I'm quite suprised my Mike's advice - the 12" on a fork with a wedge and piggy backed guiding; but he would know - few of us are in the realm of experience and capability Mike has achieved. Question for you Mike - can someone new at the game set up the wedge easily and is the Meade gear that robust that piggybacked guiding won't bring differential flexures issues to ruin .
Cheers all, Matt
Yeah, I'm surprised too . Really Mike, a 12" portable fork/wedge Meade at 3m FL with external guide for long exposure DSO as a starter?.
Differential flexure is just the start, PE ?.
I have some experience too, sounds like the fastest way to dso imaging hell to me experienced or not, specially not
Target wise it will be planetary stuff and the easier (and larger/brighter) DSO's. I wouldn't attempt to do the harder stuff without more specialised gear, which will come later its part of the eventual plans too
With that comment in mind, have a look at what you can do with a bit of aperture, without spending all that money on fancy equatorial mounts...
Yeah, I'm surprised too . Really Mike, a 12" portable fork/wedge Meade at 3m FL with external guide for long exposure DSO as a starter?.
Differential flexure is just the start, PE ?.
I have some experience too, sounds like the fastest way to dso imaging hell to me experienced or not, specially not
Clearly our experiences were different On the native fork, reduced to between F4 - F6.7 (Meade, Optec and Lumicon reducers) and using an 80ED guide scope piggyback plus the small chip Starlightxpress camera I was quite happy with the performance and although my imaging skills were just developing then (2004), I think the images attest to that. I generally used 4min exposures this seemed to be the sweet spot but sometimes 5min and occasionally 10min. The mount autoguided very well at these focal lengths.
All the new stuff available today plus the better optics of the ACF to cover larger chips = a very capable outfit actually, both for visual and imaging
Mike
Last edited by strongmanmike; 18-01-2012 at 12:16 AM.
No doubt they are achiveing fantastic results, but they won't reach the level of portability i will want from this scope. At some point in the future no doubt when I want a bit of everything, i will want a massive dob to complement my collection, just not from what I want out of this one right now.
No doubt they are achiveing fantastic results, but they won't reach the level of portability i will want from this scope. At some point in the future no doubt when I want a bit of everything, i will want a massive dob to complement my collection, just not from what I want out of this one right now.
Sounds like you already know what you want. For what it's worth, an 18" truss tube dob will fit in the back of a Corolla hatchback. There are also ultra-compact designs that are easier. It's ultimately your money!
Cheers.
I have the 10" ACF, and you really do need to add a crayford focuser to it if you want great focus.
I have had the 10" and 12" side by side, and for visual on that night, there wasn't really a perceivable difference, and it won't be drastic for imaging, but the 12" will require a substantially beefier mount.
If I was going to get a mount that size, I'd pony up for a 2nd hand C14 instead and be done with it.
The 10" ACF vs a 11" non HD Celestron means your swapping coma and some mirror flop versus 18% - 21% more light reach. I hate mirror flop or sag - it makes guiding so tricky that piggy backing or side saddling a second scope isn't a real option. Note Mike said its possible with the Meade - which comes with a Mirror lock and a motor focuser that can be computer controlled.
Depending on your target choice will be the outcome of whether you rate light grasp over reduced coma and easier guiding. Knowing today what I know about tuning a rig to guide at long focal length - I'd guess the 10" ACF beats the C11's useability on a lot of targets for astro photography.
Be very interesting to hear from folk that had tried each OTA in this regard. Coma doesn't worry me much - there is very little to the edge of the frame on my C9.25, but mirror shift was a pain for a longer time!
Meade seemed to design better mirror locks, Celestron oopsied there IMHO. Note the above mentioned stopper only sells for the C14 - never seen one on a smaller Celestron SCT. With it you till have to have a hole in the back of your OTA.
If you're set on that path - drill and thread 6 holes and insert 6 nylon bolts to lock the mirror and add maybe one or two fans as well. But that's a lot of dissamebly, machining and re-assembly and aligning before you're ready to play (plus ass you said add a cradford focuser).
Why not just say Celestron forget this - whoops and go 10" ACF with its in-built mirror lock and a motor focuser? Simpler all round!
. Really Mike, a 12" portable fork/wedge Meade at 3m FL with external guide for long exposure DSO as a starter?.
On the native fork, reduced to between F4 - F6.7 (Meade, Optec and Lumicon reducers) and using an 80ED guide scope piggyback plus the small chip Starlightxpress camera I was quite happy with the performance and although my imaging skills were just developing then (2004), I think the images attest to that. I generally used 4min exposures this seemed to be the sweet spot but sometimes 5min and occasionally 10min. The mount autoguided very well at these focal lengths.
