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Old Dec 31, 2006, 1:20 PM   #1
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Can anyone explain W/B and how it works..When to adjust and when not too...

What it's for....Most likely time to use it....

Come on Guy's and Gal's help us out..!!
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Old Dec 31, 2006, 3:03 PM   #2
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Not all light is the same color.

Compare the yellow light we see in most normal homes lit by incandescent bulbs to the bright white light at midday to the cooler bluer light under clouds or a clear blue sky.

Then throw in the different temperatures under rooms lit by fluorescent lights or the totally different color caused by flash.

The camera has to judge this and basically guess, indeed under normal room lighting the typical camera gets it very wrong, with the result colors look false or strange color casts are introduced.

If you want to just use auto, you can try to correct in post processing.

However many modern digicams allow you to point the camera at a white sheet/piece of paper/wall and push a button to tell the camera "that is white"

More advanced cameras even allow you to select exact temperatures in kelvin.

Note in some cases you may not want to correct the white balance, ie taking pictures of sunsets etc, you want the deep red and yellows to set the mood.

Here is a picture of a piece of white paper, under normal indoor lighting, a 100w bulb, on the left as auto white balance sees it, on the right with custom set white balance.




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Old Dec 31, 2006, 3:54 PM   #3
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Thanks for explaining W/B.Now i'm going to ask how to correct white Balance using the Manual settings...I understand where the W/B is on my 30D, but... ( -/+)...(-) being less W/B and (+) being more W/B which makes things more White....How do i know when to stop on W/B Control...??

When i take a Picture indoors the Picture always comes out Orangey/Yellow sort of colour....( For our American Friends--("Color")...Obviously down to W/B
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Old Dec 31, 2006, 4:17 PM   #4
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wrams wrote:
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Thanks for explaining W/B.Now i'm going to ask how to correct white Balance using the Manual settings...I understand where the W/B is on my 30D, but... ( -/+)...(-) being less W/B and (+) being more W/B which makes things more White....How do i know when to stop on W/B Control...??

When i take a Picture indoors the Picture always comes out Orangey/Yellow sort of colour....( For our American Friends--("Color")...Obviously down to W/B
your white balance is not a + or - setting, you have several white balance settings to chose from though. Auto, Daylight, Shade Cloudy, Tungsten, Fluorescent, Flash, a custom setting that you can set up yourself, and a color temperature setting if you know the kelvin temperature of the light source. There is a color temperature correction adjustment that you can also use which is like putting a color correcting filter on your lens. So if you are taking indoor pictures under normal incandecent/tungsten lighting you would set your white balance to that setting which looks like the light blub on your camera lcd panel on top of the camera. Now if you shoot in RAW format you can adjust your white balance in post processing too.
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Old Dec 31, 2006, 4:29 PM   #5
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I always shoot in RAW and did'nt realise there where differnet settings for W/B...Better take an even closer look at the Manual...Thanks for you Info...
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Old Dec 31, 2006, 6:28 PM   #6
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If you "always shoot in RAW", why bother ... WB is virtually irrelevant with RAW files, where you would edit it yourself in the RAW software (I generally use Adobe Camera Raw).

Now, if you are shooting .JPG files, where the camera's own processor algorithms make the decisions, then, yes, you might need to set WB in certain circumstances.

I shoot RAW, eschewing WB on-camera, and take care of it in ACR.
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Old Jan 1, 2007, 9:14 AM   #7
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Is Adobe Camera RAW in CS2 or a seperate Program...???

Been messing about with W/B and Wow i didn't realise it made so much difference..


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Old Jan 1, 2007, 11:41 AM   #8
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hgernhardtjr wrote:
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If you "always shoot in RAW", why bother ...
So that you don't have to set it later. ;-)

Most Raw Converters (including ACR) can use the camera's white balance settings. That's because the RGB multipliers associated with the camera's white balance are stored in the metadata in a raw file's header.

So, by selecting the "As Shot" White Balance, the raw converter will apply it during the conversion process. That way, you do less tweaking later.

In difficult lighting, you often need to do more than just move the temperature slider, too (as you've got to worry about cyan/green sliders that are taken into consideration by the camera for getting the RGB multipliers just right to get rid of color casts). A custom white balance setting takes that into consideration.

Even if you don't use a custom white balance on the camera, it's a good idea to take a photo of a gray or white card in difficult lighting that a raw converter can use later during conversion (many raw converters have an eye dropper that can be used to sample the shot and apply the correct white balance during conversion).

I use Auto White Balance most often outdoors, and generally use either a preset (Tungston, etc.) or Custom White Balance in artificial lighting. With Flash, I generally use a Kelvin Temperature.

That way, I don't have to tweak the white balance much later during raw conversion using the camera's "as shot" white balance (unless I make a mistake like leaving it set to incadescent when I decide to take a flash shot indoors). lol


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Old Jan 1, 2007, 11:43 AM   #9
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ACR works/comes with CS2 ... free downloadable updates (current version 3.6 adds support for more cameras).

And JimC is completely correct ... but I usually have far more time in front of the computer than trying to fiddle with WB in a rush while trying to shoot.If you shoot RAW, leave WB in Auto, shoot away, and, if necessary, when you edit select the appropriately namedbalance in ACR or adjust it with the sliders if you have to tweak. It takes seconds.

And, FWIW, I too take a shot of a gray card (or my hand in a pinch) in tough lighting conditions as it helps greatly in getting colors just right later ... and that is also when I usually try to use a custom WB.

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Old Jan 1, 2007, 11:58 AM   #10
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Shooting in RAW mode,you have complete control over white balance when post processing,including light temperature control. This really lets you work on effects... a cool or warm effect will change the entire look of a photo. Look up "Kelvin" and learn how to use custom white balance. It'll open new doors to you and help you get exactly the coloration you want.

Have a great New Year!
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