Custom White Balance - Grey or White?

[dfuccillo]

When custom seeting the WB on my canon 10D is it best to use a white or grey card? Or does it matter?

Thanks

[gasrocks]

White. I can tell what a white card looks like (as opposed to off-white, dirty white, etc.) 18% is hard to judge with the "naked" eye. If you balance off the wrong thing - you get wrong answers = off color pix.

[scottbergerphoto]

Use a white Mr. Coffe coffee filter over the lens.

[jimsolt]

When custom seeting the WB on my canon 10D is it best to use a white or grey card? Or does it matter?

Thanks

Is it called white balance or is it called gray balance? There will be those who say gray is fine and they may be right. 18% gray is teriffic for setting exposures. A whole lot of people confuse exposure and white balance. They are different ajustments. Some cards come with one side gray and the other white. I always ask the gray card white balance advocates, "Why is one side of the card white?" My own opinion is the white side is for white balance, the gray side is for exposure. A card with white, gray and black stripes is teriffic -- for exposure. Use the white stripe for white balance.
Those with a different opinion will show you some fabulous pictures made with white balancing with a gray card. Then you will get the view that it's all unnecessary if you shoot RAW. However, I've yet to hear a really good photographer say it isn't best to start with as much being right as possible.
The critical point with white balance is that it is a measure of the color of the light -- not the measurement of the subject material. It will affect how the subject looks, but it is telling the camera what color the light is and based on that information, the camera shows you what things look like.

Jim

[Adam Hicks]

You can control white balance as easily on a grey card as a white card. As long as it's pure grey it will reflect ambient color as well as white and the camera does a fantastic job of adjusting with it. With the added benefit of being able to meter from the grey card, a white card seems like a waste of money to me.

Then there's the Expodisc which does a cool job on both fronts, but costs way to much IMO.

Then again, yes, shooting RAW is the best option to me. As long as your exposure is correct and nothing is blown, minor white balance variations are easily fixed. Plus, using a grey or white card to set WB is all well and good if you stay in the same place, in the same light conditions. If you move around it's going to be a big pain in your butt :)

Adam

[BobbyC]

I've always used a grey card and it works perfectly. I know some that use white and it works too. Just make sure you get a pure white or 18% card as was mentioned. Mine are made by Kodak. I like the grey because I can also use it for exposure if needed.

[robertwgross]

The trouble with a pure 18% gray card is that you must depend on the manufacturer that the card is actually pure and has no color tint to it. On the other hand, most people can eyeball a white card and tell how pure it is, especially when compared to other white cards. Further, in some cases you want to use a slightly pastel version of a white card to set up a skewed custom white balance. Your eyeball can tell the pink version versus the pale blue one. But, if this were in the gray tone, I think it would be much more confusing.

---Bob Gross---

[PhotosGuy]

This is in the Talk About Photography sticky "Photography Tips and Tutorials List" ;-)

Gray Card…White Paper. What’s best?
http://photography-on-the.net/forum/showthread.php?t=58677

[Marvinspu36]

I use a Delta 18% gray card. I get excellent, reliable results with this method. The 8"x10" cards are less than $15 for 2 cards. Canon recommends using an 18% gray card, at least for the 20D. The following quote is from the Canon 20D owners manual, page 52:

"Instead of a white object, an 18% gray card (commercially available) can produce a more accurate white balance."

If you search this forum for "white balance" or "gray card" you will find a lot of information on this subject.

In the end, it really depends on if you are happy with the way your pictures are turning out.

I like the gray card because I know it is constant. Also, it is much easier to overexpose a white card, which will throw off your white balance.

[PhotosGuy]

Also, it is much easier to overexpose a white card, which will throw off your white balance. That's true, but this doesn't have to be hard. The white 'card-paper' has an advantage in low light situations which is explained in the data sheet that came with my card - it's easier to get a reading since it is brighter.
Take a reading & pic of the white subject & you'll see the histogram is concentrated in the middle - just where you want it. Do your WB. Close down ABOUT 2-1/3 stops & take another shot. Chimp the exposure so it almost touches the right side. Done in less than a minute.

