Sadly there is no reply.
But better synchronization times will be great in normal photography too. Flash synchronization with Canon's compacts is something like disaster.
Longer flash synchronization time than 1/60 can be used with these features:
Original firmware - slow synchro ON
CHDK firmware - override shutter speed
CHDK firmware - use the function AUTO ISO ON (it works partially, but it is comfortable way)
Shorter flash synchronization time than 1/500 can be used with this features:
Original firmware - use ND filter (it helps partially, but it is comfortable way)
CHDK firmware - override shutter speed (still comfortable)
In both situations:
Original firmware - Tv mode-doesnt work and is limited by flash synchronization
Original firmware - M mode - it is least comfortable way. The manual flash was created by an idiot which works only in canon's company.
And the LAST SOLUTION is:
TRY DIFFERENT COMPANY. With my previous Minolta F200, I never experienced such limitation of every function like with Canon G7 and G9. For example, other companies have the shortest flash synchronization time usually shorter than 1/1000. But on the other side, other company has usually inferior picture quality and inferior focus speed.
