How important is 'in camera' white balance?

[Murray Fredericks]

I shoot many interiors with mixed color temp light sources - often the full spectrum of possibilities in large spaces.

Question:

How important (if at all) is white balancing in camera. Does it actually affect the colors given that the raw files are interpreted and white balanced later in post?

Murray

[Roy]

How important (if at all) is white balancing in camera. Does it actually affect the colors given that the raw files are interpreted and white balanced later in post?

Murray
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Does not affect the raw file. However, the histogram shown on your camera when shooting is based on the jpeg the camera creates from the raw file. If the ambient is quite different from the camera white balance setting, the histogram may be misleading.

[Panopeeper]

How important (if at all) is white balancing in camera. Does it actually affect the colors given that the raw files are interpreted and white balanced later in post?

It does not effect the raw data the least. If correct WB in-camera is important depends on your preference. If you want to see a "realistic" thumbnail in the camera or if you want to extract and use an embedded JPEG (supposed your camera creates one), then the WB and other settings should reflect your post-processing intentions as far as it is possible at that point.

However, if you want to ensure that nothing or only irrelevant parts clips while the exposure is not too low, then the realistic settings are the worse you can have, because they steer away the histogram from showing the raw exposure.

See this thread:

http://luminous-landscape.com/forum/index....topic=22250&hl=

[Panopeeper]

I don't understand the above comment at all

You would understand it if you had read the thread I linked to. There is another approach; do you happen to have a shot of anything grey or white, but nothing else? Like a grey card occupying the entire image? If you do have such a raw image and you don't mind uploading it (for example via yousendit), I demonstrate you the contradiction between the raw histogram and the RGB histogram.

[marc gerritsen]

I shoot a lot of interiors and I never really set the in camera wb, exept if the client is around so he/she doesn't freak out about a totally the color.
Later i batch process my raw files for the exact wb, if i have 2 light sources like tungsten and daylight i might geneate two files with the relative wb and blend the files. It all becomes tricky when I have 3 lightsources and also 2 different exposures to combine.
A while back I stopped using a grey card to set the white-balance because it seemed that when i followed the true grey the overall tone of the photo might be correct for mid grey, but left me with a more colder feeling, that most people did not like as much as an overall warmer tone.
I now gage it by looking at it and thinking if my wife would like it, then it is all right. Not a very scientific approach but works wonders.
cheers
Marc

[Murray Fredericks]

I too have never worried about the white balance in camera and I'm always apologising to 'new' clients about the preview images.

Lately I have been having trouble with 3 source scenes. I also process the raw files a few different ways for the white balances and for exposures, sometimes I just desaturate an offending colour.

Lately though I have had trouble with 'big' corrections leaving me with no colour at all in stone or subtle walls and I was just looking at ways of recapturing that...Particularly troublesome are areas of subtle colour with two light sources falling on them...

I guess sometimes you just find the limits of what's possible?

I agree also with those that say feeling is the best way to white balance...
Cheers

Murray

[Roy]

I don't understand the above comment at all
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Neither do I.

Panopeeper, (do you have a real name?) if you are going to post a comment, you have a responsibility to write clearly.

Isn't the internet fun? Against my better judgement, I replied to this question. Now here we go with incomprehensible comments. I usually just stay away, but this seemed a simple and clear question with an obvious answer.

[Kirk Gittings]

I shoot a lot of interiors and I never really set the in camera wb, exept if the client is around so he/she doesn't freak out about a totally the color.
Later i batch process my raw files for the exact wb, if i have 2 light sources like tungsten and daylight i might geneate two files with the relative wb and blend the files. It all becomes tricky when I have 3 lightsources and also 2 different exposures to combine.
A while back I stopped using a grey card to set the white-balance because it seemed that when i followed the true grey the overall tone of the photo might be correct for mid grey, but left me with a more colder feeling, that most people did not like as much as an overall warmer tone.
I now gage it by looking at it and thinking if my wife would like it, then it is all right. Not a very scientific approach but works wonders.
cheers
Marc
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I almost always shoot in mixed light these days, much more so than I did with film. I agree with you, though I shoot a bracket with a grey card just for reference, gang process and balance midtones on image with greycard as a starting point, BUT like you it almost always seems to cold, especially for residential magazine work. I almost always warm it up from there.

[Panopeeper]

if you are going to post a comment, you have a responsibility to write clearly

The thread I linked to deals with this problem in several dozen postings. I just noticed, that the linked page does not show the links to the following pages, as if there were no further discussions.

The issue very briefly is, that one needs to see the raw channel histogram in order to judge how good the exposure was, but the histogram shown in-camera is based on the embedded image (usually a JPEG), which reflects the in-camera settings, like contrast, sharpness, saturation, color adjustment, and most notably, the white balance. The effect is, that the displayed histogram is far away from reflecting the raw data; consequently, it can show clipping, when it did not occur, but it can hide clipping, when it did occur.

