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Why do people even buy SCTs???

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#51 JJK

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Posted 29 November 2013 - 09:01 PM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


If you want aperture, get a Dob-Newt.
 

#52 JJK

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Posted 29 November 2013 - 09:03 PM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


Yeah, a 14" refractor would be a monster to be sure even if it was an APO. My C-9 is currently satisfying my large planetary scope needs. A 9" refractor could not be afforded even if I built my own hence my "modded" C-9. We all satisfy our needs in different ways.

Scopejunkie


While SCTs have their virtues, it would take much less than a 9" refractor to outperform a 9" SCT.
 

#53 ATM57

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Posted 29 November 2013 - 09:39 PM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


Yeah, a 14" refractor would be a monster to be sure even if it was an APO. My C-9 is currently satisfying my large planetary scope needs. A 9" refractor could not be afforded even if I built my own hence my "modded" C-9. We all satisfy our needs in different ways.

Scopejunkie


While SCTs have their virtues, it would take much less than a 9" refractor to outperform a 9" SCT.


Not mine.

Scopejunkie
 

#54 Dwight J

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Posted 29 November 2013 - 09:40 PM

I wonder why then so many of the best planetary imagers and images use and are taken by C11's and 14's. Must be their low contrast, huge obstruction, and mushy optics. Oh, I almost forgot their eons long cooling time.
 

#55 dscarpa

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Posted 29 November 2013 - 09:57 PM

The only issues my regular C9.25 has is a bit of image shift, a little coma and on a humid night it dews up before I can get it out the door. My scopes mount's a push to Unistar so no power but there's always a hair drier standing by! There's a lot less coma with the SCT than my new 11" F/5 newt without it's corrector. The newt has a high end mirror and should out perform the SCT with ease but what with viewing seated comfortably with the cat vs not sure yet with the newt that might not be the case for lunar-planetary in particular. On excellent nights I've used the C9.25 at 400X on Jupiter and 500X-550X on the Moon, Saturn and Mars with very detailed, crisp, bright high contrast images! David
 

#56 JJK

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Posted 29 November 2013 - 10:40 PM

I wonder why then so many of the best planetary imagers and images use and are taken by C11's and 14's. Must be their low contrast, huge obstruction, and mushy optics. Oh, I almost forgot their eons long cooling time.


I didn't say decent SCTs don't exist. As I alluded to above, I've been looking to add one to my visual scope aresenal, but stopped a decade or so ago because none I critically tested (C-11s) could be pushed over 250 x on nights that my AP Mak-Cass was easily able to work well at 400 to 600 x. I'm thinking of looking again with the advent of Hyperstar. Looks like a lot of fun.
 

#57 JJK

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Posted 29 November 2013 - 10:42 PM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


Yeah, a 14" refractor would be a monster to be sure even if it was an APO. My C-9 is currently satisfying my large planetary scope needs. A 9" refractor could not be afforded even if I built my own hence my "modded" C-9. We all satisfy our needs in different ways.

Scopejunkie


While SCTs have their virtues, it would take much less than a 9" refractor to outperform a 9" SCT.


Not mine.

Scopejunkie


Which 9" refractors did you test your 9" SCT against, and on which targets?
 

#58 jgraham

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Posted 29 November 2013 - 11:19 PM

I've got my 10" SCT outside right now taking images of Jupiter. Simply freek'n awesome.
 

#59 PowellAstro

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Posted 29 November 2013 - 11:33 PM

TOP TEN REASONS WE LOVE OUR SCTs

1..Because they are great scopes!

2..As far as comfort goes, no other scope comes close!

3..They also are more steady per pound than a GEM of the same aperture! (for the same amount of money)

4..They are also lighter per aperture than most any other computer driven scope!

5..With a day or two of work, they can be as good as almost any other design could possibly be, with the same amount of CO that is! (A Good Unit)

6..They look great! Who wants to use an ugly scope? Not me.

7..They are the most convenient!

8..There are all kinds of accessories for them!

9..They do visual, they do photography!

10..They don't cost an arm and a leg and a child to own!

So, all things considered, what's not to like???
 

#60 ATM57

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Posted 29 November 2013 - 11:37 PM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


Yeah, a 14" refractor would be a monster to be sure even if it was an APO. My C-9 is currently satisfying my large planetary scope needs. A 9" refractor could not be afforded even if I built my own hence my "modded" C-9. We all satisfy our needs in different ways.