[Az2Africa]

I use the Expodisc and I am very happy with the results. But as said above, it is more expensive than it should be. It is designed to snap on to the front of the lens and comes in various sizes. I recommend that if you want one, buy one for the largest lens you have and just hold it over the smaller ones. I paid $109.00 for mine and have not regretted the purchase.

Cheers,
Terry

[PhotosGuy]

I paid $00.00 for mine and have not regretted the purchase.

[ron chappel]

The camera simply doesn't know the difference between white ,grey or black-when you take a pic for CWB it will expose them all to middle grey anyway
But if using a home made card/object it's best to use white rather than grey or black for the reason stated above-it's much easier to guess by eye wether the card/object really is white

When i first started trying CWB i used several white/grey items around the house and still use one of them-a white plastic container.It gives excellent results
As i don't need CWB outdoors i've never bought a proper card

[chtgrubbs]

Gray Card, please. A Kodak gray card, please. Kodak cards are made to strict tolerances. White usually isn't really white. You can go to a frame shop and see at least a dozen different shades of "white" matboard. You can go to an office supply store, buy six different brands of white paper and they will all be different shades of white when measured with color reflection densitometer.

The best solution is a MacBeth Color Checker.

[blue_max]

A tip I heard from an old pro (photographer :rolleyes: ) was that if you focus on the palm of your hand that is 18% grey - regardless of whether you were of a different skin colour.

All I can say is try it and see. If it is under or over you can allow for it, but chances are you will have one with you when you most need it - and carry a spare!

Graham

[gasrocks]

The palm of my hand is 1/2 an f/stop diff than a gray card. That is for getting proper exposure - has nothing to do with focus or white balance.

[DavidEB]

If you shoot a white card, and underexpose it, it will be gray. If you shoot a gray card, and overexpose it, it will be white. If you use something that looks white to your eye to set the white balance on your photo, then that will be white in the finished product. If your white paper looks white to you, then it's fine to use for setting balance, even it has little bits of color in it. If your gray card looks white to you, then use that. When I shoot snow scenes I use the snow to set white balance and when I shoot hockey I use the ice (out-of-focus, exposed to center the histogram). Those are the targets I want to look white in the finished product.

The big mistake I made in my first months with a digital SLR was to shoot my white balance object at an exposure that made it white (that is, at the right of the histogram).

[robertwgross]

For those who would like to kill two birds with one stone...

Get the National Geographic Photography Field Guide. Mine has a 2001 date on it, but there may be something newer.

Inside the front and rear covers, there is a gray card. Pure 18%. Since these are inside the covers, they are not too likely to be left out in the sun to fade.

---Bob Gross---

[jimsolt]

If you shoot a white card, and underexpose it, it will be gray. If you shoot a gray card, and overexpose it, it will be white. . . .
The big mistake I made in my first months with a digital SLR was to shoot my white balance object at an exposure that made it white (that is, at the right of the histogram).
White Balance is not the same thing as exposure.
Jim

[robertwgross]

White Balance is not the same thing as exposure.

Several people here have not caught onto that fact yet.

---Bob Gross---

[Jaymz]

Just to make sure I understand this correctly, since I am new to all of this, White Balance is used to make sure your colors come out correct (or as you want them to) and exposure is, roughly, the amount of light the film or CCD sensor recieves. Am I understanding it correctly?

[DavidEB]

Jim, Bob --

Your comments make me think I was not sufficiently clear in my post, and I apologize if I have caused you to be post needlessly.

To make my point more plainly, there is no difference between a white card and a gray card IF the exposures are set so each is "properly" exposed - eg, in each shot the histogram shows a single bar in the center. Try it -- in M mode, shoot a piece of plain white paper with the exposure set so the meter shows correct exposure, then turn the exposure up about 2-3 stops and shoot your gray card -- they will look the same. You will get the image with either a white object or a gray card, assuming you have set the exposure properly. Then when you use that image to set white balance, it won't matter whether the original object was white or gray.