The contrast, saturation, sharpness settings can be neutralized easily, but only a few cameras offer the option to neutralize the white balance application.

The linked thread introduces a technique of doing just that: prodding the camera into applying a "neutral" white balance, i.e. one, which does not change the proportions between the raw channels.

Btw, here is the link to the complete thread:

http://luminous-landscape.com/forum/index....showtopic=22250

[John_Black]

I almost always shoot in mixed light these days, much more so than I did with film. I agree with you, though I shoot a bracket with a grey card just for reference, gang process and balance midtones on image with greycard as a starting point, BUT like you it almost always seems to cold, especially for residential magazine work. I almost always warm it up from there.
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Here's what I find tricky --- how do you warm it up?  A simple change in the K value isn't always the answer (for me).  Usually I start with setting the general K value followed by the tint biasing.  This really is like cooking - "season to taste".  From there if it needs "warming", my standard "warming fix" is the WB hue @ 40 and the WB saturation @ 5-10%.  This amps up the image's yellows.  This works for landscapes, I'm not sure if it would be appropriate for interiors.

Where this process drives me crazy is with the back's ICC color preset (I'm talking about a P25 here, so I don't know how it works with Leaf, Hass, etc).  Assuming I started with "P25 - Landscape" in C1, the above WB values were tweaked relative to the "P25 Landscape" color mapping.  If I change that preset to "Generic", "Natural Light Portrait", etc., then the previous WB values most likely do not work and the WB adjustment process starts all over again.

So..., where do you start?  How do you know the WB values set in C1 are "the" WB values when they will be shifted (sometimes radically) depending upon the camera ICC preset selected?  With the Canon 1Ds2 I very seldom had to adjust WB - maybe 1% of the time at the most.  With the P25 this has become one of the most important steps in the editing process.  It's a big change for me.

I have tried gray cards, but I don't think they works well.  Outdoors is similar to indoor shooting with mixed light.  Outdoors there is direct sunlight, the light passing through foliage such as trees (thus a green tint), light reflecting off other surfaces (cement, water, grass, structures), etc.  Ultimately I looked at a bunch of 1Ds2 RAWs in C1 and wrote down how C1 interpreted the 1Ds2 AWB values.  For example - a desert sunset was 5100K with -4 tint.  I wrote down these values for about 20 different scenes and this became my cheat sheet for quick starting points.  I took several of these values and added them to the P25 as custom WB presets.

I so, so much would rather have accurate AWB in the P25...  And I'm thoroughly convinced that the wrong WB can lead to an incorrect histogram on the P25 - as others have mentioned here.

[yaya]

The thread I linked to deals with this problem in several dozen postings. I just noticed, that the linked page does not show the links to the following pages, as if there were no further discussions.

The issue very briefly is, that one needs to see the raw channel histogram in order to judge how good the exposure was, but the histogram shown in-camera is based on the embedded image (usually a JPEG), which reflects the in-camera settings, like contrast, sharpness, saturation, color adjustment, and most notably, the white balance. The effect is, that the displayed histogram is far away from reflecting the raw data; consequently, it can show clipping, when it did not occur, but it can hide clipping, when it did occur.

The contrast, saturation, sharpness settings can be neutralized easily, but only a few cameras offer the option to neutralize the white balance application.

The linked thread introduces a technique of doing just that: prodding the camera into applying a "neutral" white balance, i.e. one, which does not change the proportions between the raw channels.

Btw, here is the link to the complete thread:

http://luminous-landscape.com/forum/index....showtopic=22250
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Just a small correction;

Leaf backs can show the separate channel histogram as well as the luminance one and they do it from the RAW file not from a JPEG. The preview image is being re-generated every time a parameter changes (sharpening, curve, Input profile, WB etc.).

I would recommend using a Grey card in the images so you can either set the WB on the back (zoom in and pick the Grey card, then save it) or you can do it in post, but at least you have a good neutral starting point.

Yair

[bjanes]

The issue very briefly is, that one needs to see the raw channel histogram in order to judge how good the exposure was, but the histogram shown in-camera is based on the embedded image (usually a JPEG), which reflects the in-camera settings, like contrast, sharpness, saturation, color adjustment, and most notably, the white balance. The effect is, that the displayed histogram is far away from reflecting the raw data; consequently, it can show clipping, when it did not occur, but it can hide clipping, when it did occur.

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To supplement what Panopeer has said, the raw histogram is particularly important for photography under tungsten lighting, because this light is very weak in blue. White balance is achieved by multiplying the red and green channels by a coefficient so that they equal the green channel. For example, with the Nikon D2x the red and blue coefficients are 1 and 3.17 respectively. The blue channel is actually 1.67 stops underexposed.

