FX9 white balance - what am I getting wrong?

[seanadl]

Hi all,

I'm trying to figure out where I'm going wrong in white balancing the FX9.

When in the studio I attempted to white balance off of a grey card by zooming into the card in the spot where the presenter's face normally is and clicking on the "wb set" button. This produced a kind of greenish looking color cast over the image. The skintones seemed ok, but the white's were swinging towards the green hue.

When selecting the preset white balance setting and dialing it to 5600 (the temperature of the lights) - the whites looked correct but the face way too red.

Attaching two images showing the results of both. Which one looks correct (if any)? Am I doing something wrong? I have the exposure correctly set. I tried white balancing multiple times using the 'wb set' button and got slightly different temperatures each time (no lighting changes in the studio) - but all of them resulted in the same green cast of the whites.

Apologies if this is a complete newbie question. Also apologies for the facial expressions in the screengrabs - this was during rehearsals.

 

[morgan_moore]

this is clearly a complex scene showint very little grey or white.

im not sure how the fx wb works but I would assume filling the frame with a greycard befroe hitting the button would do wonders.

else..
spin round
stop down
point the camera at the light sources
hit the button

 

[Doug Jensen]

What brand/model of gray card are you using?
Did you try a white card to see if it produces different results?

Your paint menu settings could be throwing things off. Try going to a neutral scene file, such as Standard or S-Cinetone and then re-white and see what you get.

 

[seanadl]

What brand/model of gray card are you using?
Did you try a white card to see if it produces different results?

Your paint menu settings could be throwing things off. Try going to a neutral scene file, such as Standard or S-Cinetone and then re-white and see what you get.

I'm using the gray side of the Calibrite Colour Checker Video card. I'm zooming in as much as possible, focussing on the card and hitting the button. This lens can't zoom all the way. I usually have somebody sit in the host's chair and hold the card where their face is.

I haven't tried a white card - I'll try that next time to see if it changes things. I'll also try a neutral scene file - right now I'm on the Std 5 135+10 matrix.

 

[seanadl]

this is clearly a complex scene showint very little grey or white.

im not sure how the fx wb works but I would assume filling the frame with a greycard befroe hitting the button would do wonders.

else..
spin round
stop down
point the camera at the light sources
hit the button

Not tried white balancing directly off the lights before. I'll give that a go too!

 

[morgan_moore]

Not tried white balancing directly off the lights before. I'll give that a go too!

you want to stop down and defocus.. gonna work best off soft boxes and not really work on point sources?

 

[morgan_moore]

Its a shame you dindt post these frames initially!

m using the gray side of the Calibrite Colour Checker Video card. I'm zooming in as much as possible, focussing on the card and hitting the button

 

[Doug Jensen]

I'm zooming in as much as possible, focussing on the card and hitting the button. This lens can't zoom all the way. I usually have somebody sit in the host's chair and hold the card where their face is.

How much is "as much as possible"? You need to fill at least 80% of the screen with the card, but as a rule, I never WB with less than 100% coverage. If you can't zoom in far enough then move the camera in closer, white balance, then move it back. That is a pretty routine thing to do for most of my interview setups these days with prime lenses and short zooms.

 

[Doug Jensen]

you want to stop down and defocus.. gonna work best off soft boxes and not really work on point sources?

White balancing on a single light source may not give a true representation of the color if there are different brands of lights in the room that don't have matching color temps and matching color accuracy. Plus there might be ambient light in the room, bounced light from walls and ceiling, etc. It is much better to hold a white card where the talent's face will be after all the lighting is set -- as the OP has said he is already doing.

BTW, the talent needs a backlight to provide three dimensional separation from the background, which his hair and jacket are just melting into.

 

[Peter C.]

Like Doug pointed out you need a hair light that’s more noticeable to me than the color.

If your using a green screen it’s a common problem if the subject is too close green reflects on to them.

The other cause of green tint is fluorescent lighting (pointed out by Chris below) whether that from light panels or general room lighting that hasn’t been shut off.

