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Do You Really need an ~80mm in the Stable?

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#76 GOLGO13

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Posted 20 May 2020 - 07:51 AM

The dwarfstar really helps for portability. Just has the be the right larger scope and the 4 inch F5 fits that bill.



#77 laedco58

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Posted 20 May 2020 - 08:08 AM

Nope...

but I have one.lol.gif



#78 Mvillegas

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Posted 20 May 2020 - 09:42 AM

Thanks for all the responses.  Closing in on buying a SkyWatcher 80ED and thinking of mounting on my C8 and use either as:

1) a guidescope for C8 or 

2) Dedicated Imaging Scope if not imaging on C8

 

Does anyone know if I need to align the center focal point of the Skywatcher with the center of the focal point of the C8 to use as a Guide scope or if its sitting ontop of C8, it should have a wide enough view to guide off a star in the same frame as the C8.

 

The answer will determine what type of mount I will use to piggy back on C8.  

 

My preference would be to use the vixen mount on ED80 to mount on C8 but then I can't adjust to alighn with C8.  If I need to perform alignment, I would need to buy rings to mount the ED80.

 

To further complicate things, I would envision the ED 80 riding piggy back on C8 as its guidescope and and smaller guidescope attached to ED80 for when I use the ED80 standalone.

 

Advice welcome! Thanks



#79 YAOG

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Posted 20 May 2020 - 03:06 PM

Thanks for all the responses.  Closing in on buying a SkyWatcher 80ED and thinking of mounting on my C8 and use either as:

1) a guidescope for C8 or 

2) Dedicated Imaging Scope if not imaging on C8

 

Does anyone know if I need to align the center focal point of the Skywatcher with the center of the focal point of the C8 to use as a Guide scope or if its sitting ontop of C8, it should have a wide enough view to guide off a star in the same frame as the C8.

 

The answer will determine what type of mount I will use to piggy back on C8.  

 

My preference would be to use the vixen mount on ED80 to mount on C8 but then I can't adjust to alighn with C8.  If I need to perform alignment, I would need to buy rings to mount the ED80.

 

To further complicate things, I would envision the ED 80 riding piggy back on C8 as its guidescope and and smaller guidescope attached to ED80 for when I use the ED80 standalone.

 

Advice welcome! Thanks

What mount are you planning to use? 

 

Don't mount the ED80 on top of a C8, it is always going to put one or the other scope in a bad location that will put a crick in your neck. Mount them Side-By-Side, look for a used Losmandy or ADM SBS mount, they go for about $150 or so. This lets you mount them at the same time if you want to  have the best of both worlds on the same EQ mount and still allows you to mount the ED80 as a single scope without having to buy two sets of ring mounts and change mounting if you want to use the ED80 alone visually or to image with.   

 

Guiding an SCT by most accounts works much more reliably if you use an OAG to autoguide. That said I have had good results using a 50mm f/4 guide scope piggybacked on the LX200 M10" f/6.3 SCT but my guidescope uses a non-adjustable clamshell that I shimmed to get aligned so it is pointed roughly at the same point. But I still recommend what most people will for guiding an SCT, OAG, skip the pain and jump to a known to work solution. I also recommend using whatever OAG is sold by the company that makes your cooled astro camera, ZWO for example has an excellent system that if you buy the ZWO autoguider camera and ZWO OAG and use a ZWO astro camera all the parts you need to get it setup are included, just screw it together following the clear directions and it just works. 

 

Don't complicate anything you don't absolutely have to and life will be better. The same is true for astronomy.  


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#80 213Cobra

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Posted 20 May 2020 - 06:04 PM

For nearly 30 years, my minimum desired aperture was 160mm or ~6.3". That was also my maximum desired aperture. I got the most compact form of that aperture in a Takahashi Epsilon 160 hyperbolic astrograph I use visually. f/3.3, flat field, robust, beautiful. There was so much planet  and lunar imagery around I turned my attention to the objects outside our solar system. The Newtonian astrograph still worked great for the moon. I could boost magnification for Jupiter and Saturn in the right years. But it was the black sky that had most of my attention. Plus, refractors in the 80s were slow and finicky or new and fast, still finding their footing.

