Why do we have to change white balance?

[Ron77]

Hey serious question here. How come our eyes see things 'normal' but our cameras freak out if the lighting comes from different sources? I mean, why can't a camera just capture the actual color of everything?

It's weird, it can get the full spectrum of colors but it always shows them different then our eyes see them. .... or do our eyes get it wrong but were just used to it.... I wonder what color things really are, maybe WE'RE seeing things wrong! :eek:

[brucep]

Our eyes "know" what white looks like, somehow. When our eyes are white balanced for a certain situation (the room you're in right now, say) and they look at a photo with incorrect white balance, it looks off-color.

Our cameras are amazing computers, and actually they do a pretty good job if you give Auto White Balance a chance. I use AWB most of the time. When I DO change my color balance in my camera is when I'm dealing with multiple light sources with different color balances.

When I took this photo (http://www.photozo.com/album/showphoto.php?photo=157774&ppuser=7198), for instance, most of the available light was tungsten (screw-in light bulbs), but there was also some daylight coming in from camera right through a window. I lit my subject with a softbox at camera left and a tiny softbox above and behind her (a bit to camera left, behind her). In these softboxes were Canon 580EX flashes with CTO (amber) gels on them to match the tungsten lighting. I set my camera to Tungsten white balance. That made those screw-in bulbs and my flashes look like white light (the same color). It also made the daylight even MORE blue, but I kind of like the blue kicker coming from that window light camera right.

WARNING - WARNING! Be sure to turn you camera BACK to AWB when you're through doing something strange like this!

[Ron77]

That shot came out great!


Man I know, I've messed with white balance on my camera, forgot to change it then had a whole slew of blue pics lol

So our eyes recognize white. I guess our brain knows what white is and can adjust then? I use auto most of the time with my cam too but found that when I'm outside, daylight works better if people's faces are in the photo. Otherwise they end up too 'magenta' looking. What drives me nuts is if I shoot in raw and try to decide what white balance looks 'right' when I have no reference in the photo to know for sure. Oddly, if you put the dropper on something that IS white in real life, sometimes it makes the photo real amber. But yet, my eyes see everything normal. one thing that's hard for me is shooting in tungsten light, if you pick that for a white balance, it takes away all the yellowish light, but my eyes see some yellow. Auto is super yellow, tungsten is too neutral.

I think instead of less noise, or higher megapixels, they should make a camera that does white balance properly :)

[Landis]

Ah, Ron, light is a finicky source. When you are outdoors on a sunny day, you get all sorts of BLUE that is reflected from the sky and it is warmed by the rays of the sun. Step in the shadow of a building or tree, and you are getting BLUE light from the sky coming in with no warming sunlight. Tungsten lights are very warm, florescent lights much cooler, and an electronic flash different from any of the above.

Bruce is right: Our brains make for great WB fixers!

If you make a fine art print. You need to know WHERE it's going to be hung so you can balance the color so it will look right under the light where it will hang. Where I do my color printing, I don't have a special light for viewing like most pro printers have, but I do have a skylight and know where to place my prints so I can look at them to get pretty close to the best light for viewing prints.

[JimL]

Actually we do NOT see colors correctly as individuals. We see them relatively correct IF we :
1. View them in a continuous light source or
2. View them in intermittent light sources which can be calibrated to (or close to) each other (depending, of course, on the degrees of separation of the subjects color from its surroundings).

Example: If you place a primary color cone in noon sunlight and you have a row of various other colored cones which include a cone the same color. Now someone asks you to go pick out the identical colored cone most would have little trouble doing so.

If, however, you stand with the original color cone in dim light (not colored but deep shade for instance) and then you go out to the noon sunlit row of cones it will be much more difficult for you (again depending on the degrees of separation of colors) to pick out the identical color.

This has to do with the way the rods and cones in our eyes trade viewing duties based on the available light.

This just means that depending on viewing conditions our eyes may not be better than the camera sensor when choosing a white balance to get "proper" color.
JimL

[AJ]

Ron - actually our cameras see (and record) the color of light more accurately than our eyes see the same light color. Our brains make the adjustment so that we see whites as white, blacks as black and everything in between under different color lights. For the most part, our cameras do a pretty good job adjusting the white balance but there are times when the camera needs some help from us. Mixed lighting conditions and flickering fluorescent lights are problematic. I set a custom white balance when I know lighting is going to be a problem. This usually happens when I'm shooting under older fluorescent lights. They cycle and throw off different colors during the cycle so you can get good white balance on one shot, yellow on another, etc. and even custom white balance settings aren't going to help that.

