I have a canon 500d running in a sea&sea housing with dual inon d2000 strobes. I am finding that running completely manually I can get the exposure correct. But when using s-TTL I'm finding it a little under exposed.
I am wondering if I have the strobe set up correctly or whether I should have the AF- assist preflash on (or not) and then do I need the magnet in the strobe (or not) for ACC. Currently I have the AF assist pre flash off and the magnet not in the strobe.
I know the 500d is said to be a 'preflash' camera but I'm not sure if that is something different from the AF assist preflash.
Any advice would be gratefully received!
cheers
I personally turn off the assist since it often causes the strobe to be not fully charged when it is time to go. I think for the 500D does not have a series of pre-flash and the magnet should be in.
Bill
My wife uses a similar setup (50D plus 2 x Inon S2000) and experienced the same problem when she changed from Z240s to S2000s. AF assist pre-flash was turned off and ACC magnet not installed (out). Initially the slight under exposure was overcome by winding up the Flash Exposure Compensation on the camera 1/2 to 1 stop. After playing around with different metering patterns we found that by using the Centre Weighted pattern instead of Evaluative a good TTL exposure was achieved without having to use Flash Exposure Compensation.
I should point out that my wife pretty much shoots macro only so the results may vary for any other type of shooting.