 

A few years ago, on the tailwind of cataract surgery, better sight, learning about DioptRx and curious about modern refractors I decided to reboot and reinvest in this hobby, while keeping my treasured Epsilon. Knowing its lineage and reputation, I popped for an 80mm f/6 LOMO triplet to get my feet wet in refractors after a nearly 50 years hiatus from that optical type. It made a dang good impression on me, especially after I slipped a TSFlat2 flattener in it. That LOMO impressed me so much, I took a flyer on the f/7.5 80mm version just for the experience of comparing them side by side. But then I got what I really wanted in the first place, a Takahashi FSQ-85ED flat field astrograph quad. Still, the LOMOs have a character all their own so until I cannot, I have kept them. But my most-used scope is my FSQ-85ED.

 

From a device management perspective, I have no desire for a larger telescope, with the exception I'd consider an Epsilon 180 since at f/2.8 it is not much larger than the f/3.3 Epsilon 160. But I have traveled down the path to smaller apertures. 160>106>85>80>80>60>60>51, and none have been redundant in my observing. They just become more specific tools and / or pleasures. To the person who says they have a 130mm refactor, asking whether they need a 100mm, my answer is yes, if you consider "need" loosely. You wouldn't be asking if you can't afford it. Do you need an 80mm? Not if you have a 72 or 90mm but there is a significant convenience factor notching down from 100mm. People here ask whether they need a 60mm scope. Well, if you don't have one, a Tak FOA-60Q can be quite instructive and illuminating. I didn't think I needed a RedCat 51 v2 for visual either. But I was curious enough to try one. Now it's my favorite way to see quickly all the visible smudgies cutting through the L.A. light dome and dust. If I'm time-constrained or just lazy, that's enough. Otherwise it's a great tool for where to aim narrower-field, larger-aperture scopes. I love my RedCat 51 for visual.

 

Phil


Edited by 213Cobra, 20 May 2020 - 06:06 PM.

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#81 Gene3

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Posted 20 May 2020 - 06:54 PM

Back in January I felt the "need" to cover all my imaging possibilities so I got an SVX080-3SV (480mm FL, f/6) to complement my SVX152T (1200mm FL, f/8). I figured there would be times when targets would favor the SVX080 over the SVX152T.

Well I was wrong. I think that the SVX080 would have been a great scope to start with, but for me now I like the longer FL of my SVX152T, so I ended up selling the SVX080.

No regrets


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#82 Jon Isaacs

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Posted 23 May 2020 - 09:22 AM

Well, no one “needs” a telescope at all. But the poster is not asking if he “needs” a small telescope like someone "needs" food, he is asking if an 80 mm is the “right” small telescope, or are there better alternatives. And yes, there are better alternatives.

I recommend going back and reading the original post. That's not what Mauricio asked.  In fact, his question is primarily about a scope for imaging.

 

You point to your 102 mm F/5 as being as portable as an 80 mm APO.. I point to my ST-80 with it's 2 inch Focuser as being far more portable than any 90-100m apo or achromat. And it does things and goes places not possible visually with a larger scope. 

 

I get it that you prefer a larger scope. But I also understand that the alternatives you propose cost thousands of dollars and are realistically not as portable nor as handy. 

 

If someone wants to know why not to buy an 80 mm F/6 or F/7 ed/apo, I'll tell them to ask you. You can explain they can spend thousands of dollars to try to achieve the portability of an 80mm F/6-F/7 ed/apo with a slightly/somewhat larger scope.

 

If someone is interested in buying one,  I will share my thoughts and experiences with 70 mm, 80mm, as well as 100mm and 120mm Ed/Apos. Personally I think an 80 mm + 120-130 mm is a better combination than a 100 mm + 120-130mm.

 

There's a place for them all. 

 

A short story: 

 

Thursday I was lifting something and hurt my right bicep. It still hurts, it may take a while to heal. This meant no big Dobs, it meant no TV NP-101.

 

I spent two an a half hours with my 80 mm F/6 Ed/apo because I could lift it on its mount with only my left hand. I saw the Venus-Mercury conjunction and Venus as a 4.7% illuminated crescent. I love the thin crescent phase of Venus.. this is not achromat territory.