Scopejunkie


While SCTs have their virtues, it would take much less than a 9" refractor to outperform a 9" SCT.


Not mine.

Scopejunkie


Which 9" refractors did you test your 9" SCT against, and on which targets?


I have built 3 8" refractors. Two at F/12 and 1 at F/9. I know how 8" refractors perform and would compare to my modified C-9.

Scopejunkie

Attached Thumbnails

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#61 BYoesle

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Posted 30 November 2013 - 12:34 AM

Great, just what we need: another petty and ridiculous sectarian divide.

First, let me say I’ve owned all kinds of telescopes. I don’t think it appropriate to disparage a particular type of telescope, as they all have their pluses and minuses. SCTs offer a large aperture in a compact size, among other advantages. However, they can also have their limitations and issues, and indeed often can be made to perform even better by modifying them – both optically and mechanically. Where does the concept of “believing in their SCTs” (or any telescope for that matter) come into play? Perhaps I’m just an atheist when it comes to material objects, or at least telescopes ;)

That said, I’m having a little trouble understanding your post Ed.

I have just been so thrilled with my SCTs in the past. Most of them were really able telescopes that presented me with hundereds of hours of wonderful observing. And none of the mods I tried seemed to make any meaningful difference for my own observing needs that I stopped chasing the "Mod of the day" a long time ago. And the bigger I went, the more I enjoyed them. The more I could see. More deep sky, more planetary detail, more stars in clusters. No mods or anything. I just went bigger and bigger and saw more and more... At least one person loves them just the way they are...


If you were so thrilled with the SCT’s you had in the past and loved them just the way they are, why did you get an Edge HD as listed in the signature? Could it have been OTA/mirror venting, a new secondary mirror and corrective optics to eliminate coma and flatten the field, and a primary mirror clutch/lock to eliminate mirror shift?

It seems you have “voted with your feet” and abandoned the very scopes you love “just the way they are.” So if someone with an older version SCT attempts via modification to gain some of the same advantages you have obtained by buying an newer version of the SCT, doesn’t that mean you have simply paid to have the mods done for you rather than attempting them yourself? Hasn’t your very action demonstrated that which you are concerned with -- enhancing the perception that there is “so much wrong” with SCTs? If you have chosen a “better mouse trap” via a manufacturer, why shouldn’t someone try some of the same via modification of their existing scope -- without being subjected to the claim that they are denigrating the SCT?

Lastly, let me just say some of us like to tinker and experiment to see what improvements we can make on our own, and how the incremental improvements can add up...

Best wishes to one and all,
 

#62 EFT

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Posted 30 November 2013 - 12:52 AM

My first real scope was an SCT and I doubt that I will ever be without one. They may not be perfect, but that cannot be beat for size, performance AND price. I have yet to feel the desire to haul around a 6-foot plus tube or a hugely heavy collapsible newt that must be completely disassembled for transport. Someday maybe, but I still won't give up my SCT. Nothing wrong with modding them to improve the performance, but even that may not be necessary depending on where you use the scope.
 

#63 azure1961p

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Posted 30 November 2013 - 01:36 AM

Great, just what we need: another petty and ridiculous sectarian divide.

First, let me say I’ve owned all kinds of telescopes. I don’t think it appropriate to disparage a particular type of telescope, as they all have their pluses and minuses. SCTs offer a large aperture in a compact size, among other advantages. However, they can also have their limitations and issues, and indeed often can be made to perform even better by modifying them – both optically and mechanically. Where does the concept of “believing in their SCTs” (or any telescope for that matter) come into play? Perhaps I’m just an atheist when it comes to material objects, or at least telescopes ;)

That said, I’m having a little trouble understanding your post Ed.

I have just been so thrilled with my SCTs in the past. Most of them were really able telescopes that presented me with hundereds of hours of wonderful observing. And none of the mods I tried seemed to make any meaningful difference for my own observing needs that I stopped chasing the "Mod of the day" a long time ago. And the bigger I went, the more I enjoyed them. The more I could see. More deep sky, more planetary detail, more stars in clusters. No mods or anything. I just went bigger and bigger and saw more and more... At least one person loves them just the way they are...


If you were so thrilled with the SCT’s you had in the past and loved them just the way they are, why did you get an Edge HD as listed in the signature? Could it have been OTA/mirror venting, a new secondary mirror and corrective optics to eliminate coma and flatten the field, and a primary mirror clutch/lock to eliminate mirror shift?

