White balance options for video lights (Wide Angle)

Im looking for advice of recommended white balance strategies for filming using video lights.

Im primarily a photographer so have a good grasp of the theory there but obviously video is different (less light, no RAW etc).

I currently have a V6K (12000 lumen) single video light and primarily testing wide angle subjects, diving in the tropics.

What is the best option for getting a sensible white balance with this type of setup?

I did experiment setting the colour temperature of my lights as a white balance but havent found the results there great - far too green and washed out. Is this simply because the light isnt powerful enough ?

Im getting far better results on auto and the deeper i go, the better it is (i guess due to less ambient light getting in the way,again, is this just a lack of power)?

Is there any merit in trying to take a manual white balance via a grey card or slate with the light on and using that? Last time i tried that i had some very odd colour shift and results so maybe its my technique?

Im aware for wide angle i really need 2 lights for coverage and 12,000 isn't overly powerful which wont help but basically im looking for advice on the right technique to get a decent white balance on the video.

In short: do a custom white balance at the depth you're going to film with the light on at full power off a grey card the same distance away from your lens/light as the subject you're going to film.

That should produce the most accurate white balance on the subject itself, but there's some caveats:

* You are dealing with a mixed color temperature situation -- the temperature of the light falling on your subject is not going to be the same as the light falling on other parts of the scene, so you have to choose which parts of the image you want to have 'accurate' color. Often this will mean your subject ends up looking right, but the white balance required is such that the rest of the scene is still blue/green or, worse, the water column becomes a desaturated gray mush or even purple.

* Your camera may not be able to set a white balance sufficiently warm enough to account for the filtration of reds/oranges/yellows by the water column. Most cameras can only push white balance to 10000k for JPEGs/Video, where the actual white balance you need is closer to 20, 30, or 50000k. So even using the method described above, you may still end up with bluish-green images.

* You can't expect your light to be effective beyond about 1 meter (same as strobes really)

* You really need more light power to get vibrant warm colors on your foreground subject for wide angle in tropical conditions. But you'll get the best results from what you have by filming when the ambient light is not so strong -- that means, early in the morning/late in the afternoon, on overcast days, in murkier water, and deeper.

Think of it this way -- the light that falls on the subject is a combination of the ambient light and the artificial light you introduce. Both these sources start out as full spectrum white light, but they're filtered to varying degrees by the water they have to pass through. So the sunlight might have to travel through 20 meters of water from the surface to the subject and to your camera whereas the artificial light might have to travel through 2 meters of water from your light to the subject and back to the camera. The ambient light is obviously going to be cooler in temperature as a result, but the actual white balance you need will depend on the exact relative strength of your light and the ambient light. That's why you need to set a custom white balance as described above. And that's why you want to shoot in weak ambient light conditions, to maximize the effect of the warm light from your torch.

I am reading here with interest (mainly UW photographer, but interested also in video)...

I could not find out which region of the frame my cameras (Oly EM1II & EM5II) take for coustom WB - entire frame or just the center part (an EMail to Olympus about this remained unanswered so far).

=> In case it would be the entire frame, what I assume, I see problems with coustom WB using a white/grey card (or white fins, what I heared several people are using): Would be impossible to cover the entire frame at the right distance (as far as I understand the problem, the distance between lights/camera and object is crucial for appropriate WB).

=> Currently I am trying to find someone who saws me a white/grey "Bathing Hood"-like structure that I could put over the domeport to make coustom WB. That should serve the same purpose as the expensive special WB domes from Nauticam ( https://www.nauticam.com/products/8-5-white-balance-acrylic-dome-port;https://www.nauticam.com/products/9-white-balance-glass-dome-port )...

Interested to hear feedback, or even better, where can one just order a semitransparent white Bathing Hood that would serve this purpose?

Wolfgang

The mixed white balance situation is unavoidable really when shooting video or stills because the range of your light/strobes is really quite limited so reef structures and fish beyond that gradually become bluer/greener, so generally you want the right white balance on your main subject which means the correct white balance is more or less the colour temperature of your lights. The light will cool off a little as the light need to travel from the light to the subject and back to you. So long as your lights are powerful enough setting WB to your the colour temperature of your lights may be a good starting point, You might want to set a few points higher depending on how much red the water pulls out on the lights journey out and back again. On stills generally you want to shoot with strobes at 4600K +/- as that results in deeper blues in the background water when the subject is white balanced properly. So this means the colour of your artificial light sets the blues colour in the water column when the subject is properly colour balanced.

