Jump to content
Sign in to follow this  
Oceanshutter

White Balance with Lights? Wide Angle

Recommended Posts

For those shooting video with a DSLR, I have a question:

 

When shooting wide angle with lights, should I be doing a manual white balance? Or leaving on Auto WB? I have 2 sola 4000's

 

In the past I have always just used available light, and manually white balanced off of a slate or the sand.

 

If I am using a magic filter, I am assuming, that I would not ever want to use lights.

 

Thanks in advance,

 

Dustin

Share this post


Link to post
Share on other sites

Either use a red filter or your lights. When I use my lights I just use auto white balance & when using a red filter I manually white balance every few meters.

Cheers pete.

Share this post


Link to post
Share on other sites

Full disclosure: I am an employee of L&M--not trying to push product below, just to give information:

 

With Sola 4000s, you also have the option of shooting using the accessory cyan filter in front of the lights, in conjunction with your red filter on the camera. This allows you to filter the color of the lights to a color that is close to your background, and use the red filter to get the same white balance for your foreground and background.

Share this post


Link to post
Share on other sites

My approach is a bit different:

 

1) Always use powerful lights... really powerful.

2) Preset the camera's WB to daylight.

3) Never use a Red/Orange filter

 

My logic is:

 

1) Powerful (and this is the important bit) daylight balanced lights will provide a nice natural color fill on the subject.

2) I've got better things to do than mess around with WB. Presetting to daylight maintains consistency...which makes correction during editing much easier if required.

3) I can pick when a filter has been used in video. I personally do not like the resultant color cast, particularly when used in shallow water. Again, why try to correct everything underwater (and thus introduce unwanted color variations) when it's so easy to do during editing (and usually not even necessary).

 

Each to their own...but this approach works very well for me. :)

Share this post


Link to post
Share on other sites

Hey Blaise, can you explain that alittle more please? I don't really understand what you mean. Are you saying that the cyan filter changes the colour temp of the lights?

Also, are they removable underwater?

Cheers Pete.

Share this post


Link to post
Share on other sites

The cyan filter goes on the light.

So, if you have no filters on either camera and light, your photo is blue (cyan).

If you add red filter on the camera, your photo is "white-balanced". (cyan + red = white)

If you add "white" light to this, the photo become "red" (white + red = red)

If you add cyan filter on the strobes, then the light is cyan, and your photos become white (cyan + red = white);

But, the good thing is, in the case you have close + far element on your photo, the close with get the artificial light (cyan + red = white) and the far subjects will get the natural light (cyan+red = white).

so both your close and far subject are white-balanced.

Share this post


Link to post
Share on other sites

Hey Blaise, can you explain that alittle more please? I don't really understand what you mean. Are you saying that the cyan filter changes the colour temp of the lights?

Also, are they removable underwater?

Cheers Pete.

 

Yes, a little more info please. How does this affect white balancing. Should you white balance with the cyan and red filters on?. What circumstances would you use the cyan filters? I have these lights and as I usually (always) shoot macro I'm not sure about wide angle stuff and I'm off to Bali next week for mantas/molas and have no idea what I'll be doing!!

Share this post


Link to post
Share on other sites

Thanks autopsea, i sort of get the idea but i still can't make complete sense of it.

So by adding the cyan to the lights it is changing the colour to the same as that of the camera?

So what happens if i turn the lights on & off? Will that change the white balance?

Do you need to rewhite balance for lights on & off?

Hey liquidguru, i have no idea what i'm doing wether i'm in bali or in sydney.....

Cheers Pete.

Share this post


Link to post
Share on other sites

apparently my post was not so clear : ) sorry !

with an image maybe ?

 

so, for the same in-camera white balance,

 

blue is what you get with no filters.

red is what you get with filter + strobe on close subjects

yellow is what you potentially want, makes you feel there is no water.

 

So here, the Cyan filter is here to compensate the red color that appear on close subject when you have the red filter on.

 

1344420869-filters.jpg

Edited by Autopsea

Share this post


Link to post
Share on other sites

Autopsea's got it. Think of it like this:

 

Normally when you light a subject, the subject is a different color (whiter) than your background, since the ambient light is filtered. Adding cyan filters to the Sola 4Ks (or whatever) filters your white lights so they are a similar color to the ambient light.

 

So, you use a regular color correction filter on your camera, which compensates for both the ambient light and the artificial light. It's a way to increase the light on your foreground while keeping the background the same coloration.

Share this post


Link to post
Share on other sites

How does this affect white balancing. Should you white balance with the cyan and red filters on?. What circumstances would you use the cyan filters?

 

The one rule of thumb for white balancing is: always white balance under the same light conditions you're going to shoot with. So if you're going to be shooting with the cyan and red filters on, then yes, white balance under those same conditions.

