Possible EMI between the Arrays and Autoguider CCD.
Autoguider CCD very close to IR arrays.
CCD and arrays clocked asynchronously.
Fast high energy CCD clocks could couple into array readout degrading images.
Screened housing with EMI window.
CCD cables completely screened inside cryostat.
CCD and detector array hardware isolated from each other.
Controlled grounding scheme to prevent coupling through grounds.