BHC Loc: Strawberry Valley, JF, USA

I was involved in a photo meetup today inside a museum (not art). Photography was permitted. Most attendees used Auto WB, a few actually got presets for most shots and a used a recommended Kelvin reading. The Auto WB pictures were the best, but a thought occurred to me. When someone uses Auto WB and is reviewing the picture on the LCD, the information given is that the picture was taken using Auto WB. Does any camera also give the actual color temperature at which the WB was set at the time of exposure? It is not a critical piece of information, but might be helpful if a photographer could learn to use and rely on a Color Temperature Meter, especially if the lighting is mixed. Incidentally, the majority of the better pictures were taken with fill flash, in which the flash overpowered the interior lighting. Some of the Auto WB pictures taken by ambient light displayed odd lighting shifts.

Leicaflex Loc: Cymru

An interesting experience.

rjaywallace Loc: Wisconsin

Olympus and Panasonic MFT cameras use flash units (from both OEM and commercial sources) that offer and encourage adjustable output in order to obtain photos where the flash adds to and enhances existing lighting w/o having to overpower it. I know Canon and Nikon flash units have similar capabilities. Was pleased to hear that the Auto WB feature incorporated in modern cameras is performing so well. Hope you got the shots you wanted, Mogul.

SteveR Loc: Michigan

Just an aside. After doing a custom wb setting using a gray card due to fluorescent lighting, I forgot to reset my wb back to auto and wondered why I was getting such odd results until I checked my white balance.

pithydoug Loc: Catskill Mountains, NY

And a good reason to shoot raw and not care about WB until post. I do use auto WB even with raw, so the picture on the LCD, which is an on the fly jpg version, is reasonable viewable. Then you can do color correction for usually tough band lighting.

Rongnongno Loc: FL

If (and only if) you shoot raw it makes no difference other than the selection is used as a 'starting point' when post processing the image.

If JPG it makes a difference despite the apparent ease of changing the WB in post processing. This is done w/o the information discarded when the JPG was created in camera.

That said, still depending on what the file format was used the information displayed in camera is less than reliable (even with JPG).

Now, with all the caveats away...

A kelvin setting is a different name for WB, just much more precise to adjust and because of that much less accurate as it needs to be adjusted with each shot (using a JPG).

A WB preset works only in a specific situation so in a changing light environment it becomes a 'hit or a miss'.

AutoWB just creates a WB 'on the fly' so more effective in the same changing lighting condition.

Flashes, fill or not, are made to create only one type of light situation: daylight so it is not surprising if they are more 'pleasing'. In a fill flash situation only the subject should be lit 'daylight', it sounds like the whole shots were...

As to what the autoWB does, who knows as it will take into account the most preeminent light quality onto account so if the angle differ, the light differ and anything goes with it.

I might add that regardless of the setting WB works only as a 'wholesaler' meaning that you might want to correct a scene for incandescent but if in the frame there is a different light source these will not be 'correct' so PP may be necessary. In autoWB it is possible that it tries to create a Hybrid WB which will not work. A preset would avoid the problem.

I hope this helps some.

BHC Loc: Strawberry Valley, JF, USA

I guess I must have mis-worded my question. I would simply like to know if there is any camera that would display information such as:

AUTOWB-2800

on the screen in review mode.

Rongnongno Loc: FL

Yes, all of them! WB mode that is. :mrgreen:

BHC Loc: Strawberry Valley, JF, USA

Not the mode; I want to see the actual temperature the camera selected for any particular exposure, even in AWB.

pithydoug Loc: Catskill Mountains, NY

Not that I have ever seen! Just text such as incandescent. Now that has a range to help you zero in, if you know Kelvin #'s.

zigipha Loc: north nj

The actual WB value should be in the exif data

selmslie Loc: Fernandina Beach, FL, USA

Color temperature (primarily the blue/yellow adjustment) is only one of the variables affecting white balance. There is also the red/cyan and green/magenta trade-off. All three adjustments are made together during Auto WB using the camera's best guess for the ambient light in the scene.

You could also set it deliberately by placing a gray card in the scene and setting a custom white balance to get the red/green/blue values to be neutral - to produce the same tonal intensity. You can get the same effect in post-processing by finding a gray or white patch in the image and using the eyedropper to balance the colors.

But all of this is relatively useless if there are different colors of light illuminating different parts of the scene. This will happen when there are different light sources or large colored reflecting surfaces nearby. You might achieve a neutral balance in one part of a scene while other parts of the scene will be out of balance, as you have seen.

Rongnongno Loc: FL

Then you are out of luck.

amfoto1 Loc: San Jose, Calif. USA

That's right.

And, WB values are actually a combination of color temp (blue/yellow) and color tint (green/magenta). If you only set the color temp, you will actually only be setting up half the equation.

There are color meters that can accurately measure color temperature. Minolta made them in the past... so Kenko probably makes them now. They are fairly expensive.

Fluorescent lighting is particularly problematic because it cycles on and off at a high rate (120hz or 120 times per second, in the US. 100hz in many other parts of the world). The camera's shutter speeds are usually fast enough, and it's Auto WB and metering system too slow, to have trouble with fluorescent lighting. It effects both accurate exposure and color balance.

Canon 7D II (and possibly some other recent models) have a new Flicker Free mode that attempts to compensate for fluorescent... haven't used it personally, but have heard it works pretty well. Apparently what it does is try to sync the camera's exposure with the rapid fluctuations of the lighting. This might make for a very slight delay releasing the shutter.... but it would likely be so short that the photographer wouldn't notice it. If shooting bursts of images, it also might effect the frame rate (the 7D II can normally shoot at 10 fps).

Personally I never use any of the WB presets... They are, at best, just guesstimates that may or may not be very accurate for any given situation. I either use Auto WB or set a Custom WB. Not that it matters much... since I almost always shoot RAW and that makes it easy to tweak or change WB in post-processing.

selmslie Loc: Fernandina Beach, FL, USA

Besides the flicker, fluorescent has a non-continuous spectrum with a green spike rather than a smooth spread of light frequencies from UV through IR.

Incandescent lights have a smooth spread without the spike but their color temperature is skewed differently.

See also Characteristics of Common Light Sources.