Celestron 9.25" EdgeHD OTA

[Stardrifter_WA]

Hi All,

I am looking to replace my Celestron 8" SCT OTA with a Celestron 9.25" EdgeHD OTA. However, I have found little in the way of reviews online.

Has any IIS members compared the EdgeHD and XLT scopes side by side. Is it worth going to the EdgeHD scope?. On paper it appears to be a better system, or at least, should be. But what is the reality?

Thanks Peter

[Wavytone]

Not a significant change.

1. From a C8 you need to step up to a C11 or a 12" of some sort to see a significant benefit. The downside is a huge increase in size & weight.

2. With Celestron/Meade SCT's what you get in the way of optical quality is basically a matter of pure chance - a small few are very good, most are rather ordinary, and there are some real shockers - some C8's cannot resolve Cassini's division on Saturn, for example.

if you are going to splash the cash I'd suggest you consider alternatives, and these depend on what you want to use the scope for.

[Atmos]

For visual the differences aren’t as apparent as with astrophotography. Visually you’ll get a little deeper with that 1.25” extra aperture but photographically the Edge is definitely superior.

I’ve personally never used either of them but the Edge series is far better corrected than a standard SCT when used for photography.

[casstony]

If you use the scope for lower power viewing the Edge has a much better outer field than a standard SCT in the 8" and 11" sizes. The standard C9.25 isn't as badly aberrated so there isn't as much to gain going to the 9.25 edge.

You need to jump to 11" to see a big difference in brightness, but I'd be looking for a used 11" Edge to save a couple thousand dollars.

[Stardrifter_WA]

The 9.25" is pretty much the limit, in size and weight, as this will be mounted on a side by side plate with my William Optics 110FLT, in my observatory. My deforked 8" is okay, and I am only considering going to the 9.25" as I am considering the EdgeHD. Since I have fixed my fork mount I want to refork my 8" so that I can take that out to a dark sky site, particularly since my WO110FLT is now permanently mounted.

The 11" would be preferable, but that would mean a change in size and weight and a change in mount, for that matter, something I am unable to afford to do any time soon, if at all. I do have a 16" for aperture.

Given the above, my query is simply the difference between the 9.25" EdgeHD and XLT. I know, on paper, the difference, but I also know reality can be different again, thus I am looking to hear from anyone who has compared them. The price difference is significant. I am surprised there are a lack of reviews on the 9.25" EdgeHD. Maybe that is because most people go to the 11".

Cheers Peter

[casstony]

Hi Peter, for visual in the 9.25 size I’d probably stick with the standard SCT. I’ve owned both versions and the C9.25 isn’t so bad at the edge of field.

In SCT sizes other than 9.25 I find the outer field horribly bad.

[Zuts]

Well I'm happy with my 9.25 edge. Obviously if you are asking about aperture then sure 11 inch is brighter. However I had an 11 inch circa 2000 sct and Was unhappy with the stars. On the edge they appeared pinpoint out to the edge.

If you are looking at extended objects then there is not much difference. For photography it's great. It has mirror locks, is light and after taking off the corrector and secondary I found the mechanical design far superior. No cork/ paper shims etc, clear registration marks and so on.

You will find accessories more expensive though. No more cheap f6.3 reducer, the edge hd one is around 500 dollars.

As with anything you get what you pay for; and you need to be happy with it. When it's collimated I get pinpoint stars to the edge.

My 2 cents.
Paul

[Stardrifter_WA]

Thanks for the input, something to mull over.

Cheers Peter

[Stardrifter_WA]

Hi Paul,

That is the other side of the coin, mechanical quality. As a machinist I appreciate great build quality.

Peter