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OK folks in the last 24 hours I have been ripped for not reading my manual on here. Because, I did not have one I went out and got one. Also, I grabbed a 18% grey card.

Since yesterday, I have learned how to custom white balance, How to manualy adjust the shutter and aperature. I have learned how to adjust the meter towards zero to gain proper exposure. I have learned how to access the DISP and view all the setting's for hat shot.

I am using a flash in a room with some Tungsten lights behind me. I am shooting plastic molded grocery cart for a baby full of red, blue, yellow & green. ( I assume just regular lamps are Tungsten)

QUESTION 1:
When I white balance and review the gray card photo. I think I need to only use a shot that has a even RGB distribution. I understand that exact is nearly impossible. However, I have had several that has the red shifted further to the right and blue to the left with the green in the middle.

To me this seems wrong and not a good setting to use. It seems like this occurs if I get a gray shot that is not even in color from the flash.

QUESTION 2:
When I shoot and review the photo the object seems fine. However, the items in the back ground have a redish/orange tint to them. Reviewing on the DISP the red is shifted to the right.

Is this from my white balance? I think it is..so I worked in until I got the best balance I could. (Histogram looked dead on even)...But I still had the color shift in the photo.

Auto whitebalance was very similar.

So I then switched to the Tungsten setting and all turned out good. The histogram was very even and the redish tint was gone. (All whites are white)

I thought the custom white balance fixed this very reason?? This is why I got the card I thought.

Is it possible if not probable that because the lighting is fading behind the target and getting darker and the object does not have any direct light that it gets this redish look. Even the white around my fireplace is yellowish.

QUESTION 3:
Should a photo that is properly exposed and lighted, with the a custom/proper white balance have a similar RGB histogram. What is optimal? I thought equal distribution was best, but I am struggling to obtain that.

I appreciate all possible support.

As always, posted examples help a lot in understanding what is going on.

Here are a couple of points for you to consider.
If your grey card shot has even RGB histograms, that means the light illuminating it was white, and no adjustment is required. In practice, that does not happen often. You take an image of a grey card, and it does not have a balanced RGB histogram. That is because the light is not white, which is why you are doing the white balance exercise in the first place. Use the unbalanced image to set the custom white balance. That's how the system works.

For your question 2, bear in mind that the intensity of light drops off with the square of the distance. Your subject, probably the nearest thing to the flash, is receiving most of its illumination from that flash. The background, being much further away, is receiving far less illumination from the flash, and more from the ambient tungsten lighting. That is probably why the background has a warmer reddish tint. There is no way to correct for multiple light sources with different colour temperatures at the time of shooting (other than eliminating them or altering their colour). No white balance setting will help.

LOL I hope you can relate...I know what you are saying. I used all my batteries tinkering with all this stuff. I need to get extras.

xarqi wrote in post #4901031
As always, posted examples help a lot in understanding what is going on.

Here are a couple of points for you to consider.
If your grey card shot has even RGB histograms, that means the light illuminating it was white, and no adjustment is required. In practice, that does not happen often. You take an image of a grey card, and it does not have a balanced RGB histogram. That is because the light is not white, which is why you are doing the white balance exercise in the first place. Use the unbalanced image to set the custom white balance. That's how the system works.

So based on this, I don't need to worry if the RGB Histograms are completely out whack because the Camera is measuring it taking that margin and making the proper adjustments? Correct?

Based on this. Does it seem reasonable that the when I select the CWB to the Tungsten setting that this is effecting the back ground while the flash is exposing the targeted image? Thus giving me a better look. My CWB is with the flash near the target. I did notice the back used at the target for with the CWB was fine.

ggodwin wrote in post #4900876
QUESTION 1:
When I white balance and review the gray card photo. I think I need to only use a shot that has a even RGB distribution. I understand that exact is nearly impossible. However, I have had several that has the red shifted further to the right and blue to the left with the green in the middle.

To me this seems wrong and not a good setting to use. It seems like this occurs if I get a gray shot that is not even in color from the flash.

Not sure what you are asking. But you need to create the custom white balance in the lighting that you are taking the shot. I never look at the histogram for white balance. Mainly because I use RAW, but it shouldn't matter if you shoot in JPEG. But I must say, to get perfect white balance in camera, it much more difficult and takes more time. Light temperature changes too often with tungsten, florescent, flash, daylight, mixed...etc. If your images require correct white balance all the time, I would suggest RAW.

ggodwin wrote in post #4900876
QUESTION 2:
When I shoot and review the photo the object seems fine. However, the items in the back ground have a redish/orange tint to them. Reviewing on the DISP the red is shifted to the right.

Is this from my white balance? I think it is..so I worked in until I got the best balance I could. (Histogram looked dead on even)...But I still had the color shift in the photo.

