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Celestron 8 edge HD or C 9.25 upgrading from 6SE

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#1 mskillen

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Posted 13 July 2013 - 05:06 PM

Hi Folks,

I know this subject has been beat to death lol, but I'm curious.

So what I currently have is the Nexstar 6SE, I have decided to upgrade to a larger scope.

I have purchased and received my new mount, it is the Celestron advanced VX Equatorial Mount

I have been using the 6"SCT from the SE on this mount and I have been really pleased with its performance.

But the reason I bought the VX mount, was because I was going to get a larger SCT.

The question I have is which one will be the better value for me, this is kind of budget driven as well.

The 8"Edge HD is roughly 1200.00 and the C9.25 is also in that price range, so I have a dilemma, I'm not doing AP at least not now, but I do allot of visual.

So Stepping up from a 6" and wanting to stay in that budget, is the 9.25 the better deal?
I'm sure the 9.25 will be a huge difference over the 6"
and I feel that I would be happy with that.

The 8"edge has nice features but they are mostly for AP and from what I have read its not something that you would notice, but the camera does over a regular C8

This will probably be the last setup I buy for many years I just want the best bang for the buck.

Not having any experience with these scopes doesn't help my decision either, any thoughts, pros or cons, of each scope?

What the better deal?

I hope that this made sense, just kinda of torn on making my final decision.

Thanks
Mark

#2 Eddgie

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Posted 13 July 2013 - 05:34 PM

I think that aperture is your friend, and I usually advocate goings as large as you can.

If you see yourself using Ethos or similar 100 degree AFOV eyepieces (or even Naglers) a lot, then the EdgeHD 8" may be more desirable, but if you are content with 68 degree and narrower eyepieces, then by all means, get a C9.

But you will get to many different opinions on this. I have owned C5, C8, EdgeHD 8", C9.25, C11, C14, a bunch of small APOs, a big APO, MNs, Newts, and everything else.

And my bottom line recommendation is almost always the same..

Biggger IS Better. The bigger you go, the more you get to see. This is the most fundamental lesson in the game.

#3 jrbarnett

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Posted 13 July 2013 - 05:54 PM

That is an excellent question.

The big benefit of the Edge system is suppression of field curvature. By flattening the field, stars are in focus from center to edge. Hence the name. In a standard SCT when stars on axis are focused, stars off axis are bloated, de focused blobs.

However, if you're young, your eyes will accommodate defocus off axis as you pan around the field. For younger visual SCT users, field curvature isn't such a big deal. Also, the 9.25s have slower primaries and less native field curvature tha all the rest which have faster primaries. That means of all the standards SCTs, the 9.25s need Edge "magic" the least.

Ergo, if your eyes have decent accommodation, you are a visual observer, and you have a CGEM or Atlas capacity mount, the standard 9.25 might be a better choice for you. More aperture, deeper limiting magnitude, better resolution.

On the other hand, if you're a little older or don't have a beefy mount, the C8 Edge might be the better bet. Either will be substantially better than the C6.

I'm struggling with the same question myself at the moment.

- Jim

#4 dr.who

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Posted 13 July 2013 - 06:12 PM

FWIW the AVX will handle up to an 11 edge with no problem for visual so I would suggest the 9 1/4" as Ed says aperture is your friend. Though if you have an extra grand go to the 11" ;)

#5 Eddgie

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Posted 13 July 2013 - 09:15 PM

Yes, I agree, if there is budget, get a C11.

A used one can be had for not much more than new EdgeHD 8".

I progressed up through the SCT sizes, and my biggest regret in all of the astronomy purchases I have ever made was that I did not start with a C14.

I believe the OP may have had a CPC 1100??????

#6 orion61

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Posted 15 July 2013 - 09:28 AM

The 11 starts to get on the heavy side. the best scopes are the most used ones. I have scopes of all sized and types. my most used scope is still my fork mounted C8.
The larger scopes tend to to get the "why bother" syndrome
after the inital excitement weard down. Either that or they tend to get left outside.
There is quite a bit of bulk difference in that 1.5 inches.
One thing not answered is the difference the larger scope is affected more by local seeing conditions.
But since you have the C6, I would go the 9.25 and the F6,3
FF/FR.
In the future, if you have room, a larger Dob.

#7 WesC

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Posted 15 July 2013 - 01:10 PM

I'm dubious of a C11 on the VX mount. I have an Edge 11 on a CGEM and its pushing it. I would get the Edge 9.25.

#8 mskillen

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Posted 15 July 2013 - 04:43 PM

Well I know I cant swing the 9.25 edge right now, but the difference in price between the 8" edge or the standard c9.25 is pretty close.

From what I have been reading and following Jim around in all these threads lol, I have a feeling that the standard 9.25 will suit me.
Its the most I can afford at the moment, and the largest aperture in that price range.
And from what I gather it is a nice scope, prior to all the edge scopes hitting the market it seemed like a popular choice.

I already have all the Baader Hyperon eyepieces so I think I'll be happy with it.
I was just curious if the 8" edge was going to be something that really stood out as a better option.
But if your not into AP, I'm not sure if it would really be significant or noticeable.