 

You'd use the cyan filters if you want to shoot a scene where you're illuminating the foreground, but want the color balance of the illuminated subject to match the background. We're not used to this, because we're used to strobes and video lights changing the color of the foreground subject while we just let the background sort of be whatever color it is.

 

Big-budget shooters have done this for a long time, since they can use gigantic surface-supplied lights. However, for everyone else, we're used to lights that aren't powerful enough to do this. LED lights are just now getting to the point where it's a practical technique for video shooters with portable lights.

Share this post


Link to post
Share on other sites

Big-budget shooters have done this for a long time, since they can use gigantic surface-supplied lights. However, for everyone else, we're used to lights that aren't powerful enough to do this. LED lights are just now getting to the point where it's a practical technique for video shooters with portable lights.

 

 

 

Surface supplied lights were generally very inefficient (20 Lumens per watt) old-tech halogens which are a nightmare to balance with daylight. That's why a lot of the IMAX stuff from not so long ago had very red, unnatural foregound color under daylight conditions.

 

For several years well made and affordable (i.e $1000) underwater HID video lights (50w = 5000 Lumens) have been available which have 5x the efficiency (100 Lumens per watt) and color temp which balances perfectly with daylight.

 

For the last two years well designed LED lights have been available from several (non-USA) manufactuters which put out true 4000 - 5000 Lumens @ 120 degrees (not 70 degrees) at very high efficiency (180 Lumens per watt). Some of these are selling for less than $1500. There are now also several manufacturers offering super-bright 6000 - 9000 Lumen LED lights at reasonable prices.

 

No need for filters...smile.png

Edited by HDVdiver

Share this post


Link to post
Share on other sites

Surface supplied lights were generally very inefficient (20 Lumens per watt) old-tech halogens which are a nightmare to balance with daylight. For several years well made and affordable (i.e $1000) underwater HID video lights (50w = 5000 Lumens) have been available which have 5x the efficiency (100 Lumens per watt) and color temp which balances perfectly with daylight.

 

For the last two years well designed LED lights have been available from several manufactuters which put out true 4000 Lumens @ 120 degrees at very high efficiency (180 Lumens per watt). Some of these are selling for less than $1500.

 

No need for filters...smile.png

 

I know, I work for Light & Motion ;)

 

The cyan filters I'm referring to are more for a specialized shooting technique that balances color across both the lit foreground and the unlit background. They're not necessary for all situations, but for some, it's useful.

 

To get back to the OP's real question though; you should white balance every time your light conditions change. If you're doing a night dive, you could do a single white balance and be good to go for the whole dive since your lights will be the same for the whole dive. In the daylight, if you ascend or descend, turn a different direction from the sun, or go under a coral overhang, you should take a new white balance.

 

Lights and red filters don't mix unless you're using the cyan filters we've been talking about.

Share this post


Link to post
Share on other sites

 

To get back to the OP's real question though; you should white balance every time your light conditions change. ...

... In the daylight, if you ascend or descend, turn a different direction from the sun, or go under a coral overhang, you should take a new white balance.

 

Sorry...I totally disagree. I haven't done a single WB underwater for at least the last 500 dives. :)

Share this post


Link to post
Share on other sites

I think Cyan filters can be (can they?) good as well if you don't use red filters. (talking for photos here).

If I keep a daylight WB on my camera setting, shoot in raw let say a shark face close to me with coral garden behind, strobes ON.

 

With no Cyan filters, if I change the white balance on LR / PSCR on my computer then, the coral garden will be white balanced, but the shark face will become redish (purpleish/orangish actually).

with the cyan filters, because on the non-WB photo the face is even bluer (and that is where I'm not too sure : can it get bluer than blue????) when I change my WB on the computer, both the coral garden AND the shark will be OK.

 

Am I right? or will the Cyan filter not add anymore blue to the original blue?

Is there any way to go further in white balance options than the one proposed in LR/PS ? (further right in the purple and in the yellow for exemple).

 

Thanks !

 

 

Here is an example to illustrate the discussion :

 

White balanced in PSCR, no filters, strobe on :

1344498698-img-5395.jpg

Edited by Autopsea
  • Like 1

Share this post


Link to post
Share on other sites

Sorry...I totally disagree. I haven't done a single WB underwater for at least the last 500 dives. smile.png

 

I'm talking about in terms of generally recognized best practices for someone shooting manually--you must have a camera whose auto-white-balance is pretty good in low-light? I can tell you that with some of the cameras I've shot, the auto-white-balance was so inept that I would get purple water if I didn't white balance manually! I got some ugly footage that way...

 

Working in TV production, the consensus of all the DPs I've ever worked with, both topside and UW, was that you need to white balance when your light changes. These were guys whose motto was "fix-it-in-post is an obscenity!"

Share this post


Link to post
Share on other sites

It was my impression that you wb every ten feet when shooting wide angle..with no lights.

With macro, auto wb with lights. I use a 100mm. That seems to work fine.