In theory AWB should be OK and that's what I use with strobes on stills, but on video the WB might shift as more or less water comes into the frame so having a fixed WB is probably an advantage. The weird effects in the water column will vary with how any particular camera does its white balance and this may influence how you choose to set your colour balance.

BTW when talking colour temperatures, traditionally higher colour temperatures are regarded as cooler in photography so 10000K light is cooler than 5000K light even though in physics a black body emitting light has to be much higher physical temperature to produce 10000K light compared to 5000K light. Though to make your image warmer you need to push your white balance on the camera towards cooler light.

I am reading here with interest (mainly UW photographer, but interested also in video)...

 

I could not find out which region of the frame my cameras (Oly EM1II & EM5II) take for coustom WB - entire frame or just the center part (an EMail to Olympus about this remained unanswered so far).

 

=> In case it would be the entire frame, what I assume, I see problems with coustom WB using a white/grey card (or white fins, what I heared several people are using): Would be impossible to cover the entire frame at the right distance (as far as I understand the problem, the distance between lights/camera and object is crucial for appropriate WB).

 

=> Currently I am trying to find someone who saws me a white/grey "Bathing Hood"-like structure that I could put over the domeport to make coustom WB. That should serve the same purpose as the expensive special WB domes from Nauticam ( https://www.nauticam.com/products/8-5-white-balance-acrylic-dome-port;https://www.nauticam.com/products/9-white-balance-glass-dome-port )...

 

Interested to hear feedback, or even better, where can one just order a semitransparent white Bathing Hood that would serve this purpose?

 

 

Wolfgang

Not sure how Olympus does it, but with Panasonic, it shows you a square area in the center of the frame which is what (I assume) it uses to set the white balance. Really, you don't have to be 100% precise, if you get the white balance in the right ballpark, you can make minor adjustments in post even when dealing with jpegs/compressed 8-bit video files.

I have no experience trying to white balance through something translucent, but this is inherently not the most accurate way to white balance because it doesn't account for the extra distance the light must travel from the subject to your camera lens. The difference may not be worth stressing about, especially once you're pretty deep.

The mixed white balance situation is unavoidable really when shooting video or stills because the range of your light/strobes is really quite limited so reef structures and fish beyond that gradually become bluer/greener, so generally you want the right white balance on your main subject which means the correct white balance is more or less the colour temperature of your lights. The light will cool off a little as the light need to travel from the light to the subject and back to you. So long as your lights are powerful enough setting WB to your the colour temperature of your lights may be a good starting point, You might want to set a few points higher depending on how much red the water pulls out on the lights journey out and back again. On stills generally you want to shoot with strobes at 4600K +/- as that results in deeper blues in the background water when the subject is white balanced properly. So this means the colour of your artificial light sets the blues colour in the water column when the subject is properly colour balanced.

 

In theory AWB should be OK and that's what I use with strobes on stills, but on video the WB might shift as more or less water comes into the frame so having a fixed WB is probably an advantage. The weird effects in the water column will vary with how any particular camera does its white balance and this may influence how you choose to set your colour balance.

 

BTW when talking colour temperatures, traditionally higher colour temperatures are regarded as cooler in photography so 10000K light is cooler than 5000K light even though in physics a black body emitting light has to be much higher physical temperature to produce 10000K light compared to 5000K light. Though to make your image warmer you need to push your white balance on the camera towards cooler light.

There is one way you can try to avoid the mixed white balance situation -- using blue filters of varying strengths on your lights or strobes to try to get their light output to match the color temperature of the ambient light (and setting a MWB for the ambient light). Here's an example of such filters: http://keldanlights.com/english/products/filters/ambient-light-filters/index.html

This can create more blended/natural transition between your light foreground and unlit background. The downside is that you lose one stop or more in terms of the power of your lights, so you'd better have very strong lights to begin with (or shoot when the ambient light is really low).

I Set my wb manually in camera to match my lights for about 15m and below. Shallower than that on a sunny day I’ll just turn my lights off and custom white balance off something grey ish, if I have nothing around I’ll just use my palm.

