can you lock the aperture?

i want to get the HV20 but the biggest foreseeable problem with it is the shutter speed and aperture. i would like to hear from HV10 people as well.

my current understanding is;
you can set the aperture but the shutter speed will be automatic
or
you can set the shutter but the aperture will be automatic
but you can't set them both manually at the same time.

in "shutter priority" when you set the shutter to 50 (PAL) can you lock the aperture/exposure/gain?

so when you pan past a bright window indoors or go from sunlight into shade then into sunlights again outside - will the camera automatically change the aperture??

this would be a real problem for filmmaking.
is there any way avoid this?

thanks for your time.
patrick

can you lock the aperture?Yes you can. Previously discussed at http://www.dvinfo.net/conf/showthread.php?t=85370

Please direct any replies to that particular thread. Thanks,