All star hopping.  What I have found works for me:

 

-  For me, the absolute minimum field of view for a finder scope is 4.0 degrees and I very much prefer 6 degrees or more.

 

-  I want a finder eyepiece with cross hairs that is quite well corrected and can be rotated so I can align the cross hairs with the altitude and azimuth cross hairs of the scope.  Ideally, the finder uses 1.25 inch eyepieces.  

 

This is what I use:

 

- 50 mm StellarVue RACI finder.  It has a 200 mm focal length and decent optics.  I am using the StellarVue rings, I use this with all my scopes.  I have 70 mm and 80mm RACI finders but I find I am more effective with the 50mm because of the wider field of view. There are plenty of stars to see.

 

 

 

- My primary finder eyepiece is an Explore Scientific 20mm 68degree with custom (hand made by me) cross-hairs.  This provides about 6.4 degrees at 10x.  It's not sharp across the field but sharper than any finder eyepiece I could buy.  I also have a 24mm TeleVue wide field fitted with cross hairs that provides a 6.8 degree field at 8.3x.  

 

-  I use SkySafari Pro on a Tablet. I align the finder by first centering it and then to the alt-az axes of the sky and scope.  On a Dob, the focuser of an RACI finder is not typically pointed vertically or horizontally so what seems like up-down and right-left in the finder is not.  By aligning the cross-hairs with the axes of the scope, I know what up-down and right-left are.  This is a post where I discuss this and how I plan a star hop:

 

https://www.cloudyni.../#entry11327469

 

With these techniques, very often I will be using 160x-260x as my "finder eyepiece" in my 16 inch and 216x-350x in the 22 inch.  These are Ethos eyepieces so they offer a wide field of view but the true fields are quite narrow, ranging from about 0.6 degrees to about 0.28 degrees.  That advantage of precise star hopping with the finder is that I am able to use high magnifications in the main scope so I can see those tiny faint galaxies and planetary's that would not be visible at lower magnifications.

 

Anyway, this is what works for me. 

 

Jon

Hey Jon, this is very insightful. Thank you. I agree with the cross hairs, I was looking at illuminating eyepieces, but I am a explore scientific kind of guy, and as of now I’m not aware of them offering such a thing. Orion seems to have one with a nice FOV would be interested in quality. Would love to know how / where you put in cross hairs on your eyepiece, have you tried the illuminated eyepieces? Also, I noticed your finder scope is located very very close to your focuser (nice configuration by the way). How do you like that position? Do you use your finder scope for any wide field viewing? 
Drew



#17 Jon Isaacs

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Posted 15 September 2021 - 09:28 AM

Hey Jon, this is very insightful. Thank you. I agree with the cross hairs, I was looking at illuminating eyepieces, but I am a explore scientific kind of guy, and as of now I’m not aware of them offering such a thing. Orion seems to have one with a nice FOV would be interested in quality. Would love to know how / where you put in cross hairs on your eyepiece, have you tried the illuminated eyepieces? Also, I noticed your finder scope is located very very close to your focuser (nice configuration by the way). How do you like that position? Do you use your finder scope for any wide field viewing? 
Drew

 

Drew:

 

- I have owned a number of illuminated reticule eyepieces including the AgenaAstro version of the Orion 20 mm 70 degree.  I dislike them. They illumination bleeds into the field, they're fragile and unnecessary. They also an Erfle derivative or something and quite a mess off axis.

 

The 20 mm 70 degree was my last purchase. After trying it out, I decided there commercial eyepieces were hopeless and decided I had to modify existing wide field eyepieces. The first one I did was the 24 mm TV Widefield. The cross hairs are placed at the focal plane so they're in focus. That means attaching them to the field stop. The field stop has to be wide enough to glue the wire to. Eyepieces like the 24 mm Panoptic barely have a field stop, too narrow. It's difficult work because you're working inside the barrel.

 

The usual problem with unilluminated cross hairs is that they disappear under dark skies. This is just because the cross hairs at too thin, bad design. Thicker wire, I use 0.004" hard brass EDM wire, is easily seen even under the darkest skies.  Last week I was at the Navajo National Monument. Directly overhead was the Milky Way. Pointed directly at the Milky Way, I was reading 21.82 mpsas on my SQM. Pointed at the darkest sky, 21.9. I had no trouble seeing the cross hairs.

