A Challenge for the IT Minded - G9 Hack

[BigJeff]

I've been struggling for a while with the issue of upgrading my current setup, I'm still reluctant to go "all the way" to an SLR because there's just too much baggage attached - although the LiveView and specs of the new Sony a-350 are tempting.

I thought the Canon G9 would be a fantastic choice, until I heard that it does not use TTL when shot in manual mode, but does in Aperture and Shutter.

So here is the challenge - is anyone out there smart enough to make a CHDK hack for the G9 to make it use TTL in Manual mode???

 

[scottg541]

Jeff,

TTL works in Manual mode on the G9, with my DS125 anyway.

Scott

 

[BigJeff]

Wow - that is amazing news.

I guess it's possible the camera operates differently when the flash is connected via the hot shoe rather than when using the internal strobe - my current Olympus certainly does that.

I do remain a little sceptical, so is there any chance you could do some test shots for me?

Should be simple and take only a few mins of time, although it'll feel a little odd using the housed camera in your living room!

Put the camera in Manual, and shoot several shots of something small in your home (an inoffensive item!). Keep the aperture and camera distance and flash geometry fixed (e.g. F8 from 2 ft) and vary only the shutter speed, from ~ 1/40 to 1/1000 in several steps.

Then post the photos with the EXIF still intact.

You may want to wait 1min between each shot, just to make sure the flash does not overheat.

 

[BigJeff]

I asked IKE the TTL question, here is the reply:

"No, the G9 does not do TTL flash in the camera's "M" manual mode, even if a Canon flash is used. However, you can set the strobe powers manually through the housing, much like you would with an EV Controller. The DSLRs, like the Rebel XT, XTi and XSi, do provide TTL flash control in "M" mode. For some reason, Canon decided to implement the flash control differently between the camera lines."

So scottg541, without the pictures I'm going to have to assume you "misunderstood" how your camera works.

 

[scottg541]

Wow - that is amazing news.

I guess it's possible the camera operates differently when the flash is connected via the hot shoe rather than when using the internal strobe - my current Olympus certainly does that.

I do remain a little sceptical, so is there any chance you could do some test shots for me?

Should be simple and take only a few mins of time, although it'll feel a little odd using the housed camera in your living room!

Put the camera in Manual, and shoot several shots of something small in your home (an inoffensive item!). Keep the aperture and camera distance and flash geometry fixed (e.g. F8 from 2 ft) and vary only the shutter speed, from ~ 1/40 to 1/1000 in several steps.

Then post the photos with the EXIF still intact.

You may want to wait 1min between each shot, just to make sure the flash does not overheat.

Hi Jeff,

I'm not sure what to tell you... That's the way i shoot with my G9... in manual mode, with ttl setting on ds125...

i can tell you that if i change the setting on the ds125 to different levels of flash output (e.g. 1/8, 1/4, full, etc.) it gives a range of exposures, vs if i put it on ttl, its consistently the appropriate amount of exposure on the area i've spot metered on.

Not sure about why ikelite would say that, I assure you i understand what ttl is and it works on my set up in manual...

maybe changing the exposure comp is not handled by the ds125? I never really change that since i usually spot meter and want the subject accurately exposed... or maybe it wouldn't work in evaluative metering or something...

Anyway, that's what i know. have a look at some of the more recent photo's on my smugmug site they are all shot in manual with ttl setting of ds125, they are exposed accurately.

Good luck, maybe i'm wrong, maybe someone else could share their experience.

Scott