BVRI Filter Positions, DSI OAG Focus, QSI/DSI FOV, ASCOM Connections

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I removed the QSI from the MegaPort SideWinder (MPSW) and disassembled the filter wheel chassis to take note of the BVRI and no filter, filter wheel positions. The following positions are entered into MaxIm DL:

Position Filter
-------- ------
1.    B
2.    V
3.    Rc
4.    Ic
5.    No Filter (empty)

Before the filter wheel chassis was reassembled and the QSI re-mounted to the MPSW, I inspected for any dust and blew out using a pressurized can air.  The QSI was re-mounted to the MPSW without incident.

The DSI had to be placed quite far out from the MPSW OAG side port.  Rather than use fixed length extension tubes, I dug out my Meade Basic Camera Adapter (#07356) which has a sliding-cell assembly to vary the length.  The DSI was mated to the adapter using T-threads, and the 1-1/4" nose piece is inserted in the POI.  It turned out that the adapter sliding-cell could not reach focus, so I trimmed off about 20mm from the top of the inner tube.

I determined the spacing to bring the DSI to focus at the side port as 88mm from the top surface of the POI to tube/DSI T-thread connection.  This spacing is locked into position using the two thumbscrews on the sliding-cell of the adapter.

I took images of a star-rich field with both the QSI at the MPSW rear port and the DSI at the MPSW side port.  Using the stars in the images, I was able to calculate the FOV of each imager for the f/7.1 focus of the SCT-ACF as follows:

QSI 516ws FOV
Pixels = 9w x 9h
13.8mm x 9.2mm
1536 x 1024 pixels
0.64"/px
16.5' x 11' (0.275 x 0.183 degrees) @ f/7.1

DSI FOV
Pixels = 8.3w x 8.6h
5.59mm x 4.68mm
752 x 582 pixels
0.64"/px
8' x 6.2' (0.133 x 103 degrees) @ f/7.1

I was then able to determine the off-axis FOV off-set for the DSI and set the off-set in TheSky.  The off-set is:

16' 19" from centre of main imager to centre of OAG

The connections that work to set-up ASCOM are:

1. AP V2 ASCOM driver > Mathis Mount on COM3

2. ECU > MaxPoint Hub

3. MaxPoint > AP V2 ASCOM Driver >

4. MaxIm DL > MaxPoint Hub

5. DDW Telescope Slaving > AP V2 ASCOM driver