 

I then viewed some easy doubles, Castor, Porrima, the Double-Double, Izar. As the sky darkened, I started looking at DSOs, Omega Centauri, Centaurus A, a variety of Messier's, the Antenna Galaxies, NGC4361 (the 11th magnitude planetary in Corvus), NGC 5907, stuff like that.

 

A 4 inch ed/apo would have given a similar view of Venus-Mercury, similar views of the doubles, gone a little deeper on the DSOs. But it wouldn't have been steady and solid on any mount I've ever seen that I could carry one handed..

 

Had I not hurt my arm, I'd have been observing these and m many others in the 22 inch. The 80 mm provided way different views

than I'm used to.

 

As it was I was very satisfied with the night. In fact, it was a very special night.. Had I not hurt my arm, it would have "just been another night" under dark skies with the 22 inch hunting down faint galaxies, Nebulae and clusters as well as enjoying photo like views of brighter objects.

 

As it was, I was happy to see what I did see.. 

 

Yes, in my harem, there's definitely a place for a good 80 mm ed/apo.

 

Jon


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#83 Abb

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Posted 23 May 2020 - 10:03 AM

I've had my ST80 for about 5 years and would never part with it!! I have it permanently mounted on a tripod and can have it out in about a couple of minutes.

 

Go for it!

Abb


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#84 bobhen

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Posted 23 May 2020 - 12:20 PM

I recommend going back and reading the original post. That's not what Mauricio asked.  In fact, his question is primarily about a scope for imaging.

 

You point to your 102 mm F/5 as being as portable as an 80 mm APO.. I point to my ST-80 with it's 2 inch Focuser as being far more portable than any 90-100m apo or achromat. And it does things and goes places not possible visually with a larger scope. 

 

I get it that you prefer a larger scope. But I also understand that the alternatives you propose cost thousands of dollars and are realistically not as portable nor as handy. 

 

If someone wants to know why not to buy an 80 mm F/6 or F/7 ed/apo, I'll tell them to ask you. You can explain they can spend thousands of dollars to try to achieve the portability of an 80mm F/6-F/7 ed/apo with a slightly/somewhat larger scope.

 

If someone is interested in buying one,  I will share my thoughts and experiences with 70 mm, 80mm, as well as 100mm and 120mm Ed/Apos. Personally I think an 80 mm + 120-130 mm is a better combination than a 100 mm + 120-130mm.

 

There's a place for them all. 

 

A short story: 

 

Thursday I was lifting something and hurt my right bicep. It still hurts, it may take a while to heal. This meant no big Dobs, it meant no TV NP-101.

 

I spent two an a half hours with my 80 mm F/6 Ed/apo because I could lift it on its mount with only my left hand. I saw the Venus-Mercury conjunction and Venus as a 4.7% illuminated crescent. I love the thin crescent phase of Venus.. this is not achromat territory.

 

I then viewed some easy doubles, Castor, Porrima, the Double-Double, Izar. As the sky darkened, I started looking at DSOs, Omega Centauri, Centaurus A, a variety of Messier's, the Antenna Galaxies, NGC4361 (the 11th magnitude planetary in Corvus), NGC 5907, stuff like that.

 

A 4 inch ed/apo would have given a similar view of Venus-Mercury, similar views of the doubles, gone a little deeper on the DSOs. But it wouldn't have been steady and solid on any mount I've ever seen that I could carry one handed..

 

Had I not hurt my arm, I'd have been observing these and m many others in the 22 inch. The 80 mm provided way different views

than I'm used to.

 

As it was I was very satisfied with the night. In fact, it was a very special night.. Had I not hurt my arm, it would have "just been another night" under dark skies with the 22 inch hunting down faint galaxies, Nebulae and clusters as well as enjoying photo like views of brighter objects.

 

As it was, I was happy to see what I did see.. 

 

Yes, in my harem, there's definitely a place for a good 80 mm ed/apo.

 

Jon

I recommend going back and reading the original post. That's not what Mauricio asked.  In fact, his question is primarily about a scope for imaging.

