Canon G9 / Macro & Autofocus

Hi All -

Just returned from Alona Beach over the Chinese Newyear holiday. First time underwater w/ my G9 in the canon housing w/ a Inon z240 strobe (used in manual most of the time with the 1.5 diffuser - worked very well once I had found a "calibration" exposure setting).

The set-up is easy enough to handle, except for the autofocus in macro mode. For some reason, the camera almost never managed to get the subject into focus (I used the function that allows you to focus on that box you can move around, flexizone I think its called). I was at ISO 80 all the time and f5/6 most of the time. The macro subjects typically where on/in the reef, so the light was not great and contrast was almost non-existant (i mean, that oerang utang crab really is hard to distinguis from the corrals its is sitting on) and I did not generally use the aiming light on the Inon as a focus light.

Are you experiencing the same behavious w/ your camera and if so, is the only resolve to add a dedicated focus light? I also tried putting the camera in Manual Focus, but (a) when focussing, the machine only very very slowly adjusted focus (unlike when outside the housing when its rather quick - must be a bad connection or something) and (b) my eyes cannot see what's focus sharp through the goggles and all. So I need to rely on Autofocus for my sanity.

Your thoughts much appreciated!

Arie

I don't own the G9 but used an old Oly for quite awhile.

I did not generally use the aiming light on the Inon as a focus light

Click to expand...

Typically small, low contrast subjects are a challenge for any camera. If you don't want to use the light inside your Z240 then buy a cheap, dedicated focus light. You'll be amazed at the difference. BTW...I agree with your focus assessment with a P&S. I tried several times to manually focus with my old SP350 and it was hit or miss. However for macro you just need to get close and then move your camera rig closer, or further away, to bring it into focus.

Thanks Gary for your comments. So it is the lowcontrast that's causing the troubles, understood. I will go and find myself a cheap focus light then. Cannot use the aimlight of the strobe, cause i try to use that the light the subject area such that the subject is not "dead on", but bit aside from where the flash hits hardest. Think I read somewhere that's the way to do it and want to play by the rules for the time being -- its hard enough figuring out what works anyway.

Tried to MF focus trick for macro by moving in and out but found it frustrating (i am easily frustrated when a camera does not do what I want - fortunately my ancient Rolleiflex never gave me troubles, but this digital stuff is in a different league) but that to me is back to the old days - if there's an AF system in the camera it better fr%Ak^ng works, what's the point otherwise.

I'll need to get me transported back to the beach asap to try this out. Thanks!

arie

Forget multi focus. For UW macro, use center focus, period. Also, frame your shots. Move the camera slightly in, slightly out and take about 3-4 shots to make sure you get one that's sharp.