The mistake comment refers to using a white balance object shot in a way that it is overexposed, that is, pixel values of 255-255-255 for each of 3 colors. All that matters for your white balance calibration shot is that the image not be completely blacked out or completely whited out.

Thank you for trying to set me straight, I know you meant well.


kind regards,

[jimsolt]

Just to make sure I understand this correctly, since I am new to all of this, White Balance is used to make sure your colors come out correct (or as you want them to) and exposure is, roughly, the amount of light the film or CCD sensor recieves. Am I understanding it correctly?
By George, I thnk you've got it! White balance tells the camera what color the light is and serves the same function as different types of film (daylight, tungsten, etc.) did and you have hit it right on the money with exposure measuring the amount of light that hits the sensor.
Jim

[jimsolt]

Jim, Bob --

Your comments make me think I was not sufficiently clear in my post, and I apologize if I have caused you to be post needlessly.

To make my point more plainly, there is no difference between a white card and a gray card IF the exposures are set so each is "properly" exposed - eg, in each shot the histogram shows a single bar in the center. Try it -- in M mode, shoot a piece of plain white paper with the exposure set so the meter shows correct exposure, then turn the exposure up about 2-3 stops and shoot your gray card -- they will look the same. You will get the image with either a white object or a gray card, assuming you have set the exposure properly. Then when you use that image to set white balance, it won't matter whether the original object was white or gray.

The mistake comment refers to using a white balance object shot in a way that it is overexposed, that is, pixel values of 255-255-255 for each of 3 colors. All that matters for your white balance calibration shot is that the image not be completely blacked out or completely whited out.

Thank you for trying to set me straight, I know you meant well.


kind regards,

It makes no sense to speak of white balance in terms of 255-255-255. It doesn't apply. Light balance refers to the color of light which is expressed in degrees Kelvin. Those are expressed in terms of 3200K, 5300K, 9000K, or sunlight, shade, cloudy, etc. In film they were dealt with by types of films (daylight, tungsten, etc.), or by filters either on the lens or on lights or windows that modified the color of the light hitting the scene. You could use daylight film if you used blue gels on tungsten lights. They work at any intensity. They refer to colors of light, not units measuring intensity. The one place you could/can run into some intensity problems is with a tungsten light source that is dimmed by a rheostat. Then not only the intensity changes, but the color as well, but they are still 2 different things requiring 2 different ajustments.

I did indeed mean well, and I still mean well. Be that as it may, white balance and exposure are not the same thing.

Jim

[DavidEB]

White balance and exposure are definitely not the same thing, but it is very helpful to understand how they interact. In taking the photo which you use to set custom white balance, or which you use in post-processing to pick your white point in software, it doesn't matter if the original object was gray or white, as long as you got the exposure right when you take that shot. It also doesn't matter what your white balance was when you took the calibrating shot. All that matters is you expose it correctly (there's a wide lattitude here - anything less than a blown-out image will work).

The digital camera records information in binary. In discussing color in digital, RGB values are the lingua franca. A single pixel is a set of 3 values (r-G-B), ranging from 0 to 255. If you overexpose your white balance object, and get pixels which are blown out (255-255-255) then they are useless for setting white balance. Try it -- take a photo of something green, but overexpose it so that it's blown out (to the far right of the histogram, and blinking on the review screen). It will look white in the image you took, even though it's green in reality. If you use it to set white balance, your resulting pictures will be off.

If you want to set white balance so that a certain part of your picture looks white, then I recommend using that object as your target in a shot, epxosed so it is not blown out, and set the white balance off that. Far more straightforward than gray cards.

[hmhm]

A white card reflects all colors of visible light about the same amount, and reflects most of it.