 

I would not recommend any 70 or 80 mm semi-fast refractor for planetary imaging. A 100 mm would be better. And if one ventured outside refractor world, a 6”-8” SCT would be even better. Some 4" class apos, like the Borg 107 mm, can be made extremely fast for imaging, and are still lightweight. Borg deigns their scopes for travel. 

 

You point to your 102 mm F/5 as being as portable as an 80 mm APO.. I point to my ST-80 with it's 2 inch Focuser as being far more portable than any 90-100m apo or achromat. And it does things and goes places not possible visually with a larger scope.

 

What is you definition of “FAR” more portable. Some 90 and 107 mm apos are lightweight or modular or both for easy portability and convenient travel. My 102 F5 will be as portable as your ST-80 mm in all situations, but will gather more light.

 

I get it that you prefer a larger scope. But I also understand that the alternatives you propose cost thousands of dollars and are realistically not as portable nor as handy.

 

Yes some cost more. And that is a concession. But with an 80 mm apo (when compared to larger alternative) one is conceding performance. There is no right or wrong here just differences in what people value. One values money or one values more performance. You can’t have both. 

 

If someone wants to know why not to buy an 80 mm F/6 or F/7 ed/apo, I'll tell them to ask you. You can explain they can spend thousands of dollars to try to achieve the portability of an 80mm F/6-F/7 ed/apo with a slightly/somewhat larger scope.

 

Or they could get a 60 mm apo and have "even better portability" and "spend even less" than a 80mm apo. Of course they would also get "less performance" just as an 80 mm will deliver less performance than a 100mm. So if they want "ultimate portability" an 80 mm is not the answer – "a 60 mm apo is". And if they want "ultimate performance" an 80mm is also "not the answer" – a 100 mm apo that is" as portable and uses the same mount" as the 80mm is.

 

Personally I think an 80 mm + 120-130 mm is a better combination than a 100 mm + 120-130mm.

 

Personally, I think this is a better combination: binoculars then skip the 80 and get a lightweight 90 -107 mm – because a mount that holds an 80 mm will also hold a lightweight 90-107 mm. And then skip the 130 mm and get a 140 mm - because a mount that holds a 130 mm will also hold a 140 mm.

 

A short story:

 

Thursday I was lifting something and hurt my right bicep. It still hurts, it may take a while to heal. This meant no big Dobs, it meant no TV NP-101.

 

I spent two an a half hours with my 80 mm F/6 Ed/apo because I could lift it on its mount with only my left hand. I saw the Venus-Mercury conjunction and Venus as a 4.7% illuminated crescent. I love the thin crescent phase of Venus.. this is not achromat territory.

 

I then viewed some easy doubles, Castor, Porrima, the Double-Double, Izar. As the sky darkened, I started looking at DSOs, Omega Centauri, Centaurus A, a variety of Messier's, the Antenna Galaxies, NGC4361 (the 11th magnitude planetary in Corvus), NGC 5907, stuff like that.

 

A 4 inch ed/apo would have given a similar view of Venus-Mercury, similar views of the doubles, gone a little deeper on the DSOs. But it wouldn't have been steady and solid on any mount I've ever seen that I could carry one handed..

 

I can carry my UO Macrostar one-handed (if I had to) and that would easily hold any 4” apo. It easily holds my Tak TSA 120. In most cases portability is about the mount. And in most cases, anything that will hold an 80mm apo will also hold “the right” lightweight 4” apo or achromat, so there is no portability penalty for using the larger scope –  but there is a nice performance gain. 

 

Bob


Edited by bobhen, 23 May 2020 - 12:22 PM.


#85 Jacques

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Posted 23 May 2020 - 12:38 PM

Seriously thinking about adding an ST 80 as a rich field scope. It's quite cheap, yet it should be fantastic for this purpose. 


Edited by Jacques, 23 May 2020 - 12:45 PM.

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#86 howardcano

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Posted 23 May 2020 - 01:57 PM

I would not recommend any 70 or 80 mm semi-fast refractor for planetary imaging. A 100 mm would be better. And if one ventured outside refractor world, a 6”-8” SCT would be even better.

