plate solve and sqm 17

[zoltrix]

Hi Alberto,

I think the problem is that until you have completed the initial alignment process (selecting the two stars, centering them, confirming on the handset, etc), the co-ordinates that SharpCap receives from the mount may not be correct, which could throw off the plate solving process. Normally plate solving is used to properly center a target after the initial alignment is complete, I'm not aware of people using it in the way you are planning.

cheers,

Robin

Hi Robin

I have been reflecting on your point
I suppose that alignment is needed to map the sky
However suppose you want to center and track one only celestial object per time

Sharpcap asks the user for the coords of his target
the mount is initially in its home position then it slews to the target
from the snapshot you can obtain the final position of the scope
even though you use magnetic compass and bubble the error should not be higher than 15°
you plate solve to center the object
the path of the star is known so tracking should not be an issue

as far as I see a possible drawback vs traditional 2 or 3 stars alignment is the following :
If you want to track an other celestail object you must repeat the procedure from the beginning ( home postition etc )

[admin]

Hi,

so overall, that should work, providing you have two conditions

1) the initial position is close to the true home position so that the error when you have slewed is small (<15 degrees)
2) that your mount/ASCOM driver reports sensible co-ordinate values before you have done any handset alignment.

I use a Skywatcher NEQ6 for my main mount (EQMOD, no handset) and it works perfectly in this way.

Sometimes I use a Celestron SE8 mount too - this provides rubbish co-ordinates to the computer until you have worked through the alignment procedure on the handset (particularly in this case if the date/time have not been set).

So, the NEQ6 works fine in the way you describe, the SE8 will not - this is down to the individual behaviour of the mount and/or the mount ASCOM driver, and is really outside the control of SharpCap.

cheers,

Robin