Connecting SBIG AC4040 to PlaneWave 20 or 24

I'm often asked what is needed to connect our SBIG Aluma AC4040 Ultimate Package to a telescope, such as a PlaneWave CDK20 or CDK24.

You can calculate the backfocus of the SBIG items using the backfocus calculator spreadsheet on the main page, DOWNLOADS section for your camera. Or click here:
https://diffractionlimited.com/downloads/BackfocusCalculator.xlsx

Typically you will have a table like this:
Aluma AC4040 Camera 0.855in 21.7mm
Filter Wheel, AFW Series 0.550in 14.0mm
Filter 3 mm thick -0.039in -1.0mm
StarChaser SC-3 0.870in 22.1mm
Adaptive Optics AO-X 1.049in 26.6mm
========================================
Total Backfocus 3.285in 83.4mm

On the PlaneWave side, they have a standard SureFit adapter plate that uses the 4-inch bolt circle we have for the STX10018 adapter plate that camera with the camera - you don't need this, and can save some distance.

You likely will need a setup like these parts from PlaneWave:
IRF-90 Focuser / Rotator
600327 SureFit Adapter
600328 SureFit Adapter
200395-3 Adapter for Fingerlake Cameras to SecureFit Spacer 3"
600337 Adapter 3"-24 female to SBIG AO-X/STX-FW bolt-pattern

The 600337 is the "magic" that adapts to your SBIG stack of equipment. It replaces the 10018 adapter we provide. It fits the top of the AO-X, or SC-3, or AFW or FW7-STX, or AC4040/2020/STX/STXL.
Both SBIG and another brand of cameras use the same 3-inch x 24tpi thread size, however you can save space using the SBIG and PlaneWave parts mentioned above.