 

The OP stated that he already has a 127mm Apo and a C8, so I would guess that the 80mm would never be used for planetary imaging.  However, the 80mm would give a wider imaging field than either the 127mm or the C8.


Edited by howardcano, 23 May 2020 - 01:59 PM.

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#87 j.gardavsky

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Posted 23 May 2020 - 03:26 PM

I currently have 2 scopes:

 

1) a 127mm APO which can be paired with a .8 Reducer/Flattener 

2) a C8 which can be paired with a .63 Reducer 

 

Do you all find much use for something in 70mm-80mm range?  I typically image DSO's and planetary.

 

Thanks,

 

Mauricio

Returning to the OP, and the both telescopes he already has,

 

a fast ED (or APO) 72mm or 82mm would make sense for imaging the large nebulae, and eventually for the goups of galaxies.

 

For visual, an 82mm double refractor with a case filled with pairs of ultrawide eyepieces would be a nice instrument, when the costs don't play a role. Two eyes see more, especially when the aperture is not big.

 

Best,

JG


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#88 Bomber Bob

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Posted 23 May 2020 - 04:08 PM

I really don't need an 80mm refractor, when I have larger refractors that are just as easy to use with much more capability...

 

5" F5 non-ED triplet:

 

ATM 5x5T - Restore S31 (Meade Blue 60mm Finder).jpg

 

AT102ED F7 + Tak FC-50 F8:

 

AT102ED S21 RS (Mizar SP & FC-50).jpg

 

 


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#89 jimandlaura26

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Posted 23 May 2020 - 08:55 PM

From what I've learned in my very short time of researching for my own use, in astrophotography it's all about the mount.

 

And a fast 80 is much more stable on my "beginner" AVX mount than a larger scope...for DSO that is.

 

And long and slow is the ticket for planetary or lunar detail. High f/ratio four inchers with 5x barlow seem to be popular.

 

I would particularly like to add a small scope to my one and only AVX 6 refractor as a visual grab-n-go on a light manual alt/az mount for short outings where I may not want to hassle with loading up the big scope and mount, along with some power source for the Goto.

It’s about the mount even for visual observing! My most used scope, even though I have a variety - a Stellarvue SV-80S 80mm objective with 480mm focal length. Built like a tank, but rides exceptionally well on Discmounts DM-4 alt az and Celestron AVX GEM mounts.

Attached Thumbnails

  • 2BDB58B6-5FE3-40E4-B860-9FCDD206F39F.jpeg
  • 9655C433-E46D-4610-937A-F228D55E99BB.jpeg

Edited by jimandlaura26, 23 May 2020 - 09:07 PM.

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#90 bobhen

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Posted 24 May 2020 - 05:47 AM

I really don't need an 80mm refractor, when I have larger refractors that are just as easy to use with much more capability...

 

5" F5 non-ED triplet:

 

attachicon.gifATM 5x5T - Restore S31 (Meade Blue 60mm Finder).jpg

 

AT102ED F7 + Tak FC-50 F8:

 

attachicon.gifAT102ED S21 RS (Mizar SP & FC-50).jpg

That says it all.

 

Bob


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#91 Jon Isaacs

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Posted 24 May 2020 - 09:03 AM

Yes some cost more. And that is a concession. But with an 80 mm apo (when compared to larger alternative) one is conceding performance. There is no right or wrong here just differences in what people value. One values money or one values more performance. You can’t have both.

 

 

Cost is an important factor. Performance is measured in many ways. When thinking small, it can be a mistake to think bigger is better.. I have bigger is better well covered. 

 

In my world, these are small scopes, what they do better than larger scopes is the low power wide field stuff. They're handy. My 80 mm F/6 is 15 inches long, 17.5 inches with a 2 inch diagonal. It's compact with no assembly required. It fits nicely on the Bogen 3040..

 

Good luck hiking a half a mile with your TSA 120.. 

 

Good luck with the 100mm on the Bogan 3040..

 

The 60 mm is a red herring. It's another choice but the question here is whether there's a place for an 80 mm.  Binoculars... no filters, no high power, no photography.. 