I do like the idea of the blue filters for your lights but let’s be honest, we all feel like we could use more light than we already have.. having something that cuts that power down seems very off putting imo.

There is a significant difference between the way we light video and stills.

With stills, when shooting wide angle, we light the foreground subject with a strobe and then balance this with a "correctly exposed" background. Hence we would tend to expose for the color temperature of the strobe's output.

With video, the light is used to lift shadows and, if used correctly, is not really visible in the footage. Hence, WB should be based on that of the ambient light, not the light's.

As mentioned above, Keldan actually offer color correction filters for their lights that correct their output to match the ambient's color temperature.

Adam

There is a significant difference between the way we light video and stills.

 

With stills, when shooting wide angle, we light the foreground subject with a strobe and then balance this with a "correctly exposed" background. Hence we would tend to expose for the color temperature of the strobe's output.

 

With video, the light is used to lift shadows and, if used correctly, is not really visible in the footage. Hence, WB should be based on that of the ambient light, not the light's.

 

As mentioned above, Keldan actually offer color correction filters for their lights that correct their output to match the ambient's color temperature.

 

Adam

And white balancing off something that your lights are illuminating is only gonna create the same image as setting your wb manually to that of your lights would (or close enough anyway so that it could easily be correct in post)

Im probably missing something tho, do correct me!

There is a significant difference between the way we light video and stills.

 

With stills, when shooting wide angle, we light the foreground subject with a strobe and then balance this with a "correctly exposed" background. Hence we would tend to expose for the color temperature of the strobe's output.

 

With video, the light is used to lift shadows and, if used correctly, is not really visible in the footage. Hence, WB should be based on that of the ambient light, not the light's.

 

As mentioned above, Keldan actually offer color correction filters for their lights that correct their output to match the ambient's color temperature.

 

Adam

With video lights becoming more powerful now, it's actually possible to approach video the same way you would approach stills -- expose for the ambient light/background, and then light the foreground subject to restore color. In this sort of scenario, your white balance will be close to the color temperature of your lights (if your lights are sufficiently strong enough to outcompete the sun). Or perhaps a little bit warmer to compensate for the cooling influence of the ambient light and the filtration of the water column between your lights, your subject and the camera.

Here is a screen-grab from a video illustrating the results:

I tend to prefer the greater color contrast you achieve this way between warm foregrounds and cool backgrounds to the blander results you get by white balancing to the ambient light. That might be because I started doing wide angle photography with strobes and transitioned to video later

I think the situation is a bit different here from the theory

In stills you use strobe and then use auto white balance the background colour lacking is not usually an issue as all you care about is the blue and how the blue looks like

In video likewise if you have a light strong enough to lit your foreground you use auto white balance there too and as you shoot 1/50/60/100/125 you have way to change how the blue looks

The issue has been historically that video lights were narrow and weak. Now video lights match strobes in terms of field of view but do not yet match strobes in terms of power things are becoming possible and in close up definitely there is no problem

The issue arises when you have a wide angle scene that has a mix of foreground and background where the lights do not cover here the Keldan trick is an option to use custom white balance with lights on instead of just ambient light

I have also seen people shooting filter (red) and light so things are possible with streches,..

The situation is the exact same for big scene wide angle stills using strobes. Yes, strobes are more powerful than video lights still, but they're not effective beyond 1 meter or so either, so you're still dealing with a mixed white balance situation. I believe people do use blue filters on the strobes sometimes too, in conjunction with manually white balancing for the ambient light when shooting big scene wide angle.

I have never heard of blue filters for strobes the contrary you tend to use warming filters

I think the difference between stills and video if you look at the keldan example is that with strobes you typically light up the foreground and don't really care about the colour of the background other than getting a nice blue

In the keldan example you have sharks going around and you want to illuminate the one coming close making sure that thoes behind look a similar color so put the blue filter on the light white balance so the light only helps exposing the foreground details instead of also bringing the color in

This of course will work well only at shallow depth where white balance is effective so the light looses the purpose of bringing back colour in favour of an homegenous scene

I have never heard of blue filters for strobes the contrary you tend to use warming filters

Blue filters are used for fluorescence excitation.

