I'm using CHDK with a G9. One of my uses for my G9 is to shoot large panoramas using a Gigapan Imager, which I since stitch together with AutoPanoGiga. I shoot my panos in AV mode, as a fixed aperture is critical to ensure good stitching. In low light situations, the exposure naturally becomes longer (especially as an aperture of f/8 can be quite desirable to ensure good field-of-depth), and here I run against a Canon imposed limitation, as the exposure time in AV mode cannot exceed 1 second. I can of course hardwire aperture and exposure in manual mode, but that is not feasible, as the correct exposure can vary wildly across a scene (consisting of hundreds of pictures).
So, have I overlooked the way of overriding the 1 second limit using CHDK, or can it be accomplished in some way through uBasic or Lua? I'm perfectly fine with the existing AV mode (indeed automatic exposure is necessary, as some of my panos consist of 500-600 images), but I would like access to longer exposures.