 

I have a very good 4 inch. And I have a fast 4 inch achromat. In my world, there's also a place for a very good 80 mm as well as a fast 80 mm achromat. 

 

And there's a place for several other scopes.

 

Obsession with ladder 2014.jpg
 
In this photo, there's a nondescript refractor on a Vixen Portamount in the background. In the context of "performance", it didn't really matter whether it was an 80 mm or 102mm. It did the job..
 
Jon

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#92 YAOG

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Posted 24 May 2020 - 09:07 AM

I currently have 2 scopes:

 

1) a 127mm APO which can be paired with a .8 Reducer/Flattener 

2) a C8 which can be paired with a .63 Reducer 

 

Do you all find much use for something in 70mm-80mm range?  I typically image DSO's and planetary.

 

Thanks,

 

Mauricio

 

 

Returning to the OP, and the both telescopes he already has,

 

a fast ED (or APO) 72mm or 82mm would make sense for imaging the large nebulae, and eventually for the goups of galaxies.

 

For visual, an 82mm double refractor with a case filled with pairs of ultrawide eyepieces would be a nice instrument, when the costs don't play a role. Two eyes see more, especially when the aperture is not big.

 

Best,

JG

Thank you JG for leading it back to the OP's question. Nobody bothers to read and answer the OP's question around here. It's all that same people justifying their own purchases and point of view. 


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#93 bobhen

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Posted 24 May 2020 - 11:33 AM

 

Cost is an important factor. Performance is measured in many ways. When thinking small, it can be a mistake to think bigger is better.. I have bigger is better well covered. 

 

In my world, these are small scopes, what they do better than larger scopes is the low power wide field stuff. They're handy. My 80 mm F/6 is 15 inches long, 17.5 inches with a 2 inch diagonal. It's compact with no assembly required. It fits nicely on the Bogen 3040..

 

Good luck hiking a half a mile with your TSA 120.. 

 

Good luck with the 100mm on the Bogan 3040..

 

The 60 mm is a red herring. It's another choice but the question here is whether there's a place for an 80 mm.  Binoculars... no filters, no high power, no photography.. 

 

I have a very good 4 inch. And I have a fast 4 inch achromat. In my world, there's also a place for a very good 80 mm as well as a fast 80 mm achromat. 

 

And there's a place for several other scopes.

 

 
 
In this photo, there's a nondescript refractor on a Vixen Portamount in the background. In the context of "performance", it didn't really matter whether it was an 80 mm or 102mm. It did the job..
 
Jon

 

I wouldn’t hike with my TSA 120 – but I’m sure you knew that.  But I have hiked with my 102mm F-5 and that gives better performance than an ST-80 and with no portability penalty. And I could hike with a Borg 90 or Borg 107 or Tak Sky 90 or other light but larger refractors that will be just as portable as an 80mm but deliver more.

 

The 80mm proponents promote its portability. However if portability is an “absolute”, “number one” top priority, as it certainly can be, then a 60mm is the better choice over an 80mm. Remove performance as a top priority and being smaller takes the portability advantage. Add performance as a top priority and something that is larger BUT with the SAME portability as a 80mm is the better choice.

 

Cost is not a performance criterion. If you introduce a cost limit into the equation, then all the selections 60mm, 80mm and 90-plus mm will ALL have compromises? It will just depend on what compromise you are comfortable with: a portability compromise, a cost compromise or a performance compromise. As NONE of those apertures will check off ALL of the boxes when cost is considered.

 

In my world (even after owning 2, ST-80s, an 80mm apo Fluorite and the highly regarded and very sharp UO 80mm refractor) they were all bested, in one way or another by a larger refractor.

 

Bob


Edited by bobhen, 24 May 2020 - 11:45 AM.

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#94 Jon Isaacs

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Posted 24 May 2020 - 11:48 AM

In my world (even after owning 2, ST-80s, an 80mm apo Fluorite and the highly regarded and very sharp UO 80mm refractor) they were all bested, in one way or another by a larger refractor.

 

Bob

 

 

Chips point is a good one. This is our private battle and as I mentioned, we are not addressing the initial initial poster's question.