Related to this if you’re filming in a location with mixed color light sources it can be difficult. If you want the face white balanced the it’s best to have the subject to hold WB card directly in front of their face not on the table.

I wouldn't spend too much time on any one aspect of production.

 

[cyvideo]

Hi all,

I'm trying to figure out where I'm going wrong in white balancing the FX9.

When in the studio I attempted to white balance off of a grey card by zooming into the card in the spot where the presenter's face normally is and clicking on the "wb set" button. This produced a kind of greenish looking color cast over the image. The skintones seemed ok, but the white's were swinging towards the green hue.

When selecting the preset white balance setting and dialing it to 5600 (the temperature of the lights) - the whites looked correct but the face way too red.

Attaching two images showing the results of both. Which one looks correct (if any)? Am I doing something wrong? I have the exposure correctly set. I tried white balancing multiple times using the 'wb set' button and got slightly different temperatures each time (no lighting changes in the studio) - but all of them resulted in the same green cast of the whites.

Apologies if this is a complete newbie question. Also apologies for the facial expressions in the screengrabs - this was during rehearsals.

Where do I start? This answer is long as it needs to cover a process to deliver "White". For the casual observer don't bother to read. For anyone stuck with similar situations the following may help you out.

If you stick almost any camera on a white card and pull a balance the chances of pulling a 100% spot-on balance is like 1/100. Also "Preset" white settings are only an approximation for any given location. They are "preset" under ideal reference lighting setups. Which is something you are very rarely ever going to work under

Question? Are the lights in that studio "true" video lights? a greenish cast can indicate a nasty fluorescent bias. Very common with cheaper fluoro and LED sources that have a nasty green spike and can be low in blue value. If the lighting is broken spectrum lighting such as cheap Fluorescent and LEDs these lights can spike green quite badly anywhere between 500 and 600 nm wavelengths. This, not saying it is but this may be the cause of your green cast.

If you are in charge of the lighting and can control things it's much simpler because you can introduce lighting covering the full spectrum and delivering a high CRI value. Trying to get a camera to 'auto' pull a white balance under colour-biased conditions is generally not super successful. Sometimes on OBs in various city locations, we have to shoot with mainly the venue lighting. In those cases, we have to introduce the correct offsets in the camera's white circuitry if we have color biases or casts. Right, how do you correct this in-camera? Do not despair, modern cameras come with nearly all the tools built-in to correct these sorts of issues.

The manual pages listed below are from the FX9 manual I have here. If they are not the same in your manual you'll have to dig through it to find the appropriate pages. First, find page #103 and look for "Video Signal Monitor Off / Waveform / Vector / Histogram." By default, it is normally set to OFF. Set it to "VECTOR".

Now got to page #86 and look for "Shooting >Offset White - Sets white balance offset settings"
Many shooters use this menu for warming up or colling down a shot. It works great for that but it's not what it was designed for. Most broadcast cameras have all these menu settings for a reason. Not wanting to sound patronizing but they are there for a very good reason. It's very helpful to learn how to use these tools to your benefit. On OBs we use CCUs and have CCU operators set up (paint) the cameras till they all look basically the same even though they may be in various locations where the lighting can also vary from camera position to camera position.

Right, to proceed, we should now have a Vectorscope, small though it is in the viewfinder. While observing your Vectorscope pull a white balance at about 65-70 IRE with as much of the screen filled with white as possible. Preferably full-screen white. Now observe your Vectorscope. If you have been 100% successful you will have a white DOT right bang in the middle of the Vector. The chances are in biased lighting conditions you won't have a white 'dot' in the middle of your Vectorscope. It may be close but not in the middle.

