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Upgrade to 9.25 SCT, what to expect

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#1 drewh111

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Posted 06 April 2019 - 06:20 PM

I have been enjoying my old Meade 125 here in New Mexico .I am right in Santa Fe NMNso have moderate light pollution but enjoy the clear cold skies at night. I seem to be limited to objects at about 6.9 magnitude. For instance I can see Bodes nebula as a faint cloud on a good night.  Wondering how much more I'll be able to see with the 9.25. I am pretty happy with me eyepieces especially the Orion. It seems to magnify faint DSOs better than the ES .


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#2 Tyson M

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Posted 06 April 2019 - 07:23 PM

A 9.25 will show considerable more detail on DSO's, and make smaller objects like planetary nebula much more enjoyable to view.


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#3 stoest

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Posted 06 April 2019 - 08:08 PM

In my 9.25 SCT from my suburban back yard I can see the large dark lane in M82.  From a dark site there are variations in density through almost the entire object.  I think you'll find a significant difference especially if you can get to a little darker skies.



#4 drewh111

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Posted 06 April 2019 - 10:41 PM

Thanks for the replies, very helpful. I really want to pull the trigger on the 9.25 now.

 

Mariner, do you find the 6.7 to be as high a magnification as you would use? 

 

thanks,

 

drew.



#5 tross

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Posted 07 April 2019 - 12:18 AM

The 9.25 is a very good SCT , not too heavy. 

You didn't specify which version you are looking at or the mount.

 

Mine is the older USA version and I have several good eyepieces as well as focal reducers, depending on what I'm interested in viewing.

I use all 2inch and not 1.25 

 

carl


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#6 Traveler

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Posted 07 April 2019 - 01:44 AM

Long time thought about a C9.25 or a C8. Decided to own a C8 because of the considerble smaller footprint (more transportable) and with enough punch on DSO when comparing with a C9.25. The DSO penetration difference between a C8 and a C9.25 is not big enough to overcome the C9.25 bigger footprint.To make really a step forward consider a C11 in stead. Not that much bigger then the C9.25. Much depends on your used mount however.

Besides that, i am not from the school who thinks the C9.25 is the best SCT because of the optical design...but that is another story...



#7 gnowellsct

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Posted 07 April 2019 - 08:01 AM

Mariner, do you find the 6.7 to be as high a magnification as you would use?

thanks,

drew.

At f/10 your theoretical max is a 5 mm ocular or 2x per mm or 470x.

Other than that your preferred magnification is up to you. With a 2.5 mm you can push to 940x (which will be disappointing) or observe with a lower practical ceiling given the usual seeing. A 7 XW is an excellent ocular and at 335x an excellent and practical upper limit f or wonderful nights. Cruising speed would be 10mm and higher focal length (lower magnification) oculars.

At star parties I often demonstrate crazy high magnifications so that people "get it" about dimming out and empty magnification.

Edited by gnowellsct, 07 April 2019 - 08:05 AM.

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#8 Astrojedi

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Posted 08 April 2019 - 09:35 AM

The C9.25 XLT I have is a superb scope. They can really take magnification well. I have pushed it to 400-500x on planets in good seeing. For bright planetaries if seeing permits I push it to 700x. 

 

I have significant experience with C8 and C9.25 both XLT and Edge versions. The biggest differences between a C8 and a C9.25 are a more flatter field, better resolution and the ability to push the magnification in the 9.25. You will not notice much difference in brightness or magnitude depth.

 

The reason I mention C8 vs C9.25 is that you should also include the C8 in your decision tree. Both the C8 and C9.25 will provide an amazing increase in light grasp over the 125. With the C8 being about 6lb lighter.


Edited by Astrojedi, 08 April 2019 - 09:48 AM.

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#9 Astrojedi

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Posted 08 April 2019 - 09:41 AM

But if you go with a C9.25 it is still a light OTA just 18.5lb. Works superbly on my M2C (although for high magnification work > 200x I prefer a tracking mount)

 

65502057-D2FC-4B75-B0B0-00AC560A0EF9.jpeg

 

C2E0EA76-8929-4AFF-AC8E-5C3100E820A6.jpeg

 

 


Edited by Astrojedi, 08 April 2019 - 09:48 AM.

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#10 carolinaskies

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Posted 08 April 2019 - 09:42 AM

The 9.25 will be a substantial increase in resolution over the 125. 

You'll find the field is about 20% smaller for a given eyepiece because of the longer focal length of the 9.25(2350 vs 1900)  though you could use a .63x focal reducer even for visual which would utilize the light gathering of the 9.25 to still appear brighter than the 125. 

Your visual magnitude should increase to about 9-12 depending on your local darkness level.  Theoretically you should see dimmer but factors often limit this number.  Count your blessings if you can approach the optimal skies.  

The weight difference between the 125 and the 9.25 is quite a bit, visually your mount will 'handle' the 9.25 reasonably in average conditions.  


 


Edited by carolinaskies, 08 April 2019 - 09:44 AM.


#11 delgado39

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Posted 08 April 2019 - 11:26 AM

At f/10 your theoretical max is a 5 mm ocular or 2x per mm or 470x.

Other than that your preferred magnification is up to you. With a 2.5 mm you can push to 940x (which will be disappointing) or observe with a lower practical ceiling given the usual seeing. A 7 XW is an excellent ocular and at 335x an excellent and practical upper limit f or wonderful nights. Cruising speed would be 10mm and higher focal length (lower magnification) oculars.

At star parties I often demonstrate crazy high magnifications so that people "get it" about dimming out and empty magnification.

Good advice!!  I found a 7mm and 10mm to be my cruising speed on average to above average nights.  Rarely going beyond that range unless its an exceptional night.  With big aperture, objects can get soft around the edges quickly at high magnification.


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#12 Astrojedi

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Posted 08 April 2019 - 12:15 PM

Good advice!!  I found a 7mm and 10mm to be my cruising speed on average to above average nights.  Rarely going beyond that range unless its an exceptional night.  With big aperture, objects can get soft around the edges quickly at high magnification.

Depends where you live. If you are closer to the CA coast you will have much better seeing due to the laminar flow. 200x-250x is an average night for me. On good nights 400-500x is not out of the question.



#13 gfstallin

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Posted 10 April 2019 - 10:58 PM

I would have advised against using a CEM25p with a C9.25, but it appears there are some happy users of the combination out there, along with some deep sky images (seriously) as some proof in the pudding. Call me impressed. 

 

I remember moving up from a 127mm Apex Mak to a C8. For me the difference was substantial and immediately apparent. The difference between a C9.25 and C8 is more academic. I notice it in planetary and lunar imaging. In my light-polluted skies, I haven't noticed any difference between the two for deep sky. Under high-magnification, planets are brighter and the image in the C9.25 is more pleasing (hard to put my finger on why that is...could just be perception/expectations), but deep sky fuzzy objects are still fuzzy in the C9.25 compared to the C8. No surprises there, really, but worth noting. I certainly doubt there would be the same WOW factor I had between the C8 and 127 Mak. All of this to say, either with a C8 or C9.25, over your 125 Mak the difference will be substantial and immediately obvious - not incremental. Objects you viewed with the Mak will be brighter at similar magnification, and the difference in lunar resolution (especially) is rather striking. I think you'd be happy with either one. As others noted, the C9.25 is certainly portable, though the C8 is in a different class of portability - more similar to your 125 IMHO than it is to a C9.25 in terms of bulk. Btw, if you like your 125, keep it! Especially if you get a C9.25 over a C8. I sold my very good 127, and have regretted ever since (see my signature). There is somethimg to be said about an OTA that fits in a glorified lunchbox. 

 

George


Edited by gfstallin, 10 April 2019 - 11:01 PM.


#14 MCinAZ

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Posted 11 April 2019 - 12:36 AM

  I bought a C9 1/4 XLT toward the end of US production, as I determined that it was probably the largest aperture I could put on my GM-8. While my interest was increasing limiting magnitude for timing occultations, I have made many observations with the SCT since acquiring it. Compared to my 135 mm Maksutov, it will show stars at least a full magnitude fainter and, on rare nights of exceptional seeing in the desert provided very impressive planetary views. I think you would find the step up to be considerable.

 

  I had a C11 for a while. Star images in the C9 1/4 were always better, and there were several times when I had both telescopes set up simultaneously to make the comparison. That may not necessarily be true if you compare current production telescopes, of course. I put the C11 on the GM-8 a couple of times (it normally rode on a G-11 in an observatory, while the GM-8 goes on the road). Whereas the C9 1/4 really doesn't tax that mount (for visual observing, at least), the C11 was clearly beyond its useful range. If, as suggested above, you opt for a C11, be sure you have a mount capable of carrying it.



#15 drewh111

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Posted 20 April 2019 - 05:56 PM

The C9.25 XLT I have is a superb scope. They can really take magnification well. I have pushed it to 400-500x on planets in good seeing. For bright planetaries if seeing permits I push it to 700x. 

 

I have significant experience with C8 and C9.25 both XLT and Edge versions. The biggest differences between a C8 and a C9.25 are a more flatter field, better resolution and the ability to push the magnification in the 9.25. You will not notice much difference in brightness or magnitude depth.

 

The reason I mention C8 vs C9.25 is that you should also include the C8 in your decision tree. Both the C8 and C9.25 will provide an amazing increase in light grasp over the 125. With the C8 being about 6lb lighter.

thanks for this post (and all the others). I am leaning back towards the C8. We have been travelling around New Mexico to some fabulous dark sky sites. I took the 125 up and set up with the CEMP25. It was all manageable but definitely alot of gear to load up and set up. I think I want to optimize for travelling and weight. Not to mention, I am on a budget.

 

As an aside, we went up to Choco Canyon and spent two nights. It is reputed to be a great dark sky site.  They have a small observatory with a 25" Dob and a few other scopes. There was a gorgeous full moon that completely obliterated everything but the brightest of stars. Oh well. 



#16 drewh111

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Posted 21 April 2019 - 02:13 PM

Pulled the trigger on a new 8se SCT

ota. One of the online stores had what seemed to be a good deal . Thanks again for all the helpful input .


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#17 Stargazer3236

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Posted 22 April 2019 - 10:02 PM

You will be very happy with the Nexstar 8SE. Besides the OTA, the mount works rather well, but you must be careful of your approach to aligning stars. I think the current option is up and to the right, when aligning your stars in Alt-Az mode. It is whatever the default option is when you first power up the scope.

 

You can also detach the OTA and place it on another mount. I do that with my Nexstar 8SE and place it on my iOptron ZEQ25. I will also start using my Nexstar 6SE OTA on the iOptron too, for imaging the planets. What you might want to try is buying the wedge ($299) for the Nexstar 6/8SE mounts and try imaging in EQ mode without worrying about Meridian flip.

 

Buy yourself a nice TalentCell 8300mah portable battery. It will last 2-3 sessions of 6 hours each before needing re-charge. Also, put 8 AA batteries in the battery chamber. If your portable battery ever disconnects, the on board batteries will keep the scope powered until you plug the cable back in and it won't require you to re-align the scope.

 

Buy a Rigel Quik Finder or a Telrad, the red dot pointer that comes with the scope absolutely blows chunks. Also buy a Heated Dew Shield, your corrector will fog up on humid nights. A 2" diagonal will work with this aperture.


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#18 drewh111

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Posted 23 April 2019 - 08:18 PM

Thanks David . I have a Cem25p and bought the 8se ota . Getting it Friday and should have clear skies . 



#19 AxelB

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Posted 23 April 2019 - 10:29 PM

Congratulations on the 8se. 8" is quite nice and still portable. An alt-az mount is also faster to setup than an equatorial. Let us know about your first light!

#20 drewh111

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Posted 28 April 2019 - 11:27 AM

I am very glad I settled on the 8". It surprised me how much bigger it is than my ETX 125 but still very light and easy to mount.

 

I set it up early and impatiently waited for the sun to set. Just as Polaris was making an appearance, a huge cloud moved through. In the meantime, I found Arcturus and checked collimation. From what my inexperienced eye could tell, it looked perfect! So finally I was able to locate Polaris and do a Polestar alignment. I then did a three star alignment using Arcturus, Pollux, and Spica, then the fun began. 

 

Conditions were very average with some clouds still around. The sky did clear as it got later but an average night at best. I first found M3 and was able to see individual stars with the Megaview 7mm. Not a definite wow yet. I went through a long list of objects: m67, m44, m5, m53, m48. I spent time with objects near the Zenith then move on to objects lower on the horizon. M 81 was great but the wow moment came with M82. I could see the cigar shape and nearby stars pretty destinctly. I then looked for fainter objects and was able to see m51, m106, m94, and finally m100!

 

So a pretty good start with the new scope on an average night. Next week I plan on lugging out to a dark sky site nearby and fortunately I don't have to go far from Santa Fe. 

 

Thanks again for all the input and advice, it was very helpful.  


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#21 Astrojedi

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Posted 01 May 2019 - 11:02 PM

thanks for this post (and all the others). I am leaning back towards the C8. We have been travelling around New Mexico to some fabulous dark sky sites. I took the 125 up and set up with the CEMP25. It was all manageable but definitely alot of gear to load up and set up. I think I want to optimize for travelling and weight. Not to mention, I am on a budget.

 

As an aside, we went up to Choco Canyon and spent two nights. It is reputed to be a great dark sky site.  They have a small observatory with a 25" Dob and a few other scopes. There was a gorgeous full moon that completely obliterated everything but the brightest of stars. Oh well. 

I lived in NM for a couple of years many moons ago. Loved the place. 

 

Just wait till you take the C8 to a truly dark site. It will blow you away. Many scopes have come and gone over the past 2+ decades including some very premium ones but I have always had a C8. There is no scope of any design as powerful, versatile and portable as a C8.


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#22 Stargazer3236

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Posted 02 May 2019 - 07:19 AM

Either the Celestron or Meade 8 inch SCT's are truly wonderful scope to use. Very versatile from F/2 up to F/30. Just make sure you have plenty of focal reducer/correctors and barlows to achieve that task. One night you could be imaging the planets with a barlow and in an hour or so, switch to a reducer and capture wide field shots of DSO's and then go back to planetary imaging with a barlow. The weight and compactness of an SCT is just a perfect match of portability and aperture. It is the median amount between a small 4" scope and a larger 12" scope. Like they say, the best scope to use, is the one you use the most!


Edited by Stargazer3236, 02 May 2019 - 07:20 AM.

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#23 drewh111

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Posted 04 May 2019 - 02:27 PM

I lived in NM for a couple of years many moons ago. Loved the place. 

 

Just wait till you take the C8 to a truly dark site. It will blow you away. Many scopes have come and gone over the past 2+ decades including some very premium ones but I have always had a C8. There is no scope of any design as powerful, versatile and portable as a C8.

Yes, I cant wait. Going to try going up into the Pecos Wilderness next weekend, though there have been a lot of storms going through. I also have heard that City of Rocks State Park is an awesome location.



#24 gnowellsct

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Posted 05 May 2019 - 04:34 PM

 

Just wait till you take the C8 to a truly dark site. It will blow you away. Many scopes have come and gone over the past 2+ decades including some very premium ones but I have always had a C8. There is no scope of any design as powerful, versatile and portable as a C8.

 

It certainly packs a punch, I like mine very much.  Overall the 130 GT is a much better scope 1 v 1.  Put a 92 mm or an 81mm on the c8 and the advantage tilts to the dynamic duo.   But the GT has superb "handling" and I kinda wish the c8 were better than it is in terms of focus at small exit pupils.  The weak point of these SCTs is the focuser.

 

Greg N




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