A photographic grey card reflects all colors of visible light about the same amount, and reflects only 18% of it.

A card that has a "tint" to it would reflect some colors of light better (as in, more of it bounces back, and less is absorbed) than others.

When we do white balance, we're taking a sample of the ambient light to see what color tint it has. For instance, incandescent light has a yellow/orange tint, while flourescent lights tend to have a greenish tint. By giving the camera a sample of the light, it can see what color the light is, then when it takes a picture of a real subject, and sees the ambient light reflected off of stuff of different colors, it can adjust the reflected colors to compensate for the tint of the ambient light, effectively making the picture look like it was taken in "white" ambient light.

Now, when taking that "sample", we need to bounce the ambient light off of something that doesn't change the color of the light, we need something with "neutral" reflective properties. Per the definitions of a grey card or a white card, they both have the necessary neutral color properties.

So as long as your white card is truly white, and your grey card is truly grey, they both have identical properties as far as white balance goes, namely they both reflect the ambient light without changing its color.

For our purposes, we want to use the camera's metering system to expose the "sample" shot. Whether you're shooting a grey card or a white card, you should end up with a "picture" that looks like a grey card, as the camera will expose the white card shot less. This is fine. Your goal in taking the sample shot isn't to end up with an accurate picture of a white card, it's to sample the light, so there's no need to apply exposure compensation to a white card shot just to make it look like a white card (in fact, that's counter-productive). If you don't (wrongly) apply exposure compensation, then it should be no more likely to over-expose a white card than a grey card. If anything, a white card might be a little better for use in extremely low lighting, near the limits of your camera's metering system, but I doubt very many of us ever operate near those limits.

Don't worry about whether its called "white balance" or "grey balance". White is bright grey, grey is dark white, they're the same thing as far as color is concerned. The camera sees a grey card in bright lighting as identical to a white card in dimmer lighting.
-harry

[jimsolt]

White balance and exposure are definitely not the same thing, but it is very helpful to understand how they interact.

I do understand that. They don't interact. They both affect the picture as does focus, the lens used, motion of the subject, the size of the sensor and and on and on and on, but they don't interact.
As an aside, white balance has nothing to do with 1s and 0s and digital as opposed to analog. The color of the light remains the same and has the same influence on the picure whether or not your camera does arrays of Rs, Gs, and Bs or Kodak, Velvia, or Ectachrome, still or motion picture film, still or TV digital pickups, etc.
When someone asks what time it is, the answer does not involve how the watch works. When you buy a photoflood lightbulb, the salesman does not ask if your camera is digital, or what f stop you will be using. He sells you a bulb that is rated at 3200K.

Jim

[DavidEB]

Harry -

thank you for explaining this very clearly.

[Jon]

It makes no sense to speak of white balance in terms of 255-255-255.

Except that CWB works by assuming that the subject should be giving equal levels of R, G, & B on the sensor and uses the corrections it derives from the actual recorded differences to adjust every other pixel in the image. It doesn't function directly as a colour temperature meter, except possibly secondarily and through a recorded EXIF field. Exactly how those deviations from a 128-128-128, or 255-255-255, or whatever the actual exposure level may have been, setting relate to the light temperature in Kelvins isn't important for in-camera white balancing, although if you choose to use a colour temperature meter to set your specific white balance, there's undoubtedly an algorithm that can be/is used. But CWB doesn't need to know what the colour temperature is; just that your subject is truly neutral.

And the eye is not reliable as a judge of what's neutral. For instance, many papers contain UV brighteners, so that neutral white paper you selected by comparison with three other sheets of paper under your desk lamp (2900 K) will almost fluoresce when you bring it out into a strong UV source, like a sunny day, thus giving a strong colour imbalance. That's why using a commercial, neutral, grey card is preferable. In fact, it's what Canon is currently recommending.

