Quote:
Originally Posted by Atmos
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In the interim however, I did start off with using EQAlign as a way of doing the drift alignments. Free software and it does work really well, doesn't have the "real time" feature that PemPro does but it works well all the same. I have seriously considered purchasing PemPro and may still do it in the future, even if just as a way of getting some damn good PEC curves  |
I've tried and used EQAlign a while ago. OpenPHD/PHD2 is also free, and it's drift align tool is realtime. It's also much easier and quicker than EQAlign in my opinion.
Quote:
Originally Posted by Atmos
I do agree with the sentiment that I am probably going a little over the top for a lowly EQ6 Pro It doesn't have the most accurate encoders, many seem to suffer with backlash (although I haven't really noticed any yet with my limited usage). Not say it's not there, just haven't pushed it far yet. |
Accuracy of encoders and backlash has nothing really to do with it. As per my comment to Peter below, if you have accurate polar alignment, everything else falls into place and is easier - pointing, guiding etc. You can't have pinpoint stars without accurate polar alignment unless your exposure times are unrealistically short for the sort of gear I understand you're using.
PHD2 (free) has a very simple and quick drift align tool for accurate polar alignment. You'll be polar aligned in minutes.
Astrotortilla (free), Elbrus (free), PlateSolve2 (free), Astronomy.net local server (free) are all plate solving tools that will solve an image taken in any part of the sky and sync your mount.
Quote:
Originally Posted by Atmos
There are a couple of reason I did choose to go down the path of TSX over PemPro for alignments though. Using TPoint takes an all sky model, takes refraction out of the equation. For a temporary setup it is debatable as to whether the difference is worth the effort, I do agree with that. For what I am planning on doing, I do need pointing accuracy though. When I get everything up and running I plan to start doing astrometric studies on a few dozen globular clusters over several months. I have an interest in RR Lyrae stars and want to do some research into the variability of variable stars (they have a ~40 day cycle). This involves slewing from one cluster to another, taking one image and then moving on. Accurate pointing makes my life much easier to say the least.
I am also planning on having a semi-permanent setup both at my house in Melbourne and my dark site in Heathcote. When they get established, having strong TPoint models already done means I'll only have to do a resync to them, 15 minutes and I am up and running 
Right now my mission is to work on one aspect at a time. First it is getting to know TSX, then auto guiding, then sequencing. Sequencing will probably be done through SGP running with TSX for mount control. As much as I love MaxIm, I haven't sat down to learn Visual Basic to write sequencing scripts for it yet. Maybe in the future! |
If you're talking about using SGP, all of my comments above are even more relevant, as they all work seamlessly with SGP. You tell it you want to go to a target, it will slew there, automatically take an image, plate solve it, if you're not bang on it will adjust and autoslew to target, solve again just to check, and off you go. Seamless, simple, quick, accurate.
Quote:
Originally Posted by Atmos
I know that within about 40 minutes from power up I should be able to be pretty accurately polar aligned (enough for me to be happy with a temp setup), have a 60-100 TPoint model and be ready to go. I have a digital level which gets me quite easily to within half a degree and I am looking at making a mount attachment for my compass to get me within a degree from cold setup.
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Forget the TPoint model and you can be ready to go in less than half that time, without losing any accuracy as per comment above
Quote:
Originally Posted by PRejto
Colin,
I'm sure you know this but as long as T-Point knows where it is at you can have pretty sucky polar alignment together with extremely accurate pointing. If your exposures are going to be short pointing can take priority.
Peter
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Surely for imaging an accurate polar alignment should be priority number one? If that's bang on, everything else falls into place - your pointing is more accurate, your guiding is easier, you don't get field rotation etc.