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SC 6 "vs. 5" Mak?

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#26 dsohunter

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Posted 29 August 2012 - 06:48 PM

The c6 is a dog on planets, I had 3 or 4 of them.
Brand new ones and used ones, better on deep sky, pretty good on the moon, but planetary detail banding on jup and sat, not good.


I have found the opposite to be true and have been quite impressed, especially once thermal equilibrium was achieved. I'm sure this is a situation where YMMV.

#27 jrbarnett

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Posted 29 August 2012 - 07:09 PM

Ditto.

The C6s have been the most consistently high quality SCTs I've used from Celestron.

The C6 I have now gives nothing up to the 150mm MCT I had and is within a hair's breadth of the Intes M715 Deluxe I had, across the board (planets, double stars, DSOs, etc.).

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#28 Tank

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Posted 29 August 2012 - 08:02 PM

Bottom line i think is both are good scopes and well i tend to lean towards apeture, but i must say every MAK i have looked thru seems to impress i can say the same with some SCTs.
Cant beat a DOB value wise, to confuse things any intrest in a DOB?? :shocked:

#29 curiosidad

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Posted 30 August 2012 - 04:13 AM

Hello,
How long does it take each of them to get the thermal equilibrium?
Best

#30 ken hubal

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Posted 30 August 2012 - 04:55 PM

I've had the pleasure of viewing through several C6's and was duely unimpressed when compared with the views through my 5 inch MCT and as well as other 5 and 6 inch MCT's. :grin: Every instrument in the comparison had reached thermal equillibrium and was properly collimated. The views in the C6 were typical of SCT's, poor contrast with little to recommend.
The MCT wins, HANDS DOWN!
:grin:

#31 rmollise

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Posted 30 August 2012 - 05:10 PM

Hello
I'm looking at some Cat model that is manageable enough to move with one hand, not too heavy, but with sufficient diameter to enjoy the deep sky objects and planets ..
Perhaps the SC 6 "Mak or 127 ..? Some others?
Thanks


I love my 5-inch MCT but...the SCT, the C6, in addition to adding an inch of aperture--nothing to sneeze at--is at heart a more versatile scope than a long focal lenght MCT. If nothing else, one can use most of the tons of accessories developed for SCTs over the years.

#32 vct123

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Posted 30 August 2012 - 10:04 PM

Thanks Ken , wow, at least one person sees what I see when they look thru a c6, not much to talk about.
Maybe some need to check their eye-glass perscriptions :jump:

#33 BillP

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Posted 03 September 2012 - 09:01 AM

I've had both, and no contest the C6 wins. Extremely bright, not as compact as the 127 but still small, very versatile. My 127 could go no where near as deep as my C6.

#34 vct123

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Posted 03 September 2012 - 10:40 AM

Well, reading the older posts here, the original is comparing a c6 to a 5" mak, but some started comparing the c6 to a 6" mak, so there are two different threads in one.

#35 UnderDriven

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Posted 24 April 2013 - 02:24 PM

Which is better for photography? I suppose that comes down to the flatness of the image plane. As I understand it, the non-EdgeHD SCTs don't have a particularly flat image plane, although the focal reducer helps (but now it's a shorter focal length).

Cheers, Keith

#36 rmollise

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Posted 24 April 2013 - 02:37 PM

Which is better for photography? I suppose that comes down to the flatness of the image plane. As I understand it, the non-EdgeHD SCTs don't have a particularly flat image plane, although the focal reducer helps (but now it's a shorter focal length).

Cheers, Keith


Depends on what sort of photography you fancy. Imaging the deep sky at f/15 or so really ain't much fun... :bawling:

#37 bierbelly

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Posted 24 April 2013 - 02:47 PM

So obviously the consensus here is to go with the AstroPhysics 6"...

#38 Classic8

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Posted 24 April 2013 - 03:23 PM

The SCT may be easier to collimate, but aren't you more likely to have to collimate it, or have to collimate it more often? And when you do collimate it, is it as well collimated as it was when it came from the factory?

#39 rmollise

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Posted 24 April 2013 - 03:31 PM

The SCT may be easier to collimate, but aren't you more likely to have to collimate it, or have to collimate it more often? And when you do collimate it, is it as well collimated as it was when it came from the factory?


