Hi Euwen,
If i recall correctly, you bought this mount with the primary intend for astrophotography, so i will write from this perspective.
By nature of all GEM, goto and tracking is never going to be accurate on ANY mount regardless of price, if the mount's mechanical alignment are out by more then a degree form True North (which is more often then not). This cause the object to be everywhere except the in the centre of fov. i am confident that all celestial objects (except moon ) coordinates are accurately enough and should be of little concerned with the starbook program.
If possible, spent some time on drift aligning the mount before goto alignment. If the mount is square to polar axis. You will find that alignment of only one reference star is all you need for accurate goto.
ETX or other goto fork mounts scope in alt/azi (less GPS) are extremely forgiving on north alignment and yet could delivers very accurate goto. This depends heavily on the accuracy of the 2 star alignment. The downside of such setup is that field rotation is going to limit images to 2 min and rather random tracking errors. So Alt/azi fock mount setup is ill suited to meet your long term goals in deep sky photography.
IMHO, The determining factor of a good mount is the extend of periodic errors (or rather the lack of it). If possible, attempts to quantify the PE with your webcam and KD3CCD would put mount performance in true perspective. Your sphinx mount is equipped with goto and very soon... autoguiding features. Should consider it as a very good mount by all counts.
Cheers
Matthew
sturdyness of a mount
hey hi matthew! thanks for the info, it just shows how little i know haha.. after using the sphinx for some time i still dont have a feel of what its potential is and how far i can go with it. still very unfamiliar with alot of the technical aspects about this stuff.. and lacking in some of the equipment i need to discover this mounts potential. from the vixen sphinx yahoo group, some people have measured the mounts PE to be 20 arcsec peak to peak. its from this website if anyone is interested: http://www.astrosurf.com/demeautis/ep/sphinx.htm
yup anyway thanks again matthew!
eu-wen
yup anyway thanks again matthew!
eu-wen
hi eu-wen,
i second matthew's sentiments exactly. with a 25mm LV on the R200SS mounted on the SPHINX, I had no problems with getting general DSOs within the field of view, just like the GPD-SS2K combination. Just had to make sure that the initial settings like latitude, rough compass north alignment is in most cases sufficient. Although it is quite an effort to do drift alignment, this is the case for the initial first few tries, with practice, it is actually like a snap of a finger. Let me know if you need further help in getting the sphinx aligned.
rcj
i second matthew's sentiments exactly. with a 25mm LV on the R200SS mounted on the SPHINX, I had no problems with getting general DSOs within the field of view, just like the GPD-SS2K combination. Just had to make sure that the initial settings like latitude, rough compass north alignment is in most cases sufficient. Although it is quite an effort to do drift alignment, this is the case for the initial first few tries, with practice, it is actually like a snap of a finger. Let me know if you need further help in getting the sphinx aligned.
rcj