Custom White Balance compared to AWB

[William W]

When thrown, Bill? A Freudian slip, perhaps?

I reckon you are correct!
I was speed typing - I needed to leave my office, but I couldn't leave the conversation!
Yes I meant to type 'stinks'
The funniest jokes are always the ones you don't mean to make!

[Glenn NK]

Assuming that we are discussing the typical Eye Dropper Post Production Technique that reads the eyedropper from the Grey Card reference in the shot:

Using the Eye Dropper in a Post Production means that a little area of the image must be selected.

When a grey card is photographed in the field, the resultant image OF THE GREY CARD, may have various colour casts spread in areas / sections over the image of the grey card: this can be for various reasons, mainly reflections from neighbouring objects.

The salient point about using the Colour Temperature VALUE and the TINT VALUE as the camera INTERPRETED THE LIGHT (i.e. we are using the CAMERA as a COLOUR TEMPERATURE METER) - is to NULL all those little colour casts one gets when the image of a Grey Card in Photographed in situ.

I do not usually use the above described “eyedropper technique” for this main reason. There are also other minor reasons.

(Although you attest differently), I have found using the Eye Dropper Technique in PP actually LESS accurate and/or it takes a much longer time, to make accurate than what I have described above.


WW

This pretty well sums up why I gave up on my WB target. In the OP example, the light at/on the flowers has a different temperature than the light in the shadows at the left side of the image, so the technique must be used carefully. Even then, the WB won't be correct for the entire scene. This is so obvious when shooting a person's face when there is a shadow cast by the chin - the temps vary wildly. I tried to remove a "chin shadow" once and soon realized that the colouration of the "fixed area" was all wrong - I gave up.

I prefer shooting flowers on a cloudy day; some rain can add some interesting water drops.

Glenn

[Colin Southern]

This pretty well sums up why I gave up on my WB target.

At the end of the day, all it gives is a reference point. For portraiture it may - or may not - be enough, but if nothing else, it helps provide consistency that AWB doesn't. In something like a studio environment it's pretty much an open and shut case as all the lighting is the same temperature, but outside - as you've alluded to - things aren't quite that easy; even little things that people don't think of, like being a good photographer and popping the subject under a tree to shield them from hard light - popping them with some fill flash - and then wondering why parts of the face have a green tint ... coming from the "green light" (aka sunlight with natures "green gel" fitted in the form of leaves from the tree).

To be honest, some days it's the reason I'll just convert a shot to grayscale - it covers up a multitude of sins

[William W]

. . . For portraiture it [A White Balance Target etc...] may - or may not - be enough, but if nothing else, it helps provide consistency that AWB doesn't. In something like a studio environment it's pretty much an open and shut case as all the lighting is the same temperature, but outside - as you've alluded to - things aren't quite that easy; . . .

In the context of the Original Post I answered how I would (and how I did with the Rose Photo) ensure I get as close to possible to the hues that I observed in any specific shooting scenario.

In the context of generally “Making Photographs” I am NOT obsessed at all with White Balance (when using Digital) – in fact really don’t think about it much at all, I use Canon DSLR and I capture ‘raw + JPEG (L)’ and nearly all of the time leave the WB set AWB and I do NOT use any reference card.
When I do shoot under (exclusively) Flash - I set Flash.
When I do shoot under (exclusively) Tungsten I set Tungsten.
And - as previously mentioned when I shoot under low wattage indoor AL, I set the WB to the lowest value degrees Kelvin.
Generally I use the JPEG file, but if I want to ever fine tune the image I use the raw file.
AND that fine tuning just might (and usually is) ‘to my taste’ and doesn’t have much to do with what is the “correct” Colour Balance

In the context of Colin’s response and Professional Portraiture, (or any serious Portraiture) where we might be moving outdoors and/or through many various lighting scenarios – then a reference is invaluable – AND for the reason Colin stated –CONSISTANCY.
In these cases, I usually shoot a Reference Shot at the beginning of every change of Lighting Scenario – for example that would include a Grey Card (at the least – perhaps a Colour Ref Chart too)) and also the skin tone and any fabric which is important (e.g. dress).
And in this case the object of the exercise is Colour Constancy throughout the results (e.g. the Wedding Album)

So, my point is – he requirement for (or the use of) WB and Ref Charts and etc, should be output driven: and not a nonsense “must do” for no reason or because it says so on some website. It is important to know many techniques and employ those, which provide you with the results that you want.