Here is a raw histogram showing white in an image taken under ~3000K (40 watt bulb) with the D70 (3000K red multiplier = 1.11, blue = 2.53):

[attachment=4882:attachment]

As you can see, the blue is far to the left. One could equalize the histogram by placing a blue filter over the lens, which would transmit the blue light and hold back the red and green. See the article below for details. An 80a filter would do approximately, but might not be ideal since it would bring the white balance to daylight, which is not the native WB of digital cameras (for daylight a magenta filter is need for that purpose to hold back some of the green).

[a href=\"http://tedfelix.com/Photography/Filters.html]Filters for Digital[/url]

[siba]

What John_Black touched on is an interesting issue. What is the starting point? What should you set your back to initially? Do you always carry a grey card and give yourself a custom balance? Obviously, if you're shooting something on a tripod in a controlled environment where the light is not going to be changing then use your grey card. Silly not to. But, there are times when this is not always practical, or we're lazy, or we've left the grey card in the studio, or we just don't have one.

On my p45 the in-back presets work just as badly as presets on any of the few cameras I've used. They compensate for what they think is correct, but then you're shooting something blue, or yellow, etc. and it's all suddenly horribly off. What I learnt early on with my back was to never use the presets, because they were not constant.

What I've done for the last couple of years is to create a custom balance from my my profoto flash, and I have left my white balance on that for almost everything. This gives me a pretty neutral pleasant white balance, which works well in most scenarios - especially mixed light sources and daylight/lightbulb mix.

The important thing is to have a constant white balance that looks to your taste, which you can then very quickly and easily tweak, or change, as a batch in capture one (or other software).

[John_Black]

Siba - I think you and I found the same solution   My default custom is 5100K with a -4 Tint; pretty middle of the road for landscapes in sunlight; and pretty close to most strobes (I shoot Elinchrom and those are supposed to be 5500K).  By no means is this perfect, but it's something in the vicinity.  

This past Xmas my wife and I were hiking in some foothills outside of L.A.  Altitude was probably 500-750 ft and we were overlooking the valley floor.  Later we were at ~6000 ft.  In order to get a decent gray card reading, I would have needed my wife to be Supergirl so she could hoover in space about 100 ft in front me with a giant gray card.  We're shooting on the side of a mountain - so where do you place the gray card?!?!  

I mean all this in good humor, but my point is simple enough - gray cards are not a practical solution.  I've thought about trying an Expo-disc to see how it does, maybe that will be "good enough" for on-site WB.  I would like to know what is so different about a Canon or Nikon dSLR that they can get a reasonable AWB.  The Canon 1Ds2 and 1Ds3 don't have a WB sensor on the camera body, so that's not the issue.  I'm assuming Canon is basing their WB off the raw file content, so why can't Phase do a better job?  Leaf and Hass don't even offer AWB on their backs.

[marc gerritsen]

I have raised the AWB or rather the absense of it way back with Hasselblad and they said they were working on a firmware upgrade in which there would be an AWB.
This was a while back and nothing has since appeared, so who knows.
Regarding an acurate grey card reading on the side of the mountain, I can imagine how you feel about that John! My experience in the last few years is to really take my WB issue in a painterly way. If I, but mostly other people like the warmth or cold then it is ok. When shooting product in a studio, that is an other ball game and my grey card is certainly not absent then.
cheers
marc

[snickgrr]

Just wondering.  Does Phase offer an ability to do shadow, midpoint and highlight balance in their software like Leaf does?

[John_Black]

If you mean boosting the mid-tones in the shadows for more detail and recovering highlights?  If so, yes in C1 Version 4.

[snickgrr]

No, I mean when I shoot a Macbeth color chart, Leaf allows you to neutralize three points using the dark patch, the midpoint grey and white patch.

[Morgan_Moore]

(for daylight a magenta filter is need for that purpose to hold back some of the green).

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This is to me a very interesting snip

SLightly off topic - sorry - but I am convinced that most digicams I have owned roughen skin making it blotchy ie exagerating darker skin areas

These areas of skin probably contain more magenta than nice areas of skin

Are you saying that digicams in general are oversensitive to green (correcting this difficciency in the digital processing of the image)

And therrfore a better startpoint would be to have a magenta (ie green cut) filter in front of the lense when shooting

I have already tried improving skintones with an IR cut with no joy

SMM

[rljones]

i used a fixed color balance. it is much easier to adjust later rather than have the camera do an AWB and each image is different. on the e75 i keep it on Sunlight.

on cameras which allow adjustment, i put on a fixed temperature, usually 4500 degK with magenta adjustment for sensor as determined by prior macbeth testing. this just gets me in the ballpark. if actual temperature way off, then i may adj temp to 6000 or 3000, depending upon conditions. but i try not to change for most shots.

while raw data is not altered by these settings, most raw developers load the settings and i've found this makes for more rapid adjustments later. fixed settings are so much easier than having a AWB changing each image.