Problem with flash photography (Metz 32Z-1)

[darkness]

I'm having problems with exposure using flash as the main lighting source. All my pics consistently seem to be unexposed if I use the flash's recommended apertures. For e.g., if I set to ISO200 on the flash and use the 2nd aperture setting, the flash recommends f/5.6. If I set f/5.6 on the camera, I'll get an unexposed image. Anyone having this problem as well?

The other issue is that a bounce card is supposed to give diffused lighting right? How come with a bounce card I still get very harsh lighting (although slightly better than direct). Ceiling flash still works the best for me. Also, what should be the flash zoom to use with doing a ceiling bounce?

[mpenza]

use ISO 100 for the flash and ISO 200 for the camera and use the same aperture.... see if it works better.

Quote: Originally posted by darkness I'm having problems with exposure using flash as the main lighting source. All my pics consistently seem to be unexposed if I use the flash's recommended apertures. For e.g., if I set to ISO200 on the flash and use the 2nd aperture setting, the flash recommends f/5.6. If I set f/5.6 on the camera, I'll get an unexposed image. Anyone having this problem as well? The other issue is that a bounce card is supposed to give diffused lighting right? How come with a bounce card I still get very harsh lighting (although slightly better than direct). Ceiling flash still works the best for me. Also, what should be the flash zoom to use with doing a ceiling bounce?

Hmmm.. Use manual on the Flash for full power loh.. then u play with the aperture on ur camera...

[Zerstorer]

Quote: Originally posted by zephyr Hmmm.. Use manual on the Flash for full power loh.. then u play with the aperture on ur camera...

Not practical to do this as it will cause unecessary drain on batteries and affects the intended DOF as well. Flash cycle times would increase greatly as well.

Doing this basically turns the auto flash into a normal manual flash.

[xdivider]

Quote: Originally posted by darkness I'm having problems with exposure using flash as the main lighting source. All my pics consistently seem to be unexposed if I use the flash's recommended apertures. For e.g., if I set to ISO200 on the flash and use the 2nd aperture setting, the flash recommends f/5.6. If I set f/5.6 on the camera, I'll get an unexposed image. Anyone having this problem as well? The other issue is that a bounce card is supposed to give diffused lighting right? How come with a bounce card I still get very harsh lighting (although slightly better than direct). Ceiling flash still works the best for me. Also, what should be the flash zoom to use with doing a ceiling bounce?

I've been using flash setting equal or greater to my camera settings in indoors cos it seems that pictures that may look juz nice in the lcd may come out slightly underexposed on the monitor. Ur mileage may differ. U tried using a tissue to cover the flash together with the bounce card? Saw a set up in a website where the guy used both a omnibounce and a flash card. Haven had time to try that out yet cos i'm busy chasing the wabbit all over the house

[mpenza]

for xdivider, one thing to do is turn down the brightness of the LCD. the default settings are too bright.

[xdivider]

Quote: Originally posted by mpenza for xdivider, one thing to do is turn down the brightness of the LCD. the default settings are too bright.

I noe but sometimes i need to use manual focusing indoors so need some extra lcd brightness to play with.

[darkness]

Thanks all for the tips, some comments:

mpenza, I tried what you mentioned, but it still came out a little unexposed. I dunno why, but it seems that the flash doesn't really care what ISO you set it to be. It seems to only change the distance and aperture scale, but it doesn't change the flash power. If I set the flash aperture setting to the 2nd setting, at ISO 100, the recommended aperture is f/4, at ISO 200, the recommended aperture is f/5.6, but the flash power is the same. To get a "correct" exposure, I need to manually compensate by +2/3 EV in camera.

xdivider, I actually have this problem that the 2s review of the image looks ok, but when you switch over to play mode the image looks darker than the 2s review pic (underexposed). Do you have that problem? I've already set the image brightness to quite low liao (to match with the screen).

Quote: Originally posted by darkness Thanks all for the tips, some comments: mpenza, I tried what you mentioned, but it still came out a little unexposed. I dunno why, but it seems that the flash doesn't really care what ISO you set it to be. It seems to only change the distance and aperture scale, but it doesn't change the flash power. If I set the flash aperture setting to the 2nd setting, at ISO 100, the recommended aperture is f/4, at ISO 200, the recommended aperture is f/5.6, but the flash power is the same. To get a "correct" exposure, I need to manually compensate by +2/3 EV in camera. xdivider, I actually have this problem that the 2s review of the image looks ok, but when you switch over to play mode the image looks darker than the 2s review pic (underexposed). Do you have that problem? I've already set the image brightness to quite low liao (to match with the screen).

Try setting the slider to the far left "A" and then use about +1ev and see how...

