Upgrading to a new scope

Steve,

I have the Celestron C9.25XLT on a CG5GT which is primarily used for astrophotography.

First let me say if you are interested in photography forget the 11" Celestron. The scope loads the mount with just as much weight as it can take. Therefore adding on guidescopes heavy cameras etc is just not gonna be an option.

The 9.25" will allow you to add somewhat and can be used for photography when autoguided. I've been using this arrangement for quite sometime now. As far as value for money goes it can't be beat IMO.

The C9.25" scope itself is generally accepted as the best schmidt cassegrain celestron make. It's rare to get a 'lemon' 9.25" as can happen with others.

However, after you've been using the CG5 for some time, you'll start to yearn for a mount with a bit better performance. You see one of the key factors for photography is the ability of the mount only to make small errors before those errors are autoguided out. If the initial errors are quite large, the star takes a little longer to be quided back to its original position. After a long exposure whith the star wandering around a bit you end up with the resolution of the image lost a bit, even if the stars look round on the photograph. This is what I'm finding with the CG5. I've had a great time with my CG5 and dont regret for one second, my purchase. For the price there is nothing like it. However, now that I'm trying to 'push the boundaries' of my imaging a bit, I'm finding that the mount is limiting what I can do. For this reason I'm now looking to upgrade to a mount with better performance. I'm now seiously looking at the celestron CGE mount.

I also owned an EQ6 once (the old non-goto version) and it was fine. I've heard good things about the new EQ6 skyscan. I do get the feeling though that like the CG5, the EQ6 will have its limitations when it comes to photography. However considering that you don't wanna blow your entire budget on a mount alone, it looks like the CG5 or EQ6 are your main options. Dave Lillis might have another opinion on this, but for seeing other peoples experiences, fork mounts are just too much trouble for photography.

Steve,
Dave Lillis might have another opinion on this, but for seeing other peoples experiences, fork mounts are just too much trouble for photography.

I wouldn't necessarily disagree with you Dave, after all, most of the best deepsky astrophotography is done with high end german equatorial mounts.

At this stage, I'm also contemplating changing over to a eq mount, which one I dont know yet.

I'm "beta-testing" one for Dave L at the mo!

fork mounts are just too much trouble for photography.

There are fork mounts out there that are as good as high-end GEM's. Unfortunately, they are designedand built for observatories and hence very expensive. You probably wouldn't be putting an 8" OTA on them...

Dave

True, if I had access to a good mechanics workshop , I'd have no doubt that I could refine the fork mount to work as good as any eq mount.

Even at that, its not really the fork thats the problem, the periodic error is the issue. The RA system is under alot of pressure when tilted (as it is when placed on a equatorial wedge) making it even worse as the RA balance (a slight constant imbalance is actually what you want) is not a constant for every RA position in the sky, making the periodic somewhat erratic at times.

To be honest, I've had enough of fiddling with the mount and just want it to work without hastle, so all going well (barring any mechanical breakthroughs with the orig fork mount) I'm going to get a german eq mount in the first half of next year, something I'll pick all the brains on the site about over the coming months.

Thanks very much for the feedback folks

Obviously the mount is the main thing here, in terms of euros my budget for mount and scope is going to be about 4000(and at that budget, hopefully a good 10 years of use), therefore, while I realise that Hubble type images will be along way off, I suppose, what I am looking for is a good value of aperture and mount for primarily visual observing(near future) with the photographic end being someting for the long term (even with a wedge) ... ie. upgradable.

keith, dave(s), dmc, michael, trevor, seanie... many thanks for your experienced and informative opinions. I was kind of leaning towards the meade lx90 10" lnt gps( but it is fork mounted) intitially.

what do you guys think?

Many thanx

Steve