Is it necessary to adjust WB before you take the shot if you're shooting in RAW format? I've always just left it on Auto-WB and then adjusted the temp in PhotoShop when I needed to.

CoolCheech wrote:
Is it necessary to adjust WB before you take the shot if you're shooting in RAW format? I've always just left it on Auto-WB and then adjusted the temp in PhotoShop when I needed to.

No, it isn't necessary. The in-camera WB setting only travels with the image as metadata. Some people shoot a gray card and use that to set WB in the raw converter.

Usually you meter from a gray card right? I've never used one.

But here you're saying to shoot a photo of the gray card, and in Post-Processing get the WB temp from that image and use it as a guide for all the other images shot.
Is that correct?

ACR will analyze the WB and that slider is variable. I find the closer you get to the correct WB the better the RAW image will be.
I have ACR set to zero out on everything but WB seems to set itself from the WB setting or WB of the image not sure which, but it is the only slider that floats for me. The closer my setting the better the image.
This is off a D200, ACR3.7.

Tom

CoolCheech wrote:
Usually you meter from a gray card right? I've never used one.

But here you're saying to shoot a photo of the gray card, and in Post-Processing get the WB temp from that image and use it as a guide for all the other images shot.
Is that correct?

Right. Depending on the camera, after you shoot the gray card, you can use that image to set custom WB in the camera. Later when you convert the raw files, you can use that setting on images shot in those same lighting conditions.

But I generally just try to find a neutral tone in the image and use that to adjust WB ... first in ACR and then refine that (if needed) with a curves adjustment in Photoshop.

Setting custom WB with RAW isn't necessary but it is very beneficial because it controls how the image is initially displayed in the editor.

Human vision is very adaptable, which is why we use gray cards as references. When you open an off color (i.e. non-neutral) image on a monitor the eye will begin to adapt and normalize it perceptually in the brain. Its more subtle that in nature becuase there is also the reference of the ambient lighting, but it occurs.

So if custom WB is set in the camera, every image you see will have the same neutral baseline for color. That in turn should make it easier to make subjective judgements of whether the color should be left neutral, or made warmer or cooler to suit the mood of the photo.

In some situations, such as a photo of the sunrise or sunset, custom WB is not desireable. In any situation where the desire is to capture the ambience the eye sees the best strategy is to just use the closest menu setting: daylight outdoors or tunsten / fluorscent indoors.

Setting Custom WB doesn't eliminate the need for a gray card in the scene for monitoring. Clicking on the card in Photoshop is the only objective way to determine whether or not the Custom WB set in the camera did make the color neutral.

The most important concept to grasp is the need for consistent baselines in the color mangement workflow. Setting custom WB and using a gray card in the photo allow color to be set at a baseline of neutral.

If it is not possible to do custom WB or put a card in the shot picking the closest menu pre-set and using it consistently would be preferable to auto WB which "reinvents" WB in each shot based on the brightest area in the scene. When the brightest area is neutral white AWB produces neutral results. When the brightest area has a color tone the WB is skewed in the opposite direction in color space.

When setting custom WB I first set the camera WB to "daylight" before shooting the card. That isn't necessary, but after I set the WB off that frame I shoot the card again and flip back and forth between the two. The color shift in the playback, if any, provides a clue where the ambient light is relative to the daylight baseline.

Edited by cgardner on Apr 02, 2008 at 10:32 PM GMT

I agree with Chuck, It isn't necessary, but I find it very beneficial. I use a WhiBal card & set custom WB in camera when I can for two reasons, 1) it's faster in PP as I don't need to worry about WB--I know it's right already, and 2) from my experience the image color seems truer when done this way; massive WB adjustments still seem to have odd casts to me even coming from RAW. Then there's the examples Chuck provides where you want to lock WB in to attain a desired color cast.

Another advantage to setting the correct white balance is if you care about the Red Green and Blue channels of your camera's histograms. The in-camera histograms are based on the processed JPEG and not the RAW file. Having a very wrong white balance setting will have a big impact on these histograms so you may not get what you are expecting when it comes time to do your RAW conversion.

I am late reading this topic so forgive me. I shoot everything in RAW and use Light Room to pp the files. I just leave my cameras on AWB because I know that I will be changing them later if they don't look right. Later in LR I find the shots that I like and represent the scene best and use that data for most of the other photos I have shot.

My question is this; are you saying that I can simply shoot a gray card at the event and later use that data as my baseline when I pp the images in LR? That seems way too simple.

Thanks

if your lighting is sufficiently constant for what you shot, then yes, shooting a gray card once is enough to set white balance for the entire set of images. i don't know of too many types of photography where this would save you much time, however.

Herb...

if your lighting is sufficiently constant for what you shot, then yes, shooting a gray card once is enough to set white balance for the entire set of images. i don't know of too many types of photography where this would save you much time, however.

Quite a bit of commercial photography, and the sun doesn't vary all that quickly.