[mpenza]

Quote: Originally posted by darkness Thanks all for the tips, some comments: mpenza, I tried what you mentioned, but it still came out a little unexposed. I dunno why, but it seems that the flash doesn't really care what ISO you set it to be. It seems to only change the distance and aperture scale, but it doesn't change the flash power. If I set the flash aperture setting to the 2nd setting, at ISO 100, the recommended aperture is f/4, at ISO 200, the recommended aperture is f/5.6, but the flash power is the same. To get a "correct" exposure, I need to manually compensate by +2/3 EV in camera.

hmm... just to confirm. did you do the following and get underexposed pics:

you set the flash to ISO 100 and get F4. on the camera, you set to ISO 200 and F4 also.

[darkness]

Maybe I should post some pics to explain the situation better. All the pics are taken at 1/1000s to prevent ambient light from affecting the pic.

At the 1st aperture setting on the flash at ISO200, the flash recommends an aperture of f/2.8. To illustrate the "uselessness" of adjusting the ISO on the flash, I took the following 3 pics:

Set flash at ISO100, aperture recommended = f/2
Set flash at ISO200, aperture recommended = f/2.8
Set flash at ISO400, aperture recommended = f/4

In theory, all these 3 settings when changing the flash sensitivity should provide the same flash power (increasing ISO sensitivity but at the same time stopping down aperture = same EV).



All 3 pics are taken with ISO200, f/2.8 (as recommended by flash). All 3 have the same exposure, but all of them are unexposed.




Now I set the flash at the 2nd aperture setting, flash recommends at ISO200, an aperture of f/5.6.



This pic is taken at ISO160, f/4. This corresponds to a +2/3EV compensation compared to what the flash recommends, but is the correct exposure (in fact, I think it can even tolerate a +1EV compensation).


All pics taken with ceiling bounce.

Is this kind of manual compensation normal? I'm a total newbie to flash photography, and this kind of behaviour really confuses me. How accurate is the light sensor on the flash really? Are we also expected to do our own manual compensation when taking light (compensate +EV) or dark (compensate -EV) subjects as we are expected to without flash?

[Zerstorer]

Darkness,
After you apply EV compensation to a particular set of settings for a proper exposure, are you able to carry on shooting and reliably get properly exposed pics? If so, there shouldn't be anything to worry about.

Normally, if you bounce, EV compensation is also needed as compared to a direct shot.

[mpenza]

you need to compensate when you bounce. sometimes, +1EV is necessary. Even some TTL flash needs compensation to ensure proper exposure. I was reading Tom Hagon's guide for Nikon flashes and he recommended compensation whenever you bounce with a Nikon flash.

[darkness]

I think the flash provides consistent pictures if I do a +EV compensation, but the issue is that if I do that, I can never use the first aperture setting anymore, since it will definitely underexpose. That will also mean that I cannot use f/2.8 on my camera.

I dunno if the problem lies with the bouncing. I'm quite sure when I bounce, the flash emits more power (from the sound of the flash) than if I use direct. Anyway, the pic still seems underexposed to me in direct flash.



Flash setting: ISO200, recommended = f/5.6
Left pic: ISO200, f/5.6, +0EV
Right pic: ISO200, f/4, +1EV

From the histogram, it can be seen that the right pic gives better exposure than the left pic (which seems underexposed). This is in direct flash mode.

mpenza, can you do some testing with your flash and see if this kind of problem occurs? What I'm concerned is whether there's a problem with my flash (sensor problem or underpowered flash). Or whether it's just a mismatch of exposure between the flash and camera (as Tweek pointed out to me). You are the best candidate for this test since you are using the Metz 32Z-1 and S602Z as well...

[mpenza]

Quote: Originally posted by darkness mpenza, can you do some testing with your flash and see if this kind of problem occurs? What I'm concerned is whether there's a problem with my flash (sensor problem or underpowered flash). Or whether it's just a mismatch of exposure between the flash and camera (as Tweek pointed out to me). You are the best candidate for this test since you are using the Metz 32Z-1 and S602Z as well...

I sold off the 32Z-1 liao. It's just a mismatch of exposure between the flash and the camera. Actually, from my experience, it's likely that the camera is not properly specified (ISO 200 is actually ISO100). I've used the flash with another camera (Qv2900UX) and exposure is spot-on.

[darkness]

Quote: Originally posted by mpenza Actually, from my experience, it's likely that the camera is not properly specified (ISO 200 is actually ISO100).

You mean to say that we've all been fooled all along???

[mpenza]

Quote: Originally posted by darkness You mean to say that we've all been fooled all along???

dunno. have raised this issue before in dpreview but didn't get any good answers.

btw, I've PMed you twice we would deal tomorrow.

[reflecx]

Quote: Originally posted by darkness You mean to say that we've all been fooled all along???

Yes, we've all been fooled by Fuji. I've tested the metering of the 602 vs a SLR and found that Fuji's ISO is about double of what it should be. OTH, Canon's ISO rating is less than what it should actually be. ISO 50 is more like ISO 80.