Joe Bauman wrote:
I use a refractor mounted on top, which is tied in to a Meade Deep Sky Imager that I use as an autoguider alone. But in this case, I think the telescope wasn't balanced right to accommodate the weight on top, and it wouldn't guide well. I need to work on balancing.
So your images are auto guided with the autoguider attached to a guide scope which is mounted on top of the main scope. And the images are shot through the main scope. Have I got that right? Have you considered using an off axis guider (I have one you could borrow)? That would allow you to guide on the same light that is hitting the imager. That would also allow some slop in the polar alignment as long as the exposure did not go too long. 'Course if the alignment is within a couple of arc minutes of the pole and the drive works well enough I'd think you could go a few minutes without having to guide at all. Which brings me to my next point:
I use the telescope's go-to method. I level and have the assembly generally pointing to the north star. Then I swing the tube around so it is in what Meade calls the "home" position and turn on the system. It makes a GPS reading then points toward Polaris. At that time I'm supposed to center Polaris by adjusting the wedge and alignment, not using the control keys. Then it swings around to some other bright star, almost always Arcturus, and tells me to center on it using the control pad. That's supposed to get the telescope properly aligned.
I'm not familiar with that method (no surprise as there are probably lots of methods I have not heard of). Does Meade say that method is intended for _imaging_? Again, I'm not familiar with how that method works but knowing what it takes to get a scope's polar axis within a few arc minutes of the pole using the drift method or even T-Point, I wonder if the go-to method is actually intended for visual use, not imaging. It occurs to me that one way to check all this would be to put a permanent pier in concrete in your yard and spend a LOT of time working on getting your polar alignment right. Granted, your skies would not be that great but for this experiment all you want to do is get to where you can produce nice, round, focused stars. Once you are to the point where you get virtually no drift in declination over say 5 or so minutes when viewed at prime focus through a 6 to 12 mm illuminated reticle (which I could loan you if you don't have one) you'll know your alignment is right. Then if the drift is still there you could do some simple experiments to see if it's caused by the drive or the fact the imager is not looking at the same light the finder is. Patrick