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Old 09-10-2011, 05:58 AM
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frolinmod
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Join Date: Dec 2010
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Index out of range usually just means that your raw pointing is so far off that you're nowhere near where you think you are. Way off. Not even close. Plate solves won't work when you're that far off. This is usually only the case prior to your first calibration run right after setting the mount up.

If you're off, but not way the heck off, you can make them work by going into Tools->Preferences->Advanced and increasing the "Bad pointing sample criterion (degrees)" value. This is the setting that controls this "sanity check." Increase it within reason, it's there for a reason, to warn you that you're way the heck off.

Also, any time you set up your mount for an observing session at a new location, after homing the mount and syncing on a star and prior to your first automated calibration run, manually map three or more stars on each side of the meridian. Make sure to map at least one star at a high declination and one at a low declination on each side of the meridian.

Here is my usual polar alignment and calibration routine. This assumes that the finder and scope have already been aligned. I'll gloss over steps like attaching the camera and focusing it and stuff like locking down your mirror if you have an SCT (always lock it down before doing an automated calibration).

1. Consult GPS receiver and make sure computer time is correct and that I have entered and set my correct location. Connect to and home mount.
2. Use TSX to slew to a star near the celestial equator at least 5-degrees away from the meridian.
3. Manually move the whole mount and tripod to center star.
4. Go into Telescope->Tools->Bisque TCS->Utilities and clear the sync history, Go into Telescope->Tpoint Add On->Setup->Tpoint Add On Settings->New and start new Tpoint model, Go into Telescope->Startup and sync on the star, go into Telescope and Add Pointing Sample.
5. Manually slew around to a half dozen stars on each side of the meridian, center them and add some pointing samples.

Now we should have good enough pointing so that plate solves (image links) will succeed.

6. Go into Telescope->Tpoint Add On->Calibration Run and start an automated calibration run of 25 or so points. Let it run. Finish it and click on supermodel and accept the model. Make suggested polar alignment changes. (Note that when I fire up a calibration run, I always have it first determine the image scale and position angle. I also enter the actual humidity and atmospheric pressure. I actually get a little better results this way.)

Now we should also be able to sync on a linked image instead of a star. This is better.

7. Clear sync history, start new Tpoint model, take a picture, image link it, sync on linked image.
8. Fire up an automated calibration run of 25 or so points. Let it run. Finish it and click on Supermodel and accept the model. Make suggested polar alignment changes.
9. Repeat 7 & 8 until I'm happy (usually two more times gets me to sub arc minute polar alignment).

Now we're polar aligned. Let's improve our pointing and tracking by running a really big calibration run.

10. Clear sync history, start new Tpoint model, take picture, image link it, sync on linked image.
11 Fire up an automated calibration run of 180 or more points. Let it run. Go look through other folks scopes for awhile. Finish the calibration run and click on Supermodel and accept the model. Turn on ProTrack.

I hope I got that right. If I've forgotten anything else, I'm sure someone around here will point that out...

Last edited by frolinmod; 09-10-2011 at 07:11 PM.
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