To add to what others have said, AWB is probably the least desireable mode for you to use. It will vary the color balance according to the colors of the scene, which will be much more variable than the actual light color changes. It's better to have been slightly off consistently through a series of images than to be off by varying amounts from image to image.

One further question-
I dont mean to complicate things but what the hell-

I shot raw with a consistent WB and a gray card in every different lighting condition im in. My question is regards the mode of wb. I have herd that if I leave it in AWB the WB shifts from shot to shot. Should i not use AWB with even with a gray card in the shot? Does it matter?
Thanks

photosenior wrote:
One further question-
I dont mean to complicate things but what the hell-

I shot raw with a consistent WB and a gray card in every different lighting condition im in. My question is regards the mode of wb. I have herd that if I leave it in AWB the WB shifts from shot to shot. Should i not use AWB with even with a gray card in the shot? Does it matter?
Thanks

AWB would work only if you had the gray card in every shot to click-correct the photo in Photoshop.

For example, you shoot a red wall with the card in it, in AWB. You can correct it by clicking the card with the eye dropper in PS.

Next frame you shoot a green wall in AWB but don't include the card. The green wall will cause the AWB to shift from the first shot but without the card you can't correct in PS.

But if you had set your WB to "daylight" the WB would be the same in both shots. Once you corrected the WB in the first (by eye since it wouldn't have a card) you could apply the same WB correction to the second file.

Thats what i thought, just wasn't sure.
Thanks!

cgardner wrote:
AWB would work only if you had the gray card in every shot to click-correct the photo in Photoshop.

For example, you shoot a red wall with the card in it, in AWB. You can correct it by clicking the card with the eye dropper in PS.

Next frame you shoot a green wall in AWB but don't include the card. The green wall will cause the AWB to shift from the first shot but without the card you can't correct in PS.

But if you had set your WB to "daylight" the WB would be the same in both shots. Once you corrected the WB in the first (by eye since it wouldn't have a card) you could apply the same WB correction to the second file.

That's not quite correct. I use AWB all the time, and I shoot a gray card (whibal) as one frame whenever the lighting changes. Then in LR (or any other raw converter, including ACR in PS), I click on the card to get the "correct" WB applied to that frame. then I copy the WB setting from that frame to every other shot using the same lighting conditions (I often tweak the setting anyway, using a color-managed monitor).

Your earlier post makes the point that setting a custom WB allows you to see the colors based on the included jpg or default used to display the image in the RC. That's an advantage if the raw converter can correctly read the camera mfr's proprietary metadata in the raw file. I recall reading that non-OEM raw converters do not always correctly read the metadata associated with camera settings, and their settings don't always match the camera's settings (OEM converters, such as DPP, have the same settings as the cameras made by the mfr, so they more reliably allow consistent settings, whether made in-camera or during raw conversion). As I recall, this was an issue for manually set kelvin temp and preset WB settings (daylight, shade, tungsten, etc); I don't know whether it's an issue for in-camera custom WB settings made using a gray card.

For me, I find the procedure outlined above to work well, since I sometimes tweak the WB setting anyway, and the whibal card gives me the most reliable starting point. If a custom WB setting based on a gray card is equally reliable, and you find setting custom WB easy to use, that should be fine too. But I use raw (among other reasons) precisely to avoid worrying about in-camera WB.

I can only comment on the non-OEM converter I use--Bibble Pro. But it does read the information off my 20D properly. After I've set custom WB off a WhiBal shot, or specific Kelvin setting my images convert correctly.

Auto this or that, WB is really up to you. You may set WB by any technical method but if it doesn't look right (start the discussions of calibrated monitors/ printers, etc) you can/should adjust for your, artistic, preference.

RAW makes no permanent WB adjustment just a, nominal, opening setting (whether Auto or Manual-K-WB) when opened in the RAW converter. The package of "development" settings is just an instruction set associated with the photo file.

Can someone please give me an idea how to batch process a bunch of images through ACR or DPP? I took a shot of a white card and now need to correct a bunch of shots to it.

Many thanks.

*bump*

Many approaches ... here is one:

1. Select all images (include reference shot) in Bridge.
2. Open in ACR (right click on one of selected images).
3. Edit reference shot (use white balance tool to click on reference).
4. Select all other shots then click on the synchronize button.
5. Now click on Save Images ...

Another approach:

1. Select all images (include reference shot) in Bridge.
2. Then go to TOOLS > Photoshop > Image Processor ...
3. Then complete dialog box selecting your reference shot as the image to process as a template for the others.

In my opinion, including a gray card in your reference shot is very important, especially for commercial work. It’s much easier to add a hue or effect to your image from neutral than to choose a great looking WB you happen to like. For individual images it’s not important, but if you have to match two images shot under different color temperature, it’s more work to match them completely.

In the studio, I always make the first image with their ID card and the second with the gray card. Every time I change lightning or color in the scene, I make a new image with the gray card (pointed to the main light).

Thanks guys. Just what I needed.