Auto whitebalance was very similar.

So I then switched to the Tungsten setting and all turned out good. The histogram was very even and the redish tint was gone. (All whites are white)

I thought the custom white balance fixed this very reason?? This is why I got the card I thought.

Is it possible if not probable that because the lighting is fading behind the target and getting darker and the object does not have any direct light that it gets this redish look. Even the white around my fireplace is yellowish.

Your flash has a different temperature than tungsten lighting. When shooting with flash, your foreground will most likely be lit with the flash, then there is a considerable flash dropoff. If your exposure captures the ambient lighting, which I would assume is tungsten, then your background light temperature will be tungsten. The only way around this is to gel your flash with a filter on your flash to match the different light temperatures. Or, photoshop is possible to balance the lighting.

ggodwin wrote in post #4900876
QUESTION 3:
Should a photo that is properly exposed and lighted, with the a custom/proper white balance have a similar RGB histogram. What is optimal? I thought equal distribution was best, but I am struggling to obtain that.

Do you mean custom vs. proper white balance? Again not sure what you are asking. If you custom is made towards proper, then the histograms should be the same.

I think you are thinking too much with the histogram. I use it only to see if I am getting a proper exposure (eg. over/under exposure). Histograms can look quite different in various scenes. With some more to the right/left, dips and valleys in certain places. You can't control how they come out, they just are (based on the scene you are capturing). But you can control the shift of the histogram through different exposures.

ggodwin wrote in post #4901072
So based on this, I don't need to worry if the RGB Histograms are completely out whack because the Camera is measuring it taking that margin and making the proper adjustments? Correct?

Yes - that's exactly how it works. You show the camera something that looks maybe blueish to it because of the light, but tell it that it is really a neutral grey, so the camera subtracts that blue (or whatever) from images taken with the CWB

Hold on a moment - "tungsten" is not a custom white balance, it is one of the standard ones. A custom white balance is when you use a neutral image to set the WB. I'm not sure if we are talking about the same thing here. If you mean setting the WB to tungsten, then the background should look OK. The flash exposed subject will look bluer than it should.

You are exactly correct and come to think of it the image in the foregraound was blueish....

Since this thread was made I have been lying in bed pondering this question. I finally concluded that my white balance was only impacting the target because I used a flash with that custom white balance.
It it a safe practice that shooting with multiple light sources (temps) that I will always have this issue? ...or is it because I has such drastic fluctuations in the two temp's created my issue. The background was actually pretty dim. Basically across the room about 15'with just two 75w lamps behind me shooting.
LAST QUESTION: (I hope)
When I review the photos/Histograms after the shoot and the RGB's are not of a similar shape and/or they are not adjusted in the "x" axis like each other.
Is this a problem. I thought the Camera would make this adjustment...or is this just another issue with the multi light sources.
BTW - I am overthinking this stuff but If I don't I wont understand a thing....

ggodwin wrote in post #4901611
It it a safe practice that shooting with multiple light sources (temps) that I will always have this issue? ...or is it because I has such drastic fluctuations in the two temp's created my issue. The background was actually pretty dim. Basically across the room about 15'with just two 75w lamps behind me shooting.

Temperature of flash is much closer to daylight (sunlight), so shooting in that won't create problems for you. Sunset is a whole different story. Without seeing the pictures, what settings you shot at, it is hard to say how much ambient light went into the photo.

You don't always have to create perfect white balance (foreground and background). Most critical are skin tones (so you may give that a priority). Most people don't mind overly warm (orange) skin tones, because it is sometimes natural in what we see. But if you photograph someone under florescent lighting and skin tones comes out all green, then you will have some serious issues with the photos. But it all boils down to subjective tastes. It is good to know what is "correct", but it isn't a rule.

ggodwin wrote in post #4901611
LAST QUESTION: (I hope)
When I review the photos/Histograms after the shoot and the RGB's are not of a similar shape and/or they are not adjusted in the "x" axis like each other.
Is this a problem. I thought the Camera would make this adjustment...or is this just another issue with the multi light sources.
BTW - I am overthinking this stuff but If I don't I wont understand a thing....

Not sure what you mean. You might want to illustrate with some diagrams. If you haven't visited the page below, go ahead as that really helped in my understanding of the histogram. Although I know you are referring to the RGB histogram, but I think you need to have a good grasp of the luminance histogram first. And seeing as you said in your first post that you were just starting to understand all of this, it will be a good start. http://www.luminous-landscape.com …standing-histograms.shtml

ggodwin wrote in post #4901611
about 15'with just two 75w lamps behind me shooting.
LAST QUESTION: (I hope)
When I review the photos/Histograms after the shoot and the RGB's are not of a similar shape and/or they are not adjusted in the "x" axis like each other.
Is this a problem. I thought the Camera would make this adjustment...or is this just another issue with the multi light sources.
BTW - I am overthinking this stuff but If I don't I wont understand a thing....

