Exposure problem with c4040z, faulty??

[song]

Hi, i took the same scene with the same subject under very strong backlight from sunlight. I am about 3m from the subject.

One shot using Program mode, the flash fired and the shot is good. Then immediately, i tried using shutter pirority using 1/300 and 1/800. Both shots have the flash fired but then in both shots, the subject is very dark with well exposed background.

These 3 shots happened with 5 secs. So no observable change in intensity of sunlight.

So is this faulty or what??

please help leh

 

[Midnight]

Hmm, I have a C2000Z but have never experienced this kind of problem. Check the EXIF data of the three photos and look at the exposure settings (aperture size, shutter speed, ISO). See whether all three work out to the same exposure value (EV). This might give you a clue.

 

[song]

Originally posted by Midnight
Hmm, I have a C2000Z but have never experienced this kind of problem. Check the EXIF data of the three photos and look at the exposure settings (aperture size, shutter speed, ISO). See whether all three work out to the same exposure value (EV). This might give you a clue.

How to calculate the exposure value??
In program mode, the A and S is different from the A and S in Shutter priority mode.

Furthermore, If the background backlight scene can be clear and correctly exposed, the exposure should be okay?? Then could it be a problem of flash syncho speed problem? That is to say that the flash can only function at speed of say less than 1/125 etc. But then, should not this be programmed into the logic.

 

[Tweek]

Originally posted by song
Hi, i took the same scene with the same subject under very strong backlight from sunlight. I am about 3m from the subject.

One shot using Program mode, the flash fired and the shot is good. Then immediately, i tried using shutter pirority using 1/300 and 1/800. Both shots have the flash fired but then in both shots, the subject is very dark with well exposed background.

These 3 shots happened with 5 secs. So no observable change in intensity of sunlight.

So is this faulty or what??

please help leh

let me hazard a guess here. When using shutter priority with 1/300 and 1/800, assuming the sunlight in the background is strong enough, your c4040 will be forced to use small apertures, maybe F5.6 or even F8. When you use such a small aperture, your flash power and range will be effectively diminished, which may explain why your subject was dark.

It will be clearer if you can check and post the shutter speed and aperture value of the first shot in program mode, and the shutter speed and aperture of the 2nd and 3rd shots in shutter priority.

 

[song]

Originally posted by Tweek


let me hazard a guess here. When using shutter priority with 1/300 and 1/800, assuming the sunlight in the background is strong enough, your c4040 will be forced to use small apertures, maybe F5.6 or even F8. When you use such a small aperture, your flash power and range will be effectively diminished, which may explain why your subject was dark.

It will be clearer if you can check and post the shutter speed and aperture value of the first shot in program mode, and the shutter speed and aperture of the 2nd and 3rd shots in shutter priority.

Got it here :
3rd shot (shutter priority, underexposed subject with well exposed background at abouut 3 m) : 1/800 f2.3

2nd shot (same as above) : 1/320 f3.6


1st shot (program mode with good expossure for subject and background ) : 1/800 f2.6


Note that in all 3 shots, flash is fired.

 

[looteer]

song,

if program mode is okay just use it lah!! why use shutter priority?? anyway, i guess metering comes into play as well.... and your internal flash will meter TTL.....

 

[Midnight]

Strange. All three photos have more or less the same exposure value, i.e. EV=12. In fact, your camera's program mode chose more or less the same exposure settings as your 1/800s shutter priority shot. I presume the ISO setting remained constant, right? I am quite perplexed as to why your built-in fill-in flash did not work... Any technical experts out there can suggest any possibilities?