C9.25 XLT - Is the search finally over?

[DaveGibbons]

Celestron C9.25 xlt SCT review –is the search finally over.

Heres the kit.

I hope this personal review of my C9.25 SCT scope and cg5 mount will be of interest to

People. I’ve been on a journey through the world of optics for a number of years now Buying and trying lots of scopes looking for what I suppose would be called an all rounder. Contrary to what some people might think I actually don’t have much cash and it’s always been a case of robbing Peter to pay Paul, although as my only vice I am allowed by the paymaster to spend a couple of quid now and again.

I purchased the 2 year old C9.25 XLT ota 2nd hand 2 months ago. It has had a couple of nice mods from the previous owner- who is a very experienced imager/observer/. It comes fully flocked internally with proper flocking from scopestuff in the States, the primary looks like it is floating in the air and it does improve contrast. It has been fitted with a dual rate focus knob with a fine 6-1 gearbox well constructed and makes fine focussing a doddle. Included was a very long dew shield again from Scopestuff that attaches snugly with a nice neoprene band. It came with a CGE losmondy style dovetail mount that I managed to swap with someone who had a GP/EQ dovetail for a c9.25. It also has Bobs Knobs fitted for ease of collimation.

Business end fully flocked - nice coatings.

It came with Celestron's standard 6x30 finderscope which is actually very nice optically but a tad small. I already have a Telrad and 9x50 RA finder the latter required a new bracket from Scopes’s n Skies before it would fit. I purchased a 2” adapter for the rear cell so I could use my 2” Televue Push fit diagonal. I am not a great fan of the SCT screw on diagonal, as they always seem to put your head in contact with the rear end of the scope due to the low profile.

Before I talk about optics a little bit about my mount. Its Celestron's badged Eq5 the CG5. The one big advantage over similar GP clones is the fact it uses the same 2” Stainless tripod as the EQ6. I have stripped down and regreased the innards as well as adjusting the worms so it has very little backlash and is very smooth. I actually sold my EQ6 to buy this mount- no I am not nuts- the reason being in my humble opinion, both Heq5 and Eq6 non-goto have a high frequency vibration on the motors that really does prevent you getting the most out your scope at very high magnification. I have had 2 heq5’s and 2 eq6 mounts and they all did it despite strip downs and regreasing (the Skyscan pros do not have this problem). The CG5 with dual axis Chinese drives does not. With careful balancing it handles the C9.25 Ota with absolutely no problem for visual use and short duration webcam imaging of moon and planets, it is also a relatively light mount to move around.

I have used the scope around a dozen times since purchase and optically it is everything I hoped it would be. On the moon using a binoviewer it gives views that take your breath away. The amount of detail is incredible, whilst contrast is on par with the 7” Mak I had even with the larger central obstruction (flocking helps) the extra light grasp gives it the edge on resolution along with a brighter image. Viewing Saturn one evening I swear I could see structure in the banding on the planet, the inner crepe ring is actually visible on decent nights. Cooldown is a bit of an issue though, indeed on some nights it takes the OTA the best part of 3 hours to reach thermal equilibrium and on one night of dropping temperature it never did after 5 hours!

Webcam Saturn

Webcam appenines

With a 32mm 2” eyepiece you can get M81 and M82 in the same field of view. The chaotic nature of m82 with it’s dust lane and bright knots of star clouds a wondrous sight. It will resolve the likes of M3 globular cluster to the core and has never failed to show the 6 components of the trapezium ever.

I have managed to detect a hint of the spiral shape and lightbridge in M51 with averted vision, although I’ve not yet viewed through the scope on a truly transparent night (don’t know if it’s just me but hasn’t the quality of our skies got worse over the past 12months)? Collimation is easy to get spot on and it actually holds collimation very well for several sessions with no discernible mirror flop when crossing the zenith. Open clusters m35, 36, 37 and 38 are shown in all their glory, the double cluster is just beautiful with the deep red older stars really standing out. On double stars I’ve had splits down to .7 arcseconds and see no reason why on the very best of nights .55 can’t be achieved. In fact everything apart from wide field vistas is within the C9.25’s grasp.

All this can be done sitting down with no collimation blues no problems with dewing mirrors( dewnot heater) no funny awkward angles enough aperture for most objects , it’s light enough to set up and pack up in 5 minutes and doesn’t need the rock of Gibraltar for a mount.

Bad points? Well as I said cooldown is an issue, also I had a few poor nights seeing when the larger aperture seemed to work against it – on those nights a 4” refractor would probably be more fun!

Slight niggles, why don’t they put a decent finder on it and a 2” visual back from scratch. Also when new the price is way too much at around £1400 for a xlt OTA.

So the search is over I’ve found the Swiss army knife of telescopes that’s me done!

Well no, you see I had a C11 a while back and it was like a C9.25 on steroids I am sure I can just get away with it on the CG5 mount!

Now if I can only persuade she who must be obeyed one final time. I PROMISE it will be the last time dear.

Cheers

Dave

[tom.yates]

HI DAVE, Great review mate i am looking to buy a Sct perhaps a 8" or at most the 9.25 to complete the setup and then i can put the scope thing to rest for good i have also been on the journey through the diffrent scopes and have ended up with the 7" apo and the 8" Mak newt I hear you say what do you want a 8"/9.25 sct for Well mate it is to take out into the field with a mate of mine when we just nip off for a hour or 2 the great all rounder.

[Chubster]

Excellent review......hmm now that does look a little better than mine....No..NO

or at most the 9.25 to complete the setup and then i can put the scope thing to rest for good

Here you go Tom..Got your name all over it

http://www.astronomy-uk.co.uk/smf/index.php?topic=4285.0

[tom.yates]

Thanks for the heads up and it would be at that price the boss would not be happy think a tube assem will fit the bill

[FLO]

Good review Dave

[George]

So when you selling it? :D

[DaveGibbons]

George, you know me better than I do Nah no cash mate !

[Astronut]

I've been researching 'scopes for a couple of months now and I'd already decided the C9.25 is a great all-rounder - thanks for confirming it

I'm getting a 12" Lightbridge dob. first but when I get into imaging I'll be having a look again at the C9.25 - maybe next year.

Have a look at this page and see what it's capable of:

http://www.frankbonneville.com/Astrophotography/index.html

[cygnusx1]

I've been researching 'scopes for a couple of months now and I'd already decided the C9.25 is a great all-rounder - thanks for confirming it

I'm getting a 12" Lightbridge dob. first but when I get into imaging I'll be having a look again at the C9.25 - maybe next year.

Have a look at this page and see what it's capable of:

http://www.frankbonneville.com/Astrophotography/index.html

Great images, but seriously what mount is that on and what sort of imaging equipment was used :shock:

[Astronut]

I've been researching 'scopes for a couple of months now and I'd already decided the C9.25 is a great all-rounder - thanks for confirming it

I'm getting a 12" Lightbridge dob. first but when I get into imaging I'll be having a look again at the C9.25 - maybe next year.

Have a look at this page and see what it's capable of:

http://www.frankbonneville.com/Astrophotography/index.html

Great images, but seriously what mount is that on and what sort of imaging equipment was used :shock:

That would be the mount that's normally supplied with it - a CG-5. In Frank's words he says (he) "....must be pushing it to the limit and beyond"

As for imaging equipment, have a read of Frank's posts (astrospearo) near the end of this thread posted earlier this year when I was asking about mounts for the C9.25

http://stargazerslounge.com/index.php/topic,11710.0.html