The way I think of it is that SGP has taken over control of the mount positioning. It's difficult to work for two masters so if your mount also has a pointing model then the two can fight about how positions are determined.
If there are places where you think the standards could be improved then please let the ASCOM developers know. Changes to the documentation are easy, it's all in the sources and if, for example, the documentation for the Sync command can be improved this can be done.
Changes to the specification are more difficult but are possible and we pay attention to driver and application developers who have concrete reasons for things that they need and are going to use. The Observing conditions standard came about as a result of discussions here.
But there are some issues:
- We will not break the existing specification. We will clarify its intent though.
- We will not add hardware specific functionality.
- We will not make application specific changes.
There are a couple of elephants in the room:
- We have no control over how drivers are actually implemented. There are no ASCOM police with (brutal) methods to ensure compliance. Driver authors can and will do their own thing.
- We are very limited in resources. Without help - real help from people who are prepared to contribute their time and effort in making and implementing changes - very little will happen.
However:
We are putting a bit more in Conform to check how Sync behaves. It will check:
- After a sync does the position reported match the sync position?
- After a slew to a nearby position does the position reached correspond to the position requested?
Both of these are positions as reported, not where the scope is actually looking.
The current documentation for Sync says:
Matches the scope's equatorial coordinates to the given
equatorial coordinates.
And
This must be implemented if the CanSync property is
True. Raises an error if matching fails. Raises an error if AtPark AtPark is
True, or if Tracking is False.
The way that Sync is implemented is mount dependent and it should only be relied
on to improve pointing for positions close to the position at which the sync is
done.
I'm not sure if this can be made much clearer (and IIRC I did change it fairly recently).
Chris