 

Positioning the finder relative to the focuser is important. It needs to be close so that it's easy to work between the main scope eyepiece and the finder but not so close that they interfere.  I use 6 screw mounting rings so I can slide the finder in the rings to position the finder.

 

I do use the finder as a mini RFT, sometimes using filters. I use my refractors less now, the 50 mm does a good job.

 

Regarding finder aperture:

 

As I said, I have 50mm, 70mm and 80mm RACI finders.  Both the 70mm and the 80mm were reworked so they operate at full aperture.  The 70mm is an Orion Multi-Use finder with the objective replaced with a Japanese Carton 70mm F/4.5 air spaced objective from Sheldon Farowski.  I am using AgenaAstro rings.  The complete finder weighs 29 ounces minus eyepiece. Optically, it is very good (not many finders split the double-double) and with the 24mm TeleVue wide field, it provides a 4.5 degree field at 13x, it's really a very nice view.

 

IMG_15092021_073417_(1024_x_700_pixel).jpg

 

The StellarVue 50mm finder weighs 19 ounces so that's only a difference of 10 ounces so it doesn't take a lot of counterweight to balance the scope. With an ST-80, you gain a little aperture but just the scope weighs 48 ounces and then with the diagonal and rings, it takes a lot of counterweight, at least 10 pounds with an Obsession style truss Dob. 

 

I always take the 70mm with me and I do use it some but I find that the 6.4 degree TFoV at 10 inch shows me plenty of stars and the wider field is a real advantage, it just works better for me.  But the 70mm, it's a good finder...

 

Jon



#18 Jimmy462

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Posted 15 September 2021 - 10:52 AM

Hi Drew, etal.,

 

To toss an alternative method for finding faint fuzzies into the mix (and the method I've been using since my copy of the Sky Atlas 2000 Laminated version arrived in the late'80s and augmented since with Uranometria 2000 for fainter schtuff!)...

 

Field desk, sky atlas(es) with Telrad overlay (as needed), binoculars to find my target field. Use Telrad on scope to center target field. Tweak eyepiece view and observe. I have zero, zilch, nada magnifying finders on any of my telescopes.

 

Other's experiences may vary. ;)

Jimmy G


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#19 Pierre Lemay

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Posted 15 September 2021 - 11:35 AM

Quinsight finder on 20 inch.jpeg

 

I started using the Quinsight this year and I like it very much. It's like a Telrad on a riser but with a larger window. It's also a natural fit for the eyepiece position on my 20 inch ball scope.

 

The picture above shows both the Quinsight and RACI on the UTA. Earlier this summer I found myself at a crossroad: do I keep the RACI or ditch it? I use to use the lighter weight Rigel as the reflex sight and things balanced out but the Quinsight is much heavier (300 g VS 60 g). The RACI plus its bracket weighs about 450g (one pound). When I take it off, the scope is well balanced. If I keep it and the Quinsight, I need to add another 5 or 6 pounds of ballast at the bottom of the tube. Since the telescope only weighs 82 pounds, that extra weight becomes significant.

 

With its multiple illuminated rings that span up to 16 degrees and the large viewing window, I rarely find it useful anymore to look through the RACI. Also, I placed the Quinsight just above the eyepiece turret. So whether I'm approaching the eyepiece from the left or the right the reflex finder is always conveniently located.

 

They say the main use for an optical finder is that it's easier to find objects in light polluted skies (which is where I do most of my observing). But, quite frankly, I don't find that to be the case. I find it much more natural to locate objects with both eyes opened looking through a reflex sight.

 

For now I've removed the RACI and it's working out quite well. My widest field eyepiece provides 1 full degree of view. Combined with the Quinsight, I'm able to star hop accross the sky with good efficiency.


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#20 Jon Isaacs

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Posted 15 September 2021 - 12:23 PM

Just a comment about the Quinsight:

 

Unlike the Telrad and the Rigel, the glass plate has unprotected edges. To me, that looks like an accident weighting to happen. 

 

Everyone has they're own way of doing things. For me, I find the RACI finder allows me to accurately point the scope at relatively high magnifications and avoid Starhopping in the main eyepiece. The object might be somewhere in the field of view of the main eyepiece at low magnifications but not be visible because there's just not enough magnification to see it.

 

For viewing the Herschel 400, this is probably not such an issue because they're not pushing the limits of an 18 inch but this thread is about the best finder scope for a large Dob and for me, a magnifying finder is important in accurately pointing the scope.

 

With a 10x finder with a 6.4 degree field, 40% of the Quinsight, but I have 10x magnification and it goes about 4 magnitudes deeper, lots of stars to use for alignment and most often I'm using stars very close to the object.

 

 

Jon


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#21 DSO Viewer AZ

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Posted 15 September 2021 - 03:00 PM

Drew:

 

- I have owned a number of illuminated reticule eyepieces including the AgenaAstro version of the Orion 20 mm 70 degree.  I dislike them. They illumination bleeds into the field, they're fragile and unnecessary. They also an Erfle derivative or something and quite a mess off axis.

 

The 20 mm 70 degree was my last purchase. After trying it out, I decided there commercial eyepieces were hopeless and decided I had to modify existing wide field eyepieces. The first one I did was the 24 mm TV Widefield. The cross hairs are placed at the focal plane so they're in focus. That means attaching them to the field stop. The field stop has to be wide enough to glue the wire to. Eyepieces like the 24 mm Panoptic barely have a field stop, too narrow. It's difficult work because you're working inside the barrel.

 

The usual problem with unilluminated cross hairs is that they disappear under dark skies. This is just because the cross hairs at too thin, bad design. Thicker wire, I use 0.004" hard brass EDM wire, is easily seen even under the darkest skies.  Last week I was at the Navajo National Monument. Directly overhead was the Milky Way. Pointed directly at the Milky Way, I was reading 21.82 mpsas on my SQM. Pointed at the darkest sky, 21.9. I had no trouble seeing the cross hairs.

 

Positioning the finder relative to the focuser is important. It needs to be close so that it's easy to work between the main scope eyepiece and the finder but not so close that they interfere.  I use 6 screw mounting rings so I can slide the finder in the rings to position the finder.

 

I do use the finder as a mini RFT, sometimes using filters. I use my refractors less now, the 50 mm does a good job.

 

Regarding finder aperture:

 

As I said, I have 50mm, 70mm and 80mm RACI finders.  Both the 70mm and the 80mm were reworked so they operate at full aperture.  The 70mm is an Orion Multi-Use finder with the objective replaced with a Japanese Carton 70mm F/4.5 air spaced objective from Sheldon Farowski.  I am using AgenaAstro rings.  The complete finder weighs 29 ounces minus eyepiece. Optically, it is very good (not many finders split the double-double) and with the 24mm TeleVue wide field, it provides a 4.5 degree field at 13x, it's really a very nice view.

 

attachicon.gifIMG_15092021_073417_(1024_x_700_pixel).jpg

 

The StellarVue 50mm finder weighs 19 ounces so that's only a difference of 10 ounces so it doesn't take a lot of counterweight to balance the scope. With an ST-80, you gain a little aperture but just the scope weighs 48 ounces and then with the diagonal and rings, it takes a lot of counterweight, at least 10 pounds with an Obsession style truss Dob. 

 

I always take the 70mm with me and I do use it some but I find that the 6.4 degree TFoV at 10 inch shows me plenty of stars and the wider field is a real advantage, it just works better for me.  But the 70mm, it's a good finder...

 

Jon

Hey Jon, this is a wealth of knowledge. smile.gif  I like the stellar view line looks about right. Being able to use existing high quality 1.25 eyepieces with filters is a BIG plus. Thanks for the heads up on weight. That is always something that slips through my imagination as I visualize how this would work. I do have weights on both scopes already to balance my huge ES 40mm EP. That thing weighs a ton…lol. Add on a super finder and I will have to dip into the Gym to steel some weight! Just out of curiosity, why the duck tape?
Appreciate all your help. 



#22 DSO Viewer AZ

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Posted 15 September 2021 - 03:21 PM

Hi Drew, etal.,

 

To toss an alternative method for finding faint fuzzies into the mix (and the method I've been using since my copy of the Sky Atlas 2000 Laminated version arrived in the late'80s and augmented since with Uranometria 2000 for fainter schtuff!)...

 

Field desk, sky atlas(es) with Telrad overlay (as needed), binoculars to find my target field. Use Telrad on scope to center target field. Tweak eyepiece view and observe. I have zero, zilch, nada magnifying finders on any of my telescopes.

 

Other's experiences may vary. wink.gif

Jimmy G

Hey Jimmy, this is the method I presently use and not to bad, however during the Virgo cluster search, I kept finding a mild missing link that I feel a quality mini refractor could help solve. I find my binos allow me to easily find where I need to point, but would like that ability attached right to the scope. (One less thing to carry on me around the eyepiece). Plus some of the larger objects would be cool to see, that my scope (and my coffee shaking hands holding binos) just doesn’t quite allow fully in the eyepiece. My 10” came with a finder scope but was one of the “cheaper” units, straight through and backwards. I took it off a few years ago and never looked back till just recently while thinking about adding a refractor to my line up. Then it just made more since to be able to use as a finder as well….  Maybe I’m just a little crazy. All just part of my astronomy path. shrug.gif 
Clear Skies!


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#23 Jimmy462

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Posted 15 September 2021 - 08:08 PM

Hey Jimmy, this is the method I presently use and not to bad, however during the Virgo cluster search, I kept finding a mild missing link that I feel a quality mini refractor could help solve. I find my binos allow me to easily find where I need to point, but would like that ability attached right to the scope. (One less thing to carry on me around the eyepiece). Plus some of the larger objects would be cool to see, that my scope (and my coffee shaking hands holding binos) just doesn’t quite allow fully in the eyepiece. My 10” came with a finder scope but was one of the “cheaper” units, straight through and backwards. I took it off a few years ago and never looked back till just recently while thinking about adding a refractor to my line up. Then it just made more since to be able to use as a finder as well….  Maybe I’m just a little crazy. All just part of my astronomy path. shrug.gif 
Clear Skies!

Hi Drew,

 

No doubt that certain targets pose challenges to my methodology, and navigating the Virgo Cluster is certainly the top example! Ha! Easy to get confused in there...and to get lost and have to start over again.

 

My big cheat for that is Hans Vehrenberg's Atlas of Deep Sky Splendors with its lovely large scale black-and-white photographic plates which are extremely helpful with getting one's bearings with all of the faint stars and micro-asterisms to help one verify their position at the eyepiece!

 

All a part of the challenge I so love with star-hopping and learning the lay of the, er, "land"!

 

Old dog, no new tricks. ;)

Jimmy G


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#24 Markovich

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Posted 15 September 2021 - 08:16 PM

I cheat nowadays..I gave up the optical finder for a Telrad and my iPad/AstroDevices Nexus II and encoders .

The Stellarvue RA 9x50 finder sits unused in my kit bag and the Sky Atlas is looked at on cloudy nights in my recliner.

 

The Nexus and iPad combination is such a game changer for me that I can observe many more objects in a single evening than ever before, especially from the suburban skies of my back yard.


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#25 ButterFly

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Posted 16 September 2021 - 12:51 AM

Hi Drew, etal.,

 

To toss an alternative method for finding faint fuzzies into the mix (and the method I've been using since my copy of the Sky Atlas 2000 Laminated version arrived in the late'80s and augmented since with Uranometria 2000 for fainter schtuff!)...

 

Field desk, sky atlas(es) with Telrad overlay (as needed), binoculars to find my target field. Use Telrad on scope to center target field. Tweak eyepiece view and observe. I have zero, zilch, nada magnifying finders on any of my telescopes.

 

Other's experiences may vary. wink.gif

Jimmy G

Now that I live under dark skies, I'm entirely Telrad or pulsed green laser.  Back in NYC, I needed the magnified finder.  The star-hops are a lot longer under light polluted skies, and there weren't too many other DSOs to use for "star" hopping.  For the 80mm, I can just sight along the side of the thing, but the pulsed laser keeps me from swapping eyepieces or bending to the side.


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