In order to control where the output images go for the miGen job,
you need to enable the "Export File Paths" option when you submit the
job, and specify the "Output image" path.
If you inspect the output .mi files from the job (look for the line
that refers to your "camera", such as 'camera "perspShape"', and then
find the "output" line (a couple of lines) below it), you'll see the
output file path.
If you specify "Absolute" path for output images, then you'll end
up having "output" lines with absolute paths in the .mi file, and
you'll find the images there.
Otherwise, your .mi files will describe the output line in a relative path.
Your images rendered by mental ray standalone will be relative to where
mental ray runs. By default, that's where the input .mi files are located
(which can be controlled by the "mi Export Directory" parameter).
With the qubegui submission, you may override this value by specifying the
"Working Dir" parameter.