[ed2day]

White Balance is not the same thing as exposure.
Jim

That's true. But a bad exposure can throw off your attempts at a custom white balance. Which is much easier mess up with a white card than a grey card if you're not filling the frame with the card. That's one reason I use a grey card, the other being that I only need to carry one card. Using a calibrated grey card is every bit as straightforward as using a white card, maybe moreso since you don't have to watch overexposure. The only argument I've heard here for using a white card that makes sense to me is that it can be used in lower light conditions.

[kendp]

I had a problem with white balance this morning and in the process of trying to resolve it, I discovered the custom setting.

My camera is a Canon SX10IS.

Do you shoot a white card and set the custom white balance once, or do you have to do this in each situation where the light source is different?

[Jon]

You need to set a new custom white balance every time your lighting changes.

[kendp]

Thanks for quick reply, Jon.

After setting the white balance, do you keep the camera in custom to take the shot? I assume you do, but want to double check that.

[Jon]

Yes. If you move the WB setting from Custom, you'll be using whichever one of the preset WBs you shift to.

[kendp]

Thanks again. That is what I thought.

Maybe you can help me with this question. This morning when having trouble and trying all the preset settings, I found the custom setting. When I selected it, it seemed to indicate that the custom setting could be changed by pushing DISP. So that I what I did,and each time I pushed DISP, I got a different white balance. As I pushed, I checked what I wanted to shoot with the view finder and screen. I kept pushing DISP until I got what I wanted, then took the shot. They came out fine.

The camera manual says nothing about this, it only talks about shooting a white sheet.

Any idea what the camera was doing each time I pushed DISP. All I know is that none of the preset settings helped me, but pushing DISP until I got what I wanted did.

Add on:

I just took another look. When I click on Custom I get {DISP.] Evaluate white bal. Each press of DISP changes the white balance. Though the manual says nothing about this, it looks like the camera is giving you the opportunity to find the white balance best for that shot. Does that sound right?

I know that is what happened this morning. I got rid of the yellowish cast by enough presses of DISP and ended up with a photo that showed, correctly, that the walls and floor tile were white.

[Jon]

It's suggesting that you use a white sheet (although a neutral grey target will also work) so you can set a white balance. If you were pointing the camera at random parts of your scene and pressing "DISP", you were telling the camera that "whatever is in front of the lens right now is white - so set a white balance from that". You were getting variations because the different parts of your scene were different colours, and the camera was trying to adjust things so they looked white or grey. If you were pointing at a green tree, the camera would make the whole scene magenta (as it tried to cancel out the green). If you were aimed at a yellow pad, it'd shift things blue while trying to cancel out the yellow. Try it - find several brightly-coloured objects, set a CWB from each of them and see what happens to the rest of your scene. Then use a sheet of white paper and look again.

[kendp]

Good suggestion, that is what I will do

[kendp]

My experience today seems to indicate that just focusing on a white paper imay not be sufficient.

This morning I was trying to take a photo of something in the office and was seeing an orange cast in the view finder and monitor. I focused on a white sheet of paper and noted that I wan't seeing pure white, the color of the sheet of paper, so I put camera on WB Custom, filled the frame, and pressed DISP, as required with my camera. I then focused on the object and found that the orange cast was reduced, by color still not correct. The object happened to be very near a counter that was a beat-up white, so I focused on it and pressed DISP. I then focused on the object and the color was correct.

[Hermeto]

My experience today seems to indicate that just focusing on a white paper imay not be sufficient.

This morning I was trying to take a photo of something in the office and was seeing an orange cast in the view finder and monitor. I focused on a white sheet of paper and noted that I wan't seeing pure white, the color of the sheet of paper, so I put camera on WB Custom, filled the frame, and pressed DISP, as required with my camera. I then focused on the object and found that the orange cast was reduced, by color still not correct. The object happened to be very near a counter that was a beat-up white, so I focused on it and pressed DISP. I then focused on the object and the color was correct.

Huh?! ???
Display, focusing?
I admit, you got me confused totally, but this doesn’t seem right at all..