Custom white balance

[ahken]

Hello everyone
Attached here are the photos with custom white balance,but the images looks reddish(few photos shows greenish).I use small writing white slate to do CWB,i tried to shot at the white sand,with internal flash on/off but doesnt look good.This is my 1st time do CWB,something wrong with my setting?Thank you very much

 

[Cathy Church]

Yes, something is wrong. What type of camera are you using?

 

[ahken]

G11 with canon housing...what went wrong??

 

[ptyx]

It's hard to tell from just the pictures, but here are a couple of ideas:

Make sure you take your white balance correctly: card not too close from any subject (or from the camera), filling enough of the frame, ideally at a 45 angle to the surface.

Use a gray card rather than a white slate - white can overexpose and lead to incorrect white balance.

Maybe your flash is too warm (in term of color temperature) compared to your white balance setting - setting a manual white balance without the flash and then shooting with it will lead to weird results (not likely with the internal flash - but I'm running out of ideas).

Not sure about the G11, but some cameras ignore custom WB when shooting with flash (and use a 'calibrated' flash color temperature instead). That only leads to decent results if the flash is powerful enough to illuminate the scene.

And finally, the ultimate cure: shoot raw and adjust the white balance after the shots...

 

[ahken]

I use minimum flash output to do CWB,is it better if i choose max flash output?
i shoot raw but someone here suggested that it is better to shoot with CWB then edit later.
Thanks for the tips!!

 

[maged_mmh]

It's hard to tell from just the pictures, but here are a couple of ideas:

Make sure you take your white balance correctly: card not too close from any subject (or from the camera), filling enough of the frame, ideally at a 45 angle to the surface.

Use a gray card rather than a white slate - white can overexpose and lead to incorrect white balance.

Maybe your flash is too warm (in term of color temperature) compared to your white balance setting - setting a manual white balance without the flash and then shooting with it will lead to weird results (not likely with the internal flash - but I'm running out of ideas).

Not sure about the G11, but some cameras ignore custom WB when shooting with flash (and use a 'calibrated' flash color temperature instead). That only leads to decent results if the flash is powerful enough to illuminate the scene.

And finally, the ultimate cure: shoot raw and adjust the white balance after the shots...

+1

nice shot BTW

 

[Cathy Church]

PTYX gave offered some good ideas. But I still am not sure what went wrong. If you set the CWB in deeper water and then go shallower, or if you set it when it is cloudy and then the bright sun comes out, the photos will get too pink. If you set the CWB without the strobe and then add strobe light it will get very pink. I personally prefer to use a stronger, external strobe for foreground color and set the white balance on cloudy and not fuss with it further. I like the cool blue background and the warm colorful foreground.

 

[ahken]

Hi Cathy,
The photos were taken right after i did CWB,no diff in depth and the depth is more than 15m.
I dont have strobe, i use internal flash with minimun output,is it better if i set max flash output?
Still new to underwaterphotography,thanks for the tips!!

 

[ptyx]

The photos were taken right after i did CWB,no diff in depth and the depth is more than 15m.
I dont have strobe, i use internal flash with minimun output,is it better if i set max flash output?

You want to set WB in the exact same conditions you'll take your shot: flash output, distance from the subject and depth. Orientation as well, although in most cases it's not as critical.

The problem with WB and flash photography is that your flash will expose the subject to a certain color temperature, and the ambient light will be another color temperature. Assuming shooting with the flash doesn't override any WB setting (and that depends on your camera), if you set your WB without the flash, colors will be correct for the background (which isn't illuminated by the flash). If you set it with the flash, then your subject might look good but the background might be off.

Thinking about it, I suspect in your case you took your WB measurement too close to the lens - the flash color temperature overrode ambient color temperature, and then you shot a subject further away where ambient color was the dominant source of light.

Make sure to take your WB measure as far from the lens as you can. Zoom in if you need to.

The reason raw is a good idea if you have WB issues is that although custom WB is applied to raw, all the original information is still preserved should you decide to change the WB on the computer later. With JPEG, WB is applied, and picture is compressed filtering out the 'insignificant' information. If WB happened to saturate one color channel, some of those details might become significant again once you fix the WB on the computer - but they're not available any more.

 

[travis99]

Do these cameras have the ability to shoot in "raw" if they do you should be able to adjust the white balance on the computer.