WW

[AB26]

So, my point is – he requirement for (or the use of) WB and Ref Charts and etc, should be output driven: and not a nonsense “must do” for no reason or because it says so on some website. It is important to know many techniques and employ those, which provide you with the results that you want.

WW

Thank you Bill,

Instead of arguing like six year olds, whose daddy is the strongest, this debate is making more and more sense now.

Shooting RAW or Jpg is neither right nor wrong, Auto WB or Manual WB is neither right nor wrong, Aperture priority or Manual mode is neither right nor wrong.

Should it not be the objective of all photographers to capture the mood in that moment in time? Should we not be exploring possibilities of how to capture the mood in that moment in time? What do we, as photographers, need to capture the essence of the mood in that moment in time? Is it possible to capture the essence of the mood in that moment in time?

Mastering camera settings is one step closer to capturing the essence of the mood in that moment in time. Getting the WB settings right, to render the colours correctly in that moment, is one of the most important steps to be able to capture the essence of the mood in that moment in time.
In my own experience I find it impossible to recall the colour and mood in any specific moment I captured an image in. Trying to recall what green the grass was in that moment is impossible. The only “reference” I can recall is pure white and pure black. The problem is that pure white is no longer white, as light changes. How do you recall what shade of yellowish tint was reflected by a white surface when the sun was setting? Capturing that tint as close to what it is in that moment in time is the only true reference you will ever have to make the correct adjustments in PP.

Should we, as more experienced “photographers” encourage newcomers to photography, to disregard camera settings? Advise them to shoot RAW and “fix” it in Photoshop? How often have I not seen this kind of advice being offered? Should we not rather encourage “learners” how to obtain the desired output by mastering in camera settings before resorting to PP? Do we want to teach “learners” to be better photographers or do we want to turn them into computer operators?
Learning to master WB settings, to attain whatever rendition of a scene, in that moment in time, gives the photographer a tool to use that might prove to be of great value in capturing better images than the ordinary happy snap.

In this image, how would Auto WB have rendered the colours? The dress with a strong blue tint and the skin tone more accurate? Do you want the skin tone to be 100% accurate with a mix of LED, candle light and fluorescent? Does the image depict any specific mood in that moment in time?



Yes Bill, agreed 100%, the end result is the ultimate goal. It is the method use to reach the ultimate goal that sort the photographers from the computer operators.

[AB26]

Andre, I'm truly not trying to force any point of view on anyone, and I apologize if it came across that way. I just wanted to be sure that you, and anyone else who might be reading this thread, understand the choice and the consequences. It seems that you do. So you'll get no further argument from me. Only you can determine what's right for you, and I fully support your right to make your own choices. I hope there's no hard feelings, and I'm looking forward to seeing the images that you share with us.

Sorry Arlen, I should have separated that last paragraph differently. It was not aimed at you! My mistake. No reason for you to be sorry.

[xpatUSA]

This paper by Finlayson, Hordley and Hubel concludes that white balancing by estimation of the illuminant (what we do when selecting anything other than AWB) is a superior method compared to AWB.

http://www2.cmp.uea.ac.uk/Research/c...Hub_ICCV99.pdf

In the paper, real-worlders can scroll down past all the formulae and boring facts to see the images that tell the tale.

It seems obvious that, even with mixed lighting or light with a color shift, the best image (most color-constant) is given by the best estimate of the illuminant white point.

Another paper by Viggiano states that better color constancy is achieved by in-camera white balancing rather than on-screen:

http://www.acolyte-color.com/papers/EI_2004.pdf

So, going to extremes, anyone who for example is shooting on a sunny day under green foliage and selects 'fluorescent' WB could be getting it right

[revi]

This paper by Finlayson, Hordley and Hubel concludes that white balancing by estimation of the illuminant (what we do when selecting anything other than AWB) is a superior method compared to AWB.

http://www2.cmp.uea.ac.uk/Research/c...Hub_ICCV99.pdf

In the paper, real-worlders can scroll down past all the formulae and boring facts to see the images that tell the tale.

