need to try one of these

[zardos123]

these little gps units from pentax are getting cheaper, have a look at the results this guy is getting

http://poirierstephane.free.fr/photos/index.php?/page/astrophotography_without_equatorial _mount

can be had for couple of hundred new
regards brad

[Poita]

I had one, it worked great. I could get 50s exposures @200mm without a problem.