[rogerg (Roger)]

G'day all,

It is quite frequent that my plate solve attempts fail due to lack of known stars in the FOV. I'm looking for ways to improve the chance of a successful solve.

My problem stems from small ST7 chip coupled with relatively long 2190mm focal length LX200. I like the combination for other reasons so am not keen on further reducing the focal length or such solutions.

I plate solve mainly using CCDSoft coupled with TheSky. I attempt this most commonly automated using CCDCommander, which supports both Software Bisque and Maxim but not Astrometrica.

I also plate solve using Astrometrica sometimes manually.

The chance of a failure is much higher when using CCDSoft than when using Astrometrica. For example this morning the same FOV successfully solved in both, but with 8 stars in CCDSoft vs 44 stars in Astrometrica.

I think the difference in success between Astrometrica and CCDSoft is that I do not have USNO-B1 (80gb version) on disk at home for CCDSoft to utilise where as Astrometrica accesses it online through the web "on demand".

I would like to improve the chances of CCDCommander performing a successful plate solve. The following are the best ideas I have come up with:

1. Acquiring a copy of USNO-B1.
2. Purchasing TPonit such that my pointing accuracy is perhaps imrpoved to the point where I do not need to plate solve.
3. Purchasing a new camera that has a larger chip size but similar pixel size.

Of the above, option 2 is looking like the most realistic.

Option 1: It appears USNO-B1 is hard to come by. I have found an observatory that will put a copy on disk but you must send them a external HD etc. I expect total cost would end up about the same as TPoint or a bit more. The main down-side I see to this is TheSky would likely become very slow to use due to the enormous number of stars it would be handling, on my aging 2.6ghz machine.

Option 2: This may work but I am not sure if TPoint will be able to fully comphensate for my amateur LX200 with all it's associated inaccuracies to the extent that objects will always end up in the FOV.

Option 3: Not an option at this stage due to $$$$. ST-10XME is on the list, but year(s) away.

I'd appreciate input from anyone with experience or comments.

Thanks,
Roger.

PS - I have tried MaxPoint and while I prefer it's price to TPoint I found TheSky's usage of ASCOM unmanageable for my setup, it just didn't work smoothly enough to be reliable, so at this stage MaxPoint is not being considered, I would prefer to pay for TPoint.