Take the exact same shark-close with far sharks in the background situation that you're describing, except now you're shooting stills instead of video. Wouldn't you want the background sharks to be the same color as the foreground one? Whether you're shooting stills or video, the same two possible schools of thought about white balance apply, and the same techniques are used to produce the desired result:

(a) Create a scene with both foreground and background illuminated by light of the same color temperature for a 'natural' look. Technique: set white balance based on ambient light, use strobes or video lights with blue filters to match the ambient light temperature to fill in the shadows on foreground subjects; or

(b) Create a scene where white balance differences between the foreground and background illumination create stronger color contrast and more subject 'pop'. Technique: set white balance based on the color of your strobes/video lights; get nicely warm-colored foreground subjects set against a rich blue water column for maximum color contrast between subject and background. Optionally, you can use warming filters on your strobes or video lights to create even more color contrast between foreground and background and achieve richer blues in the background by setting you white balance cooler (e.g. around 4000-4500k).

There's nothing that says you must use technique A for video and technique B for stills. You can use either technique for video or stills depending on the artistic vision you have.

For stills it does not really matter because you have a single frame in that single frame what is behind does not matter

In the same situation and 30 seconds video you shoot the shark from the distance coming to you here you want to make sure it does not change colour

On a single close up is totally the same as dreifish says

Keldan color correction (light) filters: http://keldanlights.com/english/products/filters/ambient-light-filters/start-ambient-filters.html

They are blue and are not excitation filters!

I think I perhaps misspoke in my reply above. I would use auto WB when using lights (assuming the camera will WB). With a camera that will not WB well underwater, I guess I will force it to WB, but would normally try and use a slate and WB off that.

With stills we can control the color of the background by using shutter speed. This is not really an option with video.

Practically, I find that video footage in which I can see the effect of the light looks unnatural. I prefer the lighting's effect to be more subtle.

Keldan color correction (light) filters: http://keldanlights.com/english/products/filters/ambient-light-filters/start-ambient-filters.html

 

They are blue and are not excitation filters!

 

I think I perhaps misspoke in my reply above. I would use auto WB when using lights (assuming the camera will WB). With a camera that will not WB well underwater, I guess I will force it to WB, but would normally try and use a slate and WB off that.

 

With stills we can control the color of the background by using shutter speed. This is not really an option with video.

 

Practically, I find that video footage in which I can see the effect of the light looks unnatural. I prefer the lighting's effect to be more subtle.

Curious to find out why u would auto wb instead of setting it manually to avoid shift in colors. Any perks that I might have missed by using auto wb or just personal preference?

Leaving the WB on auto would automatically compensate for changes in distance between your camera and the subject for example -- so the further away the subject, the more water your lights have to travel through, and thus the more of the warm colors that get filtered out. Whether this actually produces better results than fixing your white balance to the color temperature of your lights (or slightly warmer to account for the slight attenuation from the water) probably varies from camera to camera. It's certainly worth trying out, but may indeed lead to weird color shifts during your shot.

Auto WB also could save you the trouble of changing your white balance between dives if conditions change (e.g. water clarity changes).

I guess it depends what camera you’re using. Auto wb on the gh4 was not worthy haha. Haven’t tried it on the gh5 yet but assume it won’t be great. Might just be me tho.

I guess it depends what camera you’re using. Auto wb on the gh4 was not worthy haha. Haven’t tried it on the gh5 yet but assume it won’t be great. Might just be me tho.

Auto white balance and filter works wonders on Sony cameras...and it is the only option as it fails to do custom. Once you correct tint to your liking is great

On Panasonic I have not tried auto white balance yet which I would only do with filters as I have not yet identified the right filter but this is coming soon when I will try magic and some other gels

Panasonic tends to be weak on yellow and turn orange green so need a way to kill that part of the spectrum together with the blue

I have used custom white balance and I have to say am not totally impressed by results off camera however once corrected in FCPX results are very good provided you have latitude to correct

What Keldan scenario support is a custom white balance with light filters and lights. The alternative would be a red filter without light that of course would miss some details

Now my point is if I am shooting video at 1/50 which is the speed I operate and I keep aperture around f/5.6 and with wet lenses you can get to f/3.5 loosing one stop to the filter is not a great deal in clear water. So the 45' example with keldan light in clear water shallow bottom for me is not particularly interesting and that is a scene I would keep doing without lights

Dreifish example under the rock instead is a clear light scenario where you need wide beams