 

So I will say that after having owned numerous ST-80s, several with 2 inch focusers as well as a variety of other 80 mm scopes:

 

They all bested, in one way or another, other larger refractors. 

 

Jon


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#95 j.gardavsky

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Posted 24 May 2020 - 12:48 PM

There is also another aspect to the question

 

When you frequently travel by air with your astro equipment, a spotting scope or a commercial small double refractor, will be passed through the securities wihout questions. (My experience in Detroit Airport with a 77mm double refractor.)

Anything else what the securities have never seen before, may cause questions and some delay.

 

My 82mm Leica APO Televid suits in the smallest Deuter hiking bag, and so a small light weight tripod, binoculars, big atlas of skies, bottle for drink, ...

 

Best,

JG



#96 Bomber Bob

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Posted 24 May 2020 - 12:48 PM

To Get Back to The OP's Original Question:  Do you all find much use for something in 70mm-80mm range?

 

Yes, but it may be limited.

 

- My 80mm F5 to low-power / wide-field views -- the Big Fuzzies, the Milky Way, the Big Clusters.  Even in town, my vintage Meade 8" F6 Newt can show a lot of stuff, and this "super finder" helps me star-hop.

 

- My 1964 Astro Optical 76mm F15 is a fine example of imported Japan-made achromatic refractors.  Very low false color, textbook star tests, and superb resolution.  There are some double-stars where it is my preferred instrument -- Albireo comes to mind, but there are others.  My 1958 Goto 60mm F20 (same FL) is my best vintage Moon scope, but this 76mm isn't far behind.



#97 Jon Isaacs

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Posted 24 May 2020 - 12:56 PM

To Get Back to The OP's Original Question:  Do you all find much use for something in 70mm-80mm range?

 

 

That was the question I was answering. But the catch is original poster is primarily an imager so the visual virtues of an 80 mm seem to be irrelevant.

 

Jon



#98 gwlee

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Posted 24 May 2020 - 01:34 PM

I find my 72mm f6 refractor is still useful for a few observing tasks despite having an 8” Dob and an 92mm f6.7 refractor at home.  I think it works better as terrestrial spotting scope. It’s easy to take on short hikes to see celestial events not visible from home (conjunctions, transits, eclipses, etc.), or any situation where portability trumps optical performance.

 

The 72mm is OK for casually viewing the moon and for white light solar observing too. It’s been a tough Winter and Spring weather wise, so the 72mm has been my most used scope for the last six months, but it will probably see much less use during the Summer and Fall. 

 

Since your smallest scope is 127mm rather than 92mm, you might find a 72-80mm scope handy for a few observing few tasks too. Don’t do AP, so won’t comment about it. 


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#99 REC

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Posted 24 May 2020 - 01:58 PM

80's make a great grab n' go scope on a AZ mount. I have a C80ED to compliment my 8" SCT. With a 24mm 68* it make a great sky sweeper and a wide VOV for Milky Way cruiser. Nice black background and pin point stars.


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#100 Volvonium

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Posted 25 May 2020 - 12:33 AM

Do you enjoy using telescopes and don't mind owning more than one?  If yes, then proceed to 80mm.

 

For visual Aperture always wins.  My big dobs and newts clobber my big refractors on cost and performance.  My big refractors consistently clobber smaller ones in performance. 

 

Small aperture refractors?  Very fun. The act of using a telescope is very enjoyable to me and eking performance out of smaller sizes is uniquely rewarding.  My 80mm f/7 triplet surprises me with how similar its performance is with some of my longer scopes.  It keeps up with my 76.2mm f/15.7 Tasco 10TE-5 on double planets and stars, and can even keep up with my 101mm f/5.4 Televue Petzval on all targets, except on nights of good seeing.  It won't replace either scopes, since the others have their charms. 

 

Your mileage may vary, but with realistic expectations, I greatly enjoy what small scopes can provide.  One can simply spend money, find the best and call it a day, but I suspect many users extract enjoyment out of discovering how each telescope configuration works for them.

 

I don't do imaging, but I've seen what small apertures can do in the right hands.


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