It seems obvious that, even with mixed lighting or light with a color shift, the best image (most color-constant) is given by the best estimate of the illuminant white point.

Sorry, but that's a bit of an open door:
of course using the WB setting that corresponds to the illuminant gives the best result, as that's exactly what it's designed for...
The problems start when:
1: there is no setting corresponding to the illumant you have to work with (e.g. mixed light sources, coloured reflections like from leaves, or most fluorescent source including LEDs);
2: you don't want a perfectly neutral result.

For the record, the article cited did not try to conclude that the best WB is the one corresponding to the illuminant, the authors were presenting a different method to estimate the optimal correction from the image data (in effect a way to get an optimal AWB).
A quote from the conclusion Ted referred to:

In this paper we have considered the colour constancy problem; that is how we can find an estimate of the un-
known illuminant in a captured scene. We have seen that existing constancy algorithms are inadequate for a variety
of reasons. For example, many of them make unrealistic assumptions about images, or their computational com-
plexity is such that they are unsuitable as practical solutions to the problem. We have presented here a correlation
framework in which to solve for colour constancy.

[xpatUSA]

Sorry, but that's a bit of an open door:
of course using the WB setting that corresponds to the illuminant gives the best result, as that's exactly what it's designed for...
The problems start when:
1: there is no setting corresponding to the illumant you have to work with (e.g. mixed light sources, coloured reflections like from leaves, or most fluorescent source including LEDs)

I wasn't trying to imply that, for every illuminant, there is an exact camera WB setting for that illuminant. Instead, I meant to say that the closest guess gives the most color-constant image. To paraphrase your goodself: of course using the WB setting that [is closest] to the illuminant gives the [better] result

2: you don't want a perfectly neutral result.

I assume that this is a reference to sundown shots or those of models with pallid skin tones or to enhancement of product shots for marketing purposes, etc. My own preference is for best color accuracy in the shot, adjusted in post (not in the camera) if required.

For the record, the article cited did not try to conclude that the best WB is the one corresponding to the illuminant, the authors were presenting a different method to estimate the optimal correction from the image data (in effect a way to get an optimal AWB).

Agreed, but we can not control the AWB method provided in our cameras, so it is almost certain that many of our cameras would do poorly with AWB selected and a viewfinder full of this:

[Geoff F]

Today I had an experience which reminded me that some subjects, particularly flowers, can 'change colour' under different lighting sources.

My subject was a Heath Lobelia which was a nice pale blue when in shadow; but photographing it with flash, or the same species in sunshine, produced a rather purple/magenta hue.

I didn't expect anything different but just had a little experiment.

With correct WB custom settings I was getting a good match to the flower when viewed on my camera screen. But there were two totally different results from what was the same flower species but under different lighting conditions.

In shade, without flash, I had to use a little bit of exposure compensation to get an exact colour match.

Some flowers, like Irises for example, will always present problems by 'changing colour' in different light. I have even brought a problem flower inside and placed it beside my computer screen. But as soon as it came indoors, the colour changed.

[drjuice]

Okay, so what's a SOOC, please?

Thanks.

virginia

[Manfred M]

Okay, so what's a SOOC, please?

Thanks.

virginia

Straight Out Of Camera

[William W]

Okay, so what's a SOOC, please?

Straight Out Of Camera. (i.e. indicating that there is no out of camera post production to the image.)

Also similar, but (as far as my experience is) a much less used acronym: WAM (Without Any Manipulation)

SOOC is used to indicate that the JPEG file is a 'reasonable' visual reference of 'actuality' - and also sometimes 'SOOC' is used for completion purposes / rules.

