ASCOM Hardware Control

Focuser Control

The focuser can be controlled by using the In and Out buttons. Between each pair of buttons (coarse and fine) are the step size adjustment controls which allow the amount of movement per button press to be adjusted. The current position of the focuser is shown and it is also possible to directly type a new position value into this control (after typing a new value press <Tab> or <Enter> to move the focuser to the typed value). The Reverse checkbox swaps the meaning of the In and Out buttons - handy if the focuser moves in when pressing Out.

Filter Wheel Control

ASCOM Filter Wheels are simple to control in SharpCap – the buttons show a list of filters available and all that is necessary is to select the desired filter by pressing the appropriate button. It is best to avoid trying to change the filter again while the wheel is still moving. The names of the filters shown by SharpCap can usually be configured in the ASCOM driver configuration dialog for the filter wheel.

As with all ASCOM hardware in SharpCap it is possible to temporarily disconnect from the device by unchecking the Connected checkbox and the ASCOM driver configuration can be shown by pressing the Setup button.

SharpCap also contains the option to configure and show controls for a manually operated filter wheel. When using a manually operated wheel you can select the currently chosen filter in SharpCap, allowing the filter name to be used in custom filename templates.

Mount Control

SharpCap can connect to and control most ASCOM mounts (unfortunately, if the mount does not support the ASCOM MoveAxis functionality SharpCap will not be able to use it).

On the left-hand side of the control, the current Azimuth, Altitude, RA and Dec are shown – these are updated from the mount on a regular basis, so should update if the mount is moved using another application such as a planetarium program.

The centre section of the control is home to the movement buttons which allow the mount to be moved from within SharpCap. The up, down, left and right buttons will move the mount in the given direction while they are pressed. If the mount is an equatorial mount, Up/Down will move the mount in Declination and Left/Right will move the mount in RA. The mount will be moved at a speed that can be selected using the Rate drop down in the top-right of the control. This lists the movement rates that the mount makes available (this drop down shows slower movement rates in multiples of Sidereal rate – i.e. 1x, 2x, 8x – and faster rates in degrees per second). The STOP button between the direction buttons will stop any current movement of the mount but is not normally needed as movement is stopped when the direction buttons are released.

The Spiral Search button (top left of the button group) moves the mount in a growing square spiral around the starting point while it is held down. This is useful when trying to locate an object such as a planet that may be just out of frame. Note that like the movement buttons, the speed of movement of the Spiral Search is governed by the Rate dropdown. If the Spiral Search button is released the spiral movement will stop. Pressing it again will begin a new spiral around the current location – it will not resume the previous spiral pattern.

The Plate Solve button (bottom left of the button group) will perform a plate solve on the current image, re-synchronize the mount’s location to the plate solve result and will the GOTO the original target co-ordinates. This has the effect of putting the target into the centre of the field of view even if it is off-centre or out of view entirely. This button only becomes enabled if a compatible plate solver is detected or configured. See Plate Solving Tab for more details. Note that when plate solving is launched from this button, it will restrict its search to sky locations within 15 degrees of the current location as reported by your ASCOM mount. This dramatically improves the speed of plate solving, but does mean that if the current mount location is highly inaccurate, plate solving will fail.

The Park checkbox can be used to park or un-park your mount.

Finally, the Tracking button (bottom right) can be used to turn sidereal rate tracking of the mount on or off. If tracking is turned off, stars and other objects will appear to drift across the field of view. To the right of the Tracking button is a drop down that shows (and allows you to change) the current tracking rate. You can select sidereal, solar or lunar tracking rates. The ‘?’ icon shows when the selected tracking rate is a custom rate.