Not at all. When collimated properly they hold that collimation very well...as in "months or even years." ;)

#40 UnderDriven

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Posted 24 April 2013 - 03:32 PM

Depends on what sort of photography you fancy.

Sun and Moon...

Cheers, Keith

#41 Classic8

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Posted 24 April 2013 - 04:22 PM

The SCT may be easier to collimate, but aren't you more likely to have to collimate it, or have to collimate it more often? And when you do collimate it, is it as well collimated as it was when it came from the factory?


Not at all. When collimated properly they hold that collimation very well...as in "months or even years." ;)


Just seems like most of the time in SCTs the image seems "soft" and it's hard to believe that so many people have telescopes that are not collimated, if they hold their collimation that well.

#42 KerryR

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Posted 25 April 2013 - 09:03 AM

The SCT may be easier to collimate, but aren't you more likely to have to collimate it, or have to collimate it more often? And when you do collimate it, is it as well collimated as it was when it came from the factory?


Not at all. When collimated properly they hold that collimation very well...as in "months or even years." ;)


Just seems like most of the time in SCTs the image seems "soft" and it's hard to believe that so many people have telescopes that are not collimated, if they hold their collimation that well.


I suspect most folks don't tighten the collimation screws sufficiently. It's also often commented that scopes with Bob's Knobs don't hold collimation as well. It is surmised that this is because sufficient tightness is difficult to achieve with the thumb wheels.

Soft images in SCT's are most often due to a lack of thermal equilibrium in the tube, assuming decent seeing-- the top of the tube looses heat to the sky faster than the lower side, so there's a constant thermal battle inside the tube. Same thing happens in metal tubed Newts. Active venting helps a ton, as does thermal isolation of the interior space.

#43 rmollise

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Posted 25 April 2013 - 09:12 AM

Just seems like most of the time in SCTs the image seems "soft" and it's hard to believe that so many people have telescopes that are not collimated, if they hold their collimation that well.



It may be hard for you to believe, but that is indeed just the way it is. The problem with collimation is that it's often not done or not done correctly. Over the years, people have--for no reason--been AFRAID to collimate their SCTs. :shrug:

If an SCT is correctly collimated it will most assuredly hold that collimation, and its images will most assuredly not be "soft." ;)

#44 Classic8

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Posted 25 April 2013 - 02:59 PM


Just seems like most of the time in SCTs the image seems "soft" and it's hard to believe that so many people have telescopes that are not collimated, if they hold their collimation that well.



It may be hard for you to believe, but that is indeed just the way it is. The problem with collimation is that it's often not done or not done correctly. Over the years, people have--for no reason--been AFRAID to collimate their SCTs. :shrug:

If an SCT is correctly collimated it will most assuredly hold that collimation, and its images will most assuredly not be "soft." ;)


What about the comment above that with Bob's Knobs the collimation screws may not be tightened enough? I had heard that before....also, you can't collimate it until the tube has completely cooled down, correct? It would be easy to think it has cooled down completely when it really hasn't.

#45 rmollise

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Posted 25 April 2013 - 03:49 PM


What about the comment above that with Bob's Knobs the collimation screws may not be tightened enough? I had heard that before....also, you can't collimate it until the tube has completely cooled down, correct? It would be easy to think it has cooled down completely when it really hasn't.


That has not been my experience with Bob's Knobs. Quite the opposite as a matter of fact. And I've had 'em on my Ultima 8 OTA for at least a decade... ;)

#46 hottr6

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Posted 25 April 2013 - 05:45 PM

Cannot comment on SCT vs MCT, but I am with others when they suggest "choose aperture".

My 6" Newt and MCT ALWAYS trump my 5" Newt on every object I have ever compared them with. The difference, e.g., is viewing M13 as a blob, or 100+ resolved stars.

The main reason to consider a 5" over a 6" is that the 6"-class demand more of a mount than the 5"-class. 5" cats will also cool faster than a 6".

#47 DJCalma

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Posted 25 April 2013 - 10:11 PM

My 5" Mak is an awesome scope. Beat a C5 in contrast and resolution, but not sure if the newer C6 would prove much better or not. Also tested my little guy against a couple 4" apos and it was closer than I thought.
I love the package size. My dream scope is a 5" Mak with the light gathering power and resolution of a 24". Yeah, I know all about the laws of physics, but I can dream.






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