It seems you have “voted with your feet” and abandoned the very scopes you love “just the way they are.” So if someone with an older version SCT attempts via modification to gain some of the same advantages you have obtained by buying an newer version of the SCT, doesn’t that mean you have simply paid to have the mods done for you rather than attempting them yourself? Hasn’t your very action demonstrated that which you are concerned with -- enhancing the perception that there is “so much wrong” with SCTs? If you have chosen a “better mouse trap” via a manufacturer, why shouldn’t someone try some of the same via modification of their existing scope -- without being subjected to the claim that they are denigrating the SCT?

Lastly, let me just say some of us like to tinker and experiment to see what improvements we can make on our own, and how the incremental improvements can add up...

Best wishes to one and all,


I think you mis took his intent.

Pete
 

#64 JJK

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Posted 30 November 2013 - 01:46 AM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


Yeah, a 14" refractor would be a monster to be sure even if it was an APO. My C-9 is currently satisfying my large planetary scope needs. A 9" refractor could not be afforded even if I built my own hence my "modded" C-9. We all satisfy our needs in different ways.

Scopejunkie


While SCTs have their virtues, it would take much less than a 9" refractor to outperform a 9" SCT.


Not mine.

Scopejunkie


Which 9" refractors did you test your 9" SCT against, and on which targets?


I have built 3 8" refractors. Two at F/12 and 1 at F/9. I know how 8" refractors perform and would compare to my modified C-9.

Scopejunkie


Did you grind the lenses, what style (achro, apo) where they, and what were the specifications of the objectives (smoothness, zones, coatings)?
 

#65 ATM57

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Posted 30 November 2013 - 02:03 AM

I have had all ... refractors, apo's, reflectors, SCT's and sorry, aperture rules! A really sweet scope like my Meade 14"ACF is awesome. Imagine having a 14" refractor, oh my goodness, I'd need a crane to haul THAT around! :lol:


Yeah, a 14" refractor would be a monster to be sure even if it was an APO. My C-9 is currently satisfying my large planetary scope needs. A 9" refractor could not be afforded even if I built my own hence my "modded" C-9. We all satisfy our needs in different ways.

Scopejunkie


While SCTs have their virtues, it would take much less than a 9" refractor to outperform a 9" SCT.


Not mine.

Scopejunkie


Which 9" refractors did you test your 9" SCT against, and on which targets?


I have built 3 8" refractors. Two at F/12 and 1 at F/9. I know how 8" refractors perform and would compare to my modified C-9.

Scopejunkie


Did you grind the lenses, what style (achro, apo) where they, and what were the specifications of the objectives (smoothness, zones, coatings)?


I won't go into the details concerning the three 8" refractors I have built. That's not the reason for this thread. I will say that the lenses were tested before I built scopes around them though.

Scopejunkie
 

#66 doug mc

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Posted 30 November 2013 - 02:04 AM

I thought , what would be better than my c6---- you got it , a c8. So i went and got one. Happy camper. Versatile, comfortable viewing on a stool, no need for hyper expensive eyepieces, yada yada, the list goes on.
 

#67 drago

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Posted 30 November 2013 - 02:25 AM

built quality?

SCT have no chances to good newtonian, imho.


So... What is a good Newtonian?

Strehl doesn't matter if your focuser cannot hold your CCD camera.


i there talking about visual instrument. if we talking about a photographic, then statements is another. large central obstruction and mediocre optics quality there are no problem...
 

#68 kkokkolis

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Posted 30 November 2013 - 02:38 AM

Whose angry? I thought its been fairly good thread. Differing opinions here and there but nothing Id call anger. And the spirit of the OP was tongue n cheek anyway.

Pete


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#69 AlaskaWolf

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Posted 30 November 2013 - 03:46 AM

10-in. F/12.0 Alpha Draconis Apochromatic OTA: $91,280 (used to be a naval gun)
OR
Celestron CGE PRO 1100 EdgeHD : $6,999

Yeah...I think I can deal with the SCT's faults, buy a new F-350, take that vacation to Bora Bora, and get change back ;)

I love refractors...but if I want to see something that big, I'll just head on down to Mobile with Uncle Rod and visit the USS Alabama....
 