'SOOC' became problematic almost as soon as it began to be used, because many manufacturers introduced a selection of in camera functionality to adjust the JPEG - for example in Canon there are selection of Camera Styles. It is assumed (at least in the wider circles that I frequent} that 'SOOC' refers to the Picture Style, etc, being set to the Camera's Factory Default


Example of 'SOOC' used in a comprehensive descriptive of an image and a reason for using it:


5D; 24~105/4 IS @ 82mm; F/4 @ 1/5s @ ISO1250; IS ON; M Mode; AWB #593236 JPEG SOOC

In the above image, it is necessary to inform 'SOOC' (in combination with indicating 'M Mode') so that the viewer would appreciate that the exposure represented that which was at the scene - i.e. that the three women's faces were exposed by the P&S Camera's Flash and that the image was NOT post produced to simulate it.

Similarly, in the earlier sample of the peach blush flower 'SOOC' was indicating that the JPEG was a reasonable representation of the scene, because the image was not manipulated in Post Production.


WW

addendum - Thanks Manfred . . . I was still typing the manuscript!

[William W]

Instead of arguing like six year olds, whose daddy is the strongest, this debate is making more and more sense now.

Andre, I am glad this thread makes more sense to you, now, but as you have raised these new matters:
for the record, I did not read any person's commentary on this thread: as 'arguing like six year olds, whose daddy is the strongest'

***

. . . the end result is the ultimate goal. It is the method use to reach the ultimate goal that sort the photographers from the computer operators.

So, if the thread is making more sense - what then do you still remain confused about?

Photographers have always manipulated the Development of the Negatives and then used Darkroom Manipulation. For digital imaging, they use a computer. Most people (even non photographers) make that relationship and make that transition, without confusion.

***

To answer two of your other questions:

In the image of the Bride, I would want the skin tones to be rendered more accurately, as, for that image it is one of the more, perhaps the most important technical feature because of the image real estate that (especially) the face and leading upper arm occupies. Getting the skin tones accurate far outweighs any warm feeling that might be created by the yellow/orange cast, the Bride's facial expression can easily carry that happy, warm mood.

Generally a yellow / orange / red cast used to create warmth works well for the background but for skin tones of we always run the risk of stimulating in the viewer the feeling of a jaundice: this is why many Wedding Photographers will use Flash as Key for the Bride but drag the shutter to allow the Church's Ambient to exude the warmth, where the Flash has fallen off, in the background.

WW

[Manfred M]

Unless you are shooting in a neutral colour studio, it is important to remember that WB will be a bit of a compromise.

Take a picture of a bride in white sitting on the grass under a tree and you will be fighting a green colour cast, regardless of what the "correct" WB is. Correct for the skin tones and you will be getting grass and leaves that look less vivid than they did in real life. Take a bounce flash shot in a room with red walls and ceiling and you will be fighting skin tones that look too red and you will have to dial back the red a bit resulting in proper looking skin tone, but walls that are probably a bit less red than in real life. You might be okay with that, but if you are shooting a commercial shot for Coca Cola, they won't take too kindly that you have good looking skin, but at the expense of getting the brand colours looking "off".

Take a shot on a sunny day out in the snow and get the skin tones correct, and the shadows will end up looking blue.


Getting good colour balance will often mean figuring out what colour balance trade-offs you can live with. As Colin points out, B&W conversions make all these issues go away.

[AB26]

Today I had an experience which reminded me that some subjects, particularly flowers, can 'change colour' under different lighting sources.

Geoff,

I don't think it applies to some subjects only. It applies to all subjects. As the Kelvin temperature of the light changes the colour reflected by the subject will change. And it is not a matter that the colour can change, it does change.

Some of our more technically inclined members will tell you that the eye adapts to the changing colour temperature to see white as white. The camera is better than the eye in recognising the changes in light temperature and is more prone to capturing the hue and tone in that particular moment in time. Therefor the WB settings can be adjusted to adapt to the changing light temperature. I don't think you always want to neutralise the effect of changing light temperature. Sometimes it is better to enhance the effect of light temperature on a subject, hence those warm or cool looking images.

Using the changing temperature of light is one of the great tools in the hands of a skilled photographer in capturing magnificent images. Understanding colour and the temperature of light is probably the most important aspect in understanding the art of painting with light.

I guess you know all of this. I am only explaining it to you to make sure I know all of this.

[SteveF]

Where I struggle with the concept and application of 'correct' white balance is shooting for other people either on spec for sales or contract for promotion etc.