Now, this is where you go into your page #86 menu "Shooting >Offset White". In that menu, you have two offsets available. One for memory A and the other for memory B. Turn ON Offset White <A>. Let's just assume we are working with memory 'A' for this example. Under the 'A' menu there are two sub-menu items. Offset Color Temp<A> and Offset Tint<A>. Now while observing your white DOT, which is somewhere in the center of your Vectorscope start adjusting the menu items Offset Color Temp<A> and Offset Tint<A>. Adjust one at a time. Go mad just run the numbers up and down on the Offset Color Temp until you see which way the white dot is moving. Once you know how the +/- numeric adjustments affect the white dot aim to move the white dot into the center box of the Vectorscope. Do likewise with the Offset Tint. It will be a push-pull exercise on those two settings to dial the white dot into the center of your Vectorscope center box. Once you have the dot in the center box your white balance sheet should now look "White". You now have a true white balance. If you now want to warm up the shot or cool down the shot use the Offset Color Temp<A> to achieve that warm/cool shift. If you are going to have to use this location and lighting on subsequent days I would suggest you save a new "Scene File" specific to that studio lighting setup for future recall.

I trust this may be of some help.

Chris Young

EDIT:!!!
Remember to turn OFF your Offset White to go back to normal white balances as those offsets will be retained and applied to your next white balance if you leave the Offset White turned ON.

 

[morgan_moore]

White balancing on a single light source may not give a true representation of the color if there are different brands of lights in the room that don't have matching color temps and matching color accuracy. Plus there might be ambient light in the room, bounced light from walls and ceiling, etc. It is much better to hold a white card where the talent's face will be after all the lighting is set -- as the OP has said he is already doing.

BTW, the talent needs a backlight to provide three dimensional separation from the background, which his hair and jacket are just melting into.

Of course.. Im suggesting how to get out of jail when presented with a chap with a pink shirt on a blue background (and no card)

then the OP reveleals that he has a card that he may or may not be able to fill the screen with.

This changes things.

And you take it to a full tutorial on mixed brand of lights..

This also changes things.

Id then change it further to suggest there is artistic choice.. for example having a golden hairlight that you want not to correct but leave golden.

How is that going to pollute the white card.. maybe turn it off when metering?

Honestly ive only moved from 5500k a couple ot times ever. in very big yellow spaces. Personally i think it simplest to swing a couple of k in post.. but then Im not live and do post.

 

[Doug Jensen]

.. for example having a golden hairlight that you want not to correct but leave golden. How is that going to pollute the white card.. maybe turn it off when metering?

If the backlight is properly positioned the light from it will not strike the front of the white card during white balancing, so it doesn't matter if it is on or not.

 

[LennyLevy]

First - what whites? I don't see any in this picture at least.
1 - Cy's suggestions will work as a way to ajust your settings so they look better no matter what your initial white balance looks like.
2 - As Doug suggested I would start by comparing your setting with a neutral setting like S-Cinetone . It could be your matrix. just because someone told you to use their settings in them matrix doesn't mean you'll like them. I never heard of that setting that 135 +10 before. Screwing around with matrix numbers is a very complicated business and I've never seen anyone use numbers like those. I don't want to knock it - It might be great but don't take it as gospel. can send you my own if you're interested. Most people think it looks great and very neutral. Actually "F55 like" is generally a nice preset in the camera also, but with any matrix setting you still have to experiment with black levels saturation and even phase to make sure it suits your individual shot and gamma.
BTW - Std 5 is a really old fashioned video look.
3- It could be your lights. If the lights are magenta then the preset shot would look like this one does. However the white balance should correct for it without going green .
4- How reliable is your monitor in the field when evaluating .

 

[norway]

Of course.. Im suggesting how to get out of jail when presented with a chap with a pink shirt on a blue background (and no card)

then the OP reveleals that he has a card that he may or may not be able to fill the screen with.

This changes things.

And you take it to a full tutorial on mixed brand of lights..

This also changes things.

Id then change it further to suggest there is artistic choice.. for example having a golden hairlight that you want not to correct but leave golden.

How is that going to pollute the white card.. maybe turn it off when metering?

Honestly ive only moved from 5500k a couple ot times ever. in very big yellow spaces. Personally i think it simplest to swing a couple of k in post.. but then Im not live and do post.

The white balance is obviously being disrupted remotely with microchips by a cabal of sinister people at the World Economic Forum. :2vrolijk_08: