Anyone using a Celestron Edge Scope?

[Tim99]

I have been enjoying my 80mm Triplet Refractor but now i would like something bigger for both Planetary and DSO.  I have done a lot of reading and wonder if the Celestron Edge SCT is what I want?  The Edge 9.25 telescope on a CGEM mount seems like a manageable system to load in my car to take to my "dark spot."  The price seems reasonable for a decent Astrograph quality instrument.  Any opinions on this set-up?

[knobby]

The 9.25 will be excellent on planets but very slow and hard to guide on DSO objects ... Even with the hideously priced reducer.

Maybe try the ' non edge ' 9.25 dual mounted with your existing triplet for DSO work and the 9.25 for planets ... (Sometimes the whacky ideas work)

[Geordie mc]

I have the 8 inch Edge and I love it for Lunar and planetary work. I looked at the 9.25, but was told there was no dedicated reducer available for it and the 11 was too expensive for me. Seemed strange that the 8 and 11 have reducers and the 9.25 doesn't? Maybe I was misinformed, but I spoke to a few people at this year's Astrofest and they all said there wasn't a reducer available specifically for the 9.25 edge. I was amazed by the 8. The views of Jupiter are fabulous. Only thing I would criticise is the focusser. I intend to upgrade this to a moonlight or feather touch as soon as funds allow.

[Tim99]

Thanks for the comments .  I also heard that there was no reducer yet for the 9.25 but that one was in the works.  Seems like the people who have the money to buy the Edge system really like them.  I haven't ready any bad comments anyway.  Interesting that the focuser is not up to par.  Time will tell and as you say, I can always replace it with a better one.  The 9.25 comes with a 2" focuser .... maybe that will be more substantial.

[Geordie mc]

It's substantial enough, but not very sensitive so getting good focus when imaging is tricky. You can lock the mirror after achieving focus to avoid mirror flop which is s big plus.

[Tim99]

 Just found a reducer for the  9.25 Edge.  The HyperStar C9.25 lens converts a Celestron Edge HD 9.25" SCT from f/10 to f/2.3.   The 9.25" SCT uses a slightly different optical configuration, in order to produce a flatter field of view and have a smaller central obstruction. This means it uses a slower primary mirror (f/2.3 versus the f/2 mirror in other SCTs). This means the HyperStar has to be slightly slower to retain its excellent optical performance. The difference between f/2.3 and f/2 is negligible. So, I guess those of us with the 9.25 can take advantage of this option if we want to bend over for the $950.00 price for the Hyperstar lens.  Holy [removed word]!  

[Grotemobile]

If your going to do planetary  Imaging ,

go for the CPC 800 Edge.Best

I have ever had.So easy to set up

&  use.Sold the C11 to fund this.

This was taken with this scope,

&  a  IMG 132E   camera.Shows

what it can do.

Steve.

[ollypenrice]

 Just found a reducer for the  9.25 Edge.  The HyperStar C9.25 lens converts a Celestron Edge HD 9.25" SCT from f/10 to f/2.3.   The 9.25" SCT uses a slightly different optical configuration, in order to produce a flatter field of view and have a smaller central obstruction. This means it uses a slower primary mirror (f/2.3 versus the f/2 mirror in other SCTs). This means the HyperStar has to be slightly slower to retain its excellent optical performance. The difference between f/2.3 and f/2 is negligible. So, I guess those of us with the 9.25 can take advantage of this option if we want to bend over for the $950.00 price for the Hyperstar lens.  Holy [removed word]!  

I wouldn't really call this a reducer. It totally changes the scope and brings it down to small refractor focal length but with faster F ratio (and a lot of complications arising from ultra fast optics.)

Thinking now about deep sky, what camera are you aiming to use? I ask because the pixel size starts to become very important once your focal length goes up. This calculator will allow you to see how many arcsecs per pixel a given system will acheive.  http://www.12dstring.me.uk/fov.htm  If you go below 1" p/p you are going to need both very good seeing and very good autoguiding. Without them the theoretical resolution of the bigger scope will be blurred out, leaving no advantage over a shorter FL scope  working with the same camera - and the shorter FL would give you a wider field of view.

I feel the budget mounts (HEQ5/NEQ6 etc) have left their comfort zones after about a metre of FL. They can and do go longer but the longer you go the more fine tuning you'll need.

It's important to be aware of this.

Olly

[Geordie mc]

The Hyperstar system has a lot of issues, not least achieving focus at f2.3. It requires very accurate setting up and isn't an easy swap out. I've seen some great images with it but mainly from people with expensive mounts and permanent set ups. I think you get about 650mm focal length. I'd rather go for a refractor than have the hassle of using Hyperstar, but if anyone is using it and finds it great I'd love to hear your opinions as I have no personal experience to draw on and have considered trying it. It's just such a lot of money to gamble.

[Tim99]

Ahhhhhh, I'm starting to get the picture!  LOL.  The Hyperstar aspect may not ever be considered now that I am understanding the theory a little better.  Thanks for the lessons folks!   .... and thanks, Steve for the beautiful picture of Saturn and your suggestion for using the QHY IMG132E camera.