Whilst I know the eye/brain corrects for colour temperature the general public does not. So 'correct' colour temp for me can be either what I think the client wants as Manfred comments about the Coca Cola logo and what I think it should be. A wedding I did with the cerise pink bridesmaids dresses was a right pain for me because like your flowers they changed colour under the north facing shade of the church to the open sunlight out of the church's shadow but would the client understand this? Fortunately the guests photos came out red instead of pink and with a bit of manipulation I aquired a reasonable balance and the client was happy - very happy in fact.

Auto WB was used in the raw format (why I shot raw was due to the camera only being back from Canon about 5-6 weeks before the wedding and I was not sufficiently comfortable shooting jpegs only) and I converted the files in each and every option available to me and none gave the same consistent colour under shade or open sunny conditions.

This wasn't a case where I could let it pass because of the importance of those colours matching the grooms cravat, pocket hankerchief and the bride/bridesmaids flowers. Those files took a lot of work to get a balance both on my calibrated monitor and our office monitors which are not calibrated to simulate the client taking their images to other folks monitors such as tv and pcs etc.

As it turned out the Auto WB images from the raw files on a 'standard' parameter with a 'tone' setting of minus 4 gave the most consistent results. Now the following is not a raw/jpeg dig but some experiments I performed showed the raw files to be more deeply saturated before conversion and the resultant jpeg after. This perplexes me somewhat because to get the jpeg right the raw would have to be even more saturated prior to conversion to get what I wanted. This begs the question that am I seeing on the camera screen the raw before conversion (which I suspect I am) or a correctly rendered jpeg after conversion? Being able to see the image correctly on the screen after exposure is the place and time I would make a decision to alter the camera settings.

Looking into this aspect of what the screen shows at exposure I found a technique that Live View cameras can provide and that's to set the camera on live view and adjust the white balance through the Kelvin adjustment instead of the presets for more finely tuned results. It would be useful for flowers and the like where your subject can get neither bored or able to bill you for more of their time!

[revi]

Geoff,

I don't think it applies to some subjects only. It applies to all subjects. As the Kelvin temperature of the light changes the colour reflected by the subject will change. And it is not a matter that the colour can change, it does change.

Some of our more technically inclined members will tell you that the eye adapts to the changing colour temperature to see white as white. The camera is better than the eye in recognising the changes in light temperature and is more prone to capturing the hue and tone in that particular moment in time. Therefor the WB settings can be adjusted to adapt to the changing light temperature. I don't think you always want to neutralise the effect of changing light temperature. Sometimes it is better to enhance the effect of light temperature on a subject, hence those warm or cool looking images.

Using the changing temperature of light is one of the great tools in the hands of a skilled photographer in capturing magnificent images. Understanding colour and the temperature of light is probably the most important aspect in understanding the art of painting with light.

I guess you know all of this. I am only explaining it to you to make sure I know all of this.

There is something called metamerism. One effect of this is that colours that look the same under one illuminant/light source, can look different under (some) other illuminants. And I'm not sure twiddling the white balance can correct that (i.e. make the colours look identical again).

That might be part of what caused Steve such headaches with his 'Cerise Pink' dresses...

[SteveF]

There is something called metamerism. One effect of this is that colours that look the same under one illuminant/light source, can look different under (some) other illuminants. And I'm not sure twiddling the white balance can correct that (i.e. make the colours look identical again).

That might be part of what caused Steve such headaches with his 'Cerise Pink' dresses...

That's the conclusion I'm coming to with 'absorbent' material more than glossy/shiny materials.

[William W]

A wedding I did . . . files took a lot of work to get a balance both on my calibrated monitor and our office monitors which are not calibrated to simulate the client taking their images to other folks monitors such as tv and pcs etc.

This is a universal problem which many Wedding & Portrait Photographers now face: because of the swing to selling files on a disc, sans print.

I believe that the best answer is a formal showing to the Client of the finished product (the disc) and also a considered mention of how different monitors (especially the home TV) will affect a viewing change.

I sell few "files on disc only": but when I do, the Client signs off on the Product, at the Showing.


WW