So definitely leaning to the 9.25, and I think for the AVX mount its not going to overload it and it can still handle a larger finder scope etc...

Mark

#9 Dunkstar

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Posted 15 July 2013 - 10:14 PM

Without standing them side by side and comparing it's hard to tell which stands out most for you but if you stick with your Hyperion eyepieces the standard SCT will do just fine and aperture is king. The 8 is still a good upgrade in light grasp from the 6 though, and if you were interested in wider apparent FOV eyepieces (Nagler, Ethos, etc) then the Edge HD models would be the more obvious choice.

The Edge HD models also have vents to aid cooling which is also useful for visual although there have been some reports of regular XLT models having those also.

#10 REC

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Posted 16 July 2013 - 03:03 PM

FYI...take a look at Todd Gross views on the 9.25"....good read. Have fun with what ever you get:)

#11 Seiko4169

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Posted 17 July 2013 - 03:27 PM

I just went through the same process and opted for a regular 9.25 XLT for visual use as the 11" would have been too big for my mount and the Edge 9.25 far too expensive for just vents and mirror locks. Flat fields might be noticeable for some but in my Edge 8 and CPC 1100 deluxe I was hard pressed to see the difference. I don't doubt for one minute the differences are there and that for seasoned astronomers the effects of field curvature are a pain but for me and my eyepiece collection at the time I couldn't see anything.

By far the most important thing is to get a good sample. A good one comes to life as everything kind of just sparkles. An average one just doesn't seem to have that 'zing"'

I hate the *BLEEP* shoot when getting one though. There is 100% a market for Celestron to cream off their best to those that care and charge extra,

#12 GeneT

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Posted 17 July 2013 - 03:51 PM

This would be a tough dilemma for me. You state that this will probably be the last telescope you buy for many years. Given that, could you swing the 9.25 Edge? My son and I had a similar discussion a few years ago. For budgetary reasons, he was going to buy a new 37 inch HD television. He had room on the wall he was going to hang it for a 55 inch. I asked, 'what is the difference in price between a 37 and 50 incher?' He said, about $500. I said, that TV will probably last you between 5 and 10 years. That's only about $100 a year for something that will give you and your family much more enjoyment. He bought the 50 inch HD TV. My grandkids were delighted. My daughter wasn't very happy with me, though. :grin:

#13 mskillen

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Posted 17 July 2013 - 05:00 PM

Well I would love to do the 9.25 Edge, but it just seems like 1000.00 more for some features that I don't know If I would really gain any value from at this time.

So that's kind of where I am at, that's why I compared the standard 9.25 to the 8 Edge.

If the optics were dramatically different over a standard scope I would chose the 8 edge instead of the 9.25, but if there really is nothing gained whats the point.

The 6SE that I have is great but its just a tease, good enough to find things, but not enough light to bring them into detail.
The 8" is 78% more light than the 6" and the 9.25 is something like 111 more times.
I think the edge system is for photography for the most part.

So I understand the theory with the TV's lol, but what am I really paying for in the long run.

Thanks
Mark

#14 Reid W

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Posted 17 July 2013 - 10:36 PM

Just came in from viewing with my standard 9.25 with an ES 28mm 68' eyepiece. It is hard for me to see any edge of field issues. That said, I've looked thru a std. 8", and edge of field was bad.

#15 jimb1001

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Posted 18 July 2013 - 12:54 AM

Here's something to consider.

Get a standard 8" used, there are plenty of good ones around.

Add to that a Mallincam, or equivalent.

You will "see" more dsos with that combination than any of the other scopes mentioned with an eyepiece, and the scope will be fine for planets and lunar with an eyepiece.

#16 Dunkstar

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Posted 18 July 2013 - 04:45 AM

With the size of the central obstruction being larger in the 6" it's more like 90% more light gathering with the 8".

#17 Dunkstar

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Posted 18 July 2013 - 04:47 AM

Using 68 degree eyepieces with a 925 is not surprising you don't see anything. Try a Nagler or Ethos :shocked:

#18 ensign

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Posted 18 July 2013 - 10:32 AM

I'm coming at this from the opposite direction. I recently sold a standard C8 (with the XLT coatings) and traded up to a 9.25 Edge HD. I found the views in the standard 8 to be less than sharp. Maybe the issue is my old eyes being unable to adapt to field curvature.

I even went so far as to add a .63 reducer/corrector to the C8 and this improved things somewhat. But the 9.25 Edge provides much sharper views. I'm seeing somewhat more detail in objects than I did with the standard 8 and while aperture is part of this, I think the corrected optics are more of a factor.

Long story short, if it were me, I'd go for the 8" Edge.

#19 Eddgie

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Posted 18 July 2013 - 01:59 PM

Just came in from viewing with my standard 9.25 with an ES 28mm 68' eyepiece. It is hard for me to see any edge of field issues.



This has been my position. If you use Panoptics or ES 68s, Or hyperions (except for the 24mm which is not quite as well corrected at the edge as the others), there is little benefit in having the EdgeHD optics.

When using Naglers or Ethos though, the off axis performance of the standard SCT starts to burn though.

I am an advocate of using 68 degree eyepeices in SCTs anyway because the lower powers for a given true field size generally keep the stars that are bloated from seeing small enough that they still appear sharp.

I think that the whole "refractors are sharper" is often an artifact of using Naglers in SCTs. When used with Panoptics stars across the field generally always appear sharper because the magnification is low enough that the blurred Airy Disk is hard to resolve, so you still see points.

I think if the OP has Hyperions and likes them, and doesn't see $500 and $600 eyepeices in his future, the C9 is a better choice.

#20 Reid W

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Posted 18 July 2013 - 05:08 PM

Ed, you just nailed the argument. I have not used any eyepieces greater than 68'. Our Shreveport group is getting together this weekend, and I'll find someone with an ES 100 and see how it performs in the std. 9.25. It might open Pandora's Box. Great.

#21 Dunkstar

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Posted 18 July 2013 - 06:36 PM

It was the coma that pushed me over the Edge...once I'd seen it, I couldn't un-see it :(

A very nice little Edge the 8 is too :cool:

#22 vct123

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Posted 18 July 2013 - 07:30 PM

I have owned both and currently have a c9.25xlt and an older c8. I am using 60-65 degree eyepieces: Radians, Pentax xl, Vixen LVw's and the views are sharp. I prefer the c9.25 xlt over a c8hd and also feel the c9.25 is one of the best sct's for planets.

#23 mskillen

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Posted 18 July 2013 - 08:02 PM

I am most interested in DSO's, galaxys etc, how does the 8" do on these?

For example In the 6" I can see M31, But my feelings are that if I had more light it would stand out allot more than it does, and with better contrast.

I have never looked through a larger telescope than my 6",
My fear would be that I would sell myself short.

I kinda had this feeling when I got the 6" and wished I would have got the 8" instead.

With the 8 HD and the standard 9.25 being so close in price, I don't want to have that feeling again lol.

Kind of like I shorted myself, so if the 8HD was really optically and functionally better than the standard 9.25, I would get it.

But since aperture rules and I have a rough price point that I am willing to spend, Its a tough choice for me to make.

As stated earlier they are both superior to the 6", I have not had any coma issues with the 6" unless I pushed the magnification then it becomes more noticeable.
My 13mm and my 17mm eyepieces get the most use.

I think it might have been a little easier if this had been an standard 8" vs the 8"edge, because for the price difference, it would have been easily worth the value and the benefit.

But since this is the 8"HD edge vs a standard C9.25 it makes it a little more difficult. Plus the 9.25HD edge is almost a grand more, I don't want to spend that much.

As far as eyepieces go I love the Baaders, they are a Hugh upgrade to anything I have ever looked through before.

The 68 FOV is pretty awesome to me.
To use 100Deg fov don't you have to go up to 2" eyepieces?
I don't know if that's correct, I thought you were limited by the baffle tube in the scope as to how far a fov you actually got.
So unless you actually have a scope like the 11 to 14" that will take a 2" you don't get the true benefit from these eyepieces is that correct?

Anyway 8"edge better Mirrors, flatter field, more light than the 6" and allot of nice features not found on the Standard SCT's, Made for people that do AP work

And the Standard C9.25 larger aperture more light, big upgrade from the 6" I have.

Both are basically the same price point. 1300.00
Both will work with My AVX mount and my Baader eye pieces.

Is it worth going down a aperture size for the extra features of the 8"Edge?
Or is aperture the way to go? I'm sure the 9.25 standard scope is still a nice piece of equipment.



I would like to thank everyone for there responses so far, I really appreciate it.

Thanks
Mark

#24 Sorny

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Posted 18 July 2013 - 08:32 PM

If you are happy with 70 degree class eyepieces, and not into imaging, then the choice is simple; bigger is better.

I upgraded from a 5" to an 11". If Celestron made a CPC1400, I'd have gone with that instead of my CPC1100; I'm a big fan of fork mounts, even if they are nowhere near as versatile as a GEM.

#25 Dunkstar

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Posted 18 July 2013 - 11:24 PM

The baffle tube prevents the scope from giving a wider field of view on the 6SE... but the bigger scopes have larger diameter baffle tubes. Even with the 8 the baffle tube is large enough for longer focal length 2" eyepieces to be used with good results and with the 9.25 there is practically no restriction.

The C9.25 with a 40mm or so 68-70 degree 2" eyepiece would show about the same amount of sky that your 6SE can, but it has a focal length over 50% longer.

If you want to collect as much light as possible, the 9.25 wins but if you stick to 1.25" eyepieces you're only viewing part of what your scope is collecting. The same is true with the 8 and 1.25" eyepieces.

M31 is a difficult object to view in SCTs because you can only really see the core...it is about 3 degrees from end to end, or 6x the width of the full Moon! You need a wide field of view from a small refractor or a pair of binoculars to see all of M31 at once.






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