[Ron77]

If you make a fine art print. You need to know WHERE it's going to be hung so you can balance the color so it will look right under the light where it will hang. Where I do my color printing, I don't have a special light for viewing like most pro printers have, but I do have a skylight and know where to place my prints so I can look at them to get pretty close to the best light for viewing prints.

Oh man your kidding, you have to know what light will shine on your prints? Is that why people use art lights for paintings, not only to light them but to make sure the colors are right?


Actually we do NOT see colors correctly as individuals. We see them relatively correct IF we :
1. View them in a continuous light source or
2. View them in intermittent light sources which can be calibrated to (or close to) each other (depending, of course, on the degrees of separation of the subjects color from its surroundings).

So in reality then, we just think that were seeing things normal and were trying to get the camera to capture the innaccurate but 'normal' colors we see then?


Ron - actually our cameras see (and record) the color of light more accurately than our eyes see the same light color. Our brains make the adjustment so that we see whites as white, blacks as black and everything in between under different color lights. For the most part, our cameras do a pretty good job adjusting the white balance but there are times when the camera needs some help from us. Mixed lighting conditions and flickering fluorescent lights are problematic. I set a custom white balance when I know lighting is going to be a problem. This usually happens when I'm shooting under older fluorescent lights. They cycle and throw off different colors during the cycle so you can get good white balance on one shot, yellow on another, etc. and even custom white balance settings aren't going to help that.

Interesting, I would like it though if my camera recorded exactly as how I saw it. I'm noticing the biggest problem with outdoor light and human faces on auto white balance, I hate any magenta tones. I never noticed it before until I took some shots of my wife outside with my new 50mm 1.8 and then played with white balance after, to make it look just right I picked 'daylight' in post processing and then had to cool the temp just a bit. Then I wondered how many other photos were off like that, it could drive ya crazy trying to get it right :)

[JimL]

If you use DPP from Canon you can make a setting that will apply each time you pull photos in from your camera. You can also do that in Lightroom. In my 5D I can also adjust the settings in my camera and save it so the camera adjust what it sees to my preferences. In any of these methods you only have to adjust it once and the software or camera will continue making adjustments automatically until you change again.
JimL

[Ron77]

I've played with that, maybe I'm being to anal about getting it how I wanna see it, but I noticed, for example, in Lightroom that when I choose a white balance, it's not always the same temp number. I guess really then, a person has to tweak a bit if they want it a certain way. Which still makes me say I hate white balance lol

[arezai85]

Good discussion. Thanks
as your writing I understand the skill of WB is something we should try again and again to know our camera and choose good WB in different condition.

Ali

[Ron77]

You know what amazes me and I think I posted about this like a year ago, is when you watch a TV show and their outdoors and the white balance looks spot on all the time. Those movie cameras must have a great processor in them for that.

[Landis]

Oh man your kidding, you have to know what light will shine on your prints? Is that why people use art lights for paintings, not only to light them but to make sure the colors are right?

Ron, if you take any print and hold it under different light sources, it will look completely different. When I took my printing workshop a number of years ago, we took 3 identical prints. They had 3 small light booths with florescent, tungston, and daylight bulbs in them. The prints all looked totally different.

If some professional photographer is going to hang a show of their work and have it all printed for the show, the first thing they will ask the gallery is what lights they have and print accordingly.

Life isn't always as simple as we think it is.

[Skippy]

That was a good question Ron and the answers are so varied and more than some of us will ever remember. :confused:

But I agree our eyes don't always see correctly. If you go out in the moonlight, they will see very little color, if any. If you are out in the middle of the blazing sun at noon in the desert you won't see everything either. Then there is everything in between and some.

I use the auto WB and it is fine most of the time, but not always. I just find it an easier place to start if it needs changing.

Skippy

[Landis]

I'm with Skippy on using AWB most of the time. About the only time I change it is when I am using my flash. As I shoot RAW all the time, I use the Eye Dropper in RAW converter in PS CS4 to get the right balance......which I may then change a little to get the image the way I want it. This is one subject I really don't fret about.

[Ron77]

Skippy- Yes I totally know what you mean about darker lighting like the moon, and agree this is very interesting.

Landis- I had no idea people printed photo's differently for different lights, it seems like your photos should be printed 'normal' and they should have to use the right lights..
Hey question, if a person adjusts white balance on a calibrated monitor, then just prints that photo, what lights WILL that photo look right under?

I used auto all the time too, but I can see I'm going to have to tweak it a lot more. I think why I'm just noticing this is my previous camera, the Nikon, was auto balancing really perfect outdoors, but my new camera isn't getting it right outside. But auto with pop up flash is perfect on this new camera