scottfiji
Contributor
Ahken, don't use CWB when using the internal flash, just use auto white balance. Use CWB just for ambient light shots.
Scott
Scott
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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.
Ahken, don't use CWB when using the internal flash, just use auto white balance. Use CWB just for ambient light shots.
Scott
Hi Scott,
So for ambient light shots , i dont have to use internal flash to CWB?
BTW , i learned a lot a lot of useful tips and techniques from ur underwaterguide.com!!
Very useful website for a newbie like me.Thank you so much!!
The distance between white slate card from my lens is about 15cm when i do CWB,just enough to fill the frame ( too close?)
Thank you so much ptyx!!
1. In order for White Balance Correction to have the desired effect, the entire spectrum of light must reach the sensor/film in the camera. Anything less will produce an incorrect colour reproduction.
2. In order to achieve the full spectrum of light below a couple of meters, you must compensate by providing additional light in the form of an external (to nature) source of light, usually a strobe or strobes.
3. When shooting RAW, you are in effect choosing to cook the product yourself and the camera does nothing but give you the available ingredients. In this case, your results are unprocessed and you need to apply the full scope of development including colour correction, white balance, sharpening and so forth. Many times people forget that they are taking over the function that the camera normally does when processing the light to create a jpg file for you.
1. I am not sure all photographers are looking to have the same desired effect from WB correction. If you desire to have the photo look like it looked to your eyes at the time of the shot, at depth your eyes are not seeing the entire spectrum of light. (see #2 above)
3. Shooting RAW gives one the option of modifying all the data recorded by the sensors, in a smaller file size than other lossless file types. A tiff is twice the file size of a raw file on my 5050, but they are both lossless, are they not? If I shoot F5, 80th with my strobe, many results will require no post processing. Ambient shots in P, Auto also may not require any post processing to look like my eye saw it. Does P, Auto function differently in raw than jpg?