Whats all this W/B stuff?

[Mike Newman]

What exactly does the white balance do and in what situations should I adjust it? I just bought my rig and don't even have it in hand yet but I am trying learn and read as much as possible. Thanks...

Setting the white balance on your camera fools it into believing that the ambient light resembles 'normal' outdoor daylight values. In other words, it will correct the blue or green colour cast introduced by changing light values underwater.

To use it your camera must be capable of setting 'manual white balance' (check your instruction book) and its underwater housing must allow access to this setting underwater.

The setting is made using a white or, in the case of some cameras, a neutral gray slate. You select manual white balance and point the camera at the slate. Knowing that the slate is a particular value, the camera then adjusts its colour sensing to give the correct solution in your picture.

Points to note - this will only work for ambient light photography. Any video lights or underwater strobes are already tuned to give realistic 'daylight' values. (But will only do so within their effective range). It may also be necessary to re-adjust any manual white balance for different depths. Although some very successful underwater photographers, e.g. Jim Church, simply recommend setting it at about 30 feet and leaving it.

Hope this helps - you might consider finding an instructor who can deliver PADI's excellent new 'Digital Underwater Photography' Course, which covers white balance and much more.

 

[KiiY]

Consumer video cameras don't have the RAW mode option that digital still cameras do. I'm not sure if even D1 or D5 offer that possibility. Never heard of it.

It would be nice if we could get there someday, though.

 

[Shasta_man]

Yes, RAW is only available to digital still cameras.

The RAW file captures all of the RAW data captured by the sensor and doesn't perform any compression or "improvements" that would be necessary to save to JPEG. So you can open the file and see what the camera saw, make adjusts and convert to JPEG.

 

[limeyx]

Consumer video cameras don't have the RAW mode option that digital still cameras do. I'm not sure if even D1 or D5 offer that possibility. Never heard of it.

It would be nice if we could get there someday, though.

Duh! I'm a moron -- I didn't notice this was in the videography section.
Sorry!

 

[yceltikci]

But see, now, MY question is, how does white balancing affect lighting? Do you need to white balance with the lights on if you're going to use lights for that shot, or does it not matter? My next setup with have HIDs, I'm really curious about all this.

Peacedog,

Unless you are in AUTO mode, whenever you change light source, you'd better W/B.
Let me repeat here that, the camera calibrates colors according to white. If you tell the camera "this is white" (meaning W/B) then other colors looks real. Otherwise blue's will look greeinish, cyanish and so on. If your lights are sunlight warm, and you change it to some other lights, then you have to re-WB.

That's what I understand frok your question.
Hope this helps.

Rgrds,
Yener

 

[yceltikci]

BTW, why do you have to use both hands to set WB?

One hand at grip, one hand at WB button. Slate??? :11:

Your second question---in a difficult positioning situation, such as you described, I would just set to Auto WB for shots like that. Unless you're shooting something really rare and unusual, it's not worth the trouble to attempt to WB that scene.

Understood. that's what I do. thnx.

rgrds,
Yener