This is entirely normal. The only way that the histograms for all colour channels would be identical is if there were exactly the same number of pixels in the image with the same intensity for each of the colours. That is extraordinarily unlikely in a natural scene, and that is why a solid neutral grey card is used to set white balance.

ggodwin wrote in post #4901611
LAST QUESTION: (I hope)
When I review the photos/Histograms after the shoot and the RGB's are not of a similar shape and/or they are not adjusted in the "x" axis like each other.
Is this a problem. I thought the Camera would make this adjustment...or is this just another issue with the multi light sources.
BTW - I am overthinking this stuff but If I don't I wont understand a thing....

The three histograms should look roughly identical only if you photographed a grey card that entirely filled the frame and the camera was properly white balanced for the light source. In a normal picture there are millions of colors. Each one is a different combination of the RGB primaries, so it's inevitable that the histograms will be different. If there are areas where one of the primary colors is strongly present - a blue sky or a red flower - there will be a spike in that color's histogram. However, the main use of the histogram, as someone said above, is as a warning of over or under exposure when it runs off the ends of the x axis or is bunched to one side.

If color accuracy is very important to you (it isn't to most people, who prefer impressive but not neccessarily accurate color), it is worthwhile learning about RAW and using Canon's DPP program,

It seems like the OP might be a little confused about things.

First of all you must realize that a custom WB is only good for specific lighting situations. If you set a custom WB and then the lighting changes the WB must be set a gain. I rarely use custom WB and generally only do so when I have lighting that will remain unchanged such as a studio setting.

What I do most of the time is shoot in RAW for one, which in case you don't know means you can adjust the WB all you want in post. I'll either try to get the preset in the ballpark if I remember or shoot my WhiBal card, which is basically a grey card that you can use to set the WB in post or I just mess around with the presets in post.

Secondly, like someone already mentioned there is no reason to look at the histogram of a custom WB shot. It's irrelevant. You just take the shot of your grey card, making sure you fill the frame with it and then use it to set the WB.

As for looking at the histogram for exposures, you should not expect that the R, G and B channels will all line up over each other. Every shot will have differing amounts of red, green and blue. if you take a picture of a bright red rose filling the frame and a green background you'll have one green hill on the left side and one red hill on the right. There's no reason the two hills would be exactly overlapping each other and there's no reason that you'd want them to.

gooble wrote in post #4902440
It seems like the OP might be a little confused about things.

Very observant...I was very confused but as you see in my follow ups with little sleep in the last 48 my obesssion here is becoming much more clear.

I bought the gray card less than 24 hrs ago and the sales was showing me stuff with it..I think he was wanting to pimp his Nikon he was selling. But, what he did was continuous explain that I is what " I wanted".

But the fine folks here have got me in line.

As someone else stated, the best way to balance flash and ambient is to gel your flash with an orange gel. This will then give the proper "balance" to the scene. In other words your subject will not be overly blue if you set for tungsten WB or your background will not be overly orange if you set WB for flash.

This is all a tricky part of photography and requires a lot of work to get right. You need to think of flash photography as two exposures in one. The flash exposure on your foreground subject, and your ambient light exposure. They can be different and as you have seen, also have different WB.

One other trick, to not use gels is shoot in RAW. Then in post, "develop" two different shots - one with flash WB and one with tungsten WB. Now you have two photos. Bring them into the same image as two different layers and merge the foreground and background. Voila, you will have one image with the propoer WB throughout!

After re-reading my post, I realized an error. If you gel your flash with an orange gel, you will need to set for the ambient tungsten. This also only works for tungsten light. If you are in a different ambient light (flourescent) you will need a different color gel...

AdamJT wrote in post #4903414
As someone else stated, the best way to balance flash and ambient is to gel your flash with an orange gel. This will then give the proper "balance" to the scene.

Sto-Fen makes the Omnibounce diffuser. I have a white one, but they also make a gold and a green one, for balancing your flash to tungsten or fluorescent ambient light respectively.

If you're bothered by mixed lighting temperatures when shooting flash you can simply eliminate the mix by eliminating the ambient background. You can do this by turning the light off, of course, but you can do it just as effectively by using a higher shutter speed (1/250 is typical) and smaller aperture. The flash will adjust itself to give proper exposure.

-js

Another option, if you are going to take a lot of shots in the same room is to get a daylight bulb. They are tungsten lamps with a blue colour glass and this tends to correct the tungsten orange cast back to somewhere near daylight. They aren't perfect but might be good enough. You can buy them in art and hobby shops and even some photgraphic suppliers as they are also used for viewing prints and paintings indoors.