#70 Jon Isaacs

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Posted 30 November 2013 - 03:47 AM

My 9.25 SCT kicks my F/5 6" Newts backside.



I imagine it does when it comes to working at high magnifications, it ought to. However there are places a 6 inch F/5 will go that a 9.25 inch F/10 cannot and that's the reason to own both these scopes. One of them is capable of a 3 degree field of view, one of them is capable of a 1 degree field of view..

The right scope for the job at hand is what it all about. There are objects that are best suited for an 80mm F/5 with a 2 inch focuser, there are objects that are best suited for a 635mm aperture.. The California nebula is not much to look at in a 0.7 degree TFoV.

Jon
 

#71 Jon Isaacs

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Posted 30 November 2013 - 03:58 AM

My first real scope was an SCT and I doubt that I will ever be without one. They may not be perfect, but that cannot be beat for size, performance AND price. I have yet to feel the desire to haul around a 6-foot plus tube or a hugely heavy collapsible newt that must be completely disassembled for transport



A data point:

I used to setup my 12.5 inch Tube Dob alongside a variety of guys with 12 inch LX-200s. I could do it in less than a minute, the tube was about 51 inches long... I never did see someone setup a 12 inch LX-200 in less than a minute...

Jon
 

#72 David Knisely

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Posted 30 November 2013 - 04:02 AM

My 9.25 SCT kicks my F/5 6" Newts backside.



I imagine it does when it comes to working at high magnifications, it ought to. However there are places a 6 inch F/5 will go that a 9.25 inch F/10 cannot and that's the reason to own both these scopes. One of them is capable of a 3 degree field of view, one of them is capable of a 1 degree field of view..

The right scope for the job at hand is what it all about. There are objects that are best suited for an 80mm F/5 with a 2 inch focuser, there are objects that are best suited for a 635mm aperture.. The California nebula is not much to look at in a 0.7 degree TFoV.

Jon


Well, the California Nebula is not much to look at in scopes with even a two to 2.5 degree true field of view. To see the whole thing, I need my 100mm f/6 refractor. Still, in my 9.25 inch SCT (59x, 1.12 degree true field of view) using the H-Beta filter at my dark sky site, I can see some of the broad filamentary detail in that nebula by panning around somewhat.

As for the question about why people buy SCT's, the answer is plain: Because they WORK! They may not be exactly the very best in certain areas, but they can be a very effective instrument for the amateur astronomer (I know mine is). Clear skies to you.
 

#73 junomike

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Posted 30 November 2013 - 07:19 AM

SCT ~ Sufficient Compact Telescope.

The "Jack of all trades, master of none."

Mike
 

#74 William Mc

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Posted 30 November 2013 - 08:12 AM

built quality?

SCT have no chances to good newtonian, imho.


So... What is a good Newtonian?

Strehl doesn't matter if your focuser cannot hold your CCD camera.


i there talking about visual instrument. if we talking about a photographic, then statements is another. large central obstruction and mediocre optics quality there are no problem...


Who said this thread was only about visual? I don't care for ugly diffraction spikes, inherent coma which the Edge scopes lack. Limited back focus. You every look through a Newtonian while on a GEM? Was the focuser stuck underneath the scope? And no you can't use a dob mount if you have a observatory with a centrally mounted GEM unless you want to get stuck using only one scope. What's the current most used scope for Planetary imaging? I had to give away my last newtonian as the coating flaked off do to humidity exposure after 7years out in the observatory. That's what happens to unprotected mirrors in this location.

Now all that said, I DO like newtonians,and plan for a big Dob in the future, but if you think that size is the only advantage to a SCT's, well........
 

#75 kansas skies

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Posted 30 November 2013 - 08:37 AM

My first real scope was an SCT and I doubt that I will ever be without one. They may not be perfect, but that cannot be beat for size, performance AND price. I have yet to feel the desire to haul around a 6-foot plus tube or a hugely heavy collapsible newt that must be completely disassembled for transport



A data point:

I used to setup my 12.5 inch Tube Dob alongside a variety of guys with 12 inch LX-200s. I could do it in less than a minute, the tube was about 51 inches long... I never did see someone setup a 12 inch LX-200 in less than a minute...

Jon


Are you not comparing apples to oranges here? I'm assuming that beyond the optics comparison, there's also the alt-az vs equatorial comparison. How much difference in setup time would there be if the mountings were similar?

Bill
 


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