 

I guess with wide it is more confusing to me. Because this last trip we would have a very early dive 6:30 am, and I would need to try to use the lights. Becuase the dive was dark. I never got any footage I felt was very good. The lights were on, no red filter, and I white balanced. It was pretty frustrating. So that was 8 wasted dives. The next dive, it was brighter conditions, and I mostly could use the available light without the lights. The next dive was the same, but the forth dive it was getting darker and starting having the same issues.

 

Regarding hdvdiver idea of setting the wb to daylight. I have heard of that before.....but don't you have to do a lot of post work to get it to look good? I would think you do. I don't know a lot about post color correction, so I try to get in camera the best I can.

 

This is an interesting discussion, I don't know that I am ready for the cyan filters, I have known about them. But since they are an extra purchase I have avoided it. Is there any video posted online from a dale using those filters? I would be curious to see how it looks.

 

Dustin

 

 

Share this post


Link to post
Share on other sites

I think the combination of cyan filter for the light and CWB seems like a very logical solution to balance the light-lit foreground and the sun-lit background colors.

 

nex5n-hippo.jpg

 

Stills and videos taken with AWB always turn out unnaturally blue so I prefer taking my time to set and fine tune Custom White Balance to ensure the colors come out as close to what I see as possible. Beside, I won't be able to remember the precise colors hours, days, weeks, or months later. biggrin.png By the way, I cannot adjust the colors in the above AWB image anywhere close to the CWB, using either Photoshop or Final Cut Pro X. Isn't setting CWB in camera = adjusting colors in RAW before most of the color information is thrown away during the JPEG and video-compression process!

 

Large sensors' better high-iso performance can make a huge difference, diving early morning and late afternoon when CWB is pushed to the limits. Just saying... biggrin.png

Edited by A.Y.
  • Like 1

Share this post


Link to post
Share on other sites

Uh oh! Both "To WB or not to WB?" AND the "what color temp for lights?" debates all in one thread? LOL

It's an esthetic choice and there's no hard and fast rule, except the physics involved. Depth, w/wo filter, light to subject to lens distance and type of shot (wide, medium, close up etc) and on the camera end, how to set WB are all variables to consider. Plenty of subjects on those issues and it's a matter of combining them for the look the shooter wants.

To keep this short, if one uses a filter on the lens, then using filters on the lights allow the (lit) foreground subject to be balanced to the ambient light WB, since the lens filter is altering the color temp of light hitting the sensor to see less blue/green. The Cyan filter regulates the reds in the lights to attempt to match the ambient light, so the subject doesn't look red.

That works well with fixed distance subjects because your WB is on the lit subject or foreground and the background. Once the distance of the subject changes (say a shark or turtle siwmming towards the camera) then the color shift will be off color to in color as it approaches the light beam, which isn't very useful for a master shot. That's why filters and lights are used mostly on stationary objects like reefs, where the distance can be controlled.

As for color correction and grading, it's definitely an esthetic choice. Océans messed with gammas and different camera profiles for underwater for many of their ocean shoots, because they wanted to keep the blue in. BBC NHU sorta does the same thing for most of their previous series unless there's like shallow reef stuff or macro subjects which can be lit or WB due to distance to lens.

There are films where certain scenes are lit to have skin color and others don't. Into The Blue was a film where the shallow and closeup scenes had skin color and corrected WB, while the wide shots of the wreck etc did not. I mean, all those hot bods would not have looked good all blue, in a blue bikini no less! :)

With IMAX films, it's a bit more complicated since IMAX was shot entirely on film and thus there is no easy white balance except in post and lighting. For example, Howard Hall chooses to shoot with the Tungsten (Halogen) lights as an esthetic choice. They could've changed the colors in post easily, so it's obviously an esthetic choice, not a technical limitation. The HMI light banks which have been around for years (at least from the late 80s (remember the Abyss?)) were the choice for pool shots. Halogen was more of a 70-mid 80s thing.

 

Also remember that using a filter means the filter will be less bright, because the filters are absorbing light. The bigger the shift the more light absorbed (up to 3 stops). Blaise, how much light is loss with a Cyan filter on a 4k LMI LED?

 

 

@AY

Hmmm is that the Busch Hippo habitat? I ask because from what I know (which isn't much), every wild fresh water area with hippos wouldn't have such a colorful variety of fish species? :)

Anyway, why would you shoot in program and need EC +? is it not easier to just shoot manually and expose using spot metering and histogram, then finishing in post?

And no, RAW does not have WB information set in for still. For video, unless it's RAW codecs like .R3D, ARRIRAW etc, the WB is set off the sensor, even with 3G SDI uncompressed feeds.

Share this post


Link to post
Share on other sites

I guess with wide it is more confusing to me. Because this last trip we would have a very early dive 6:30 am, and I would need to try to use the lights. Becuase the dive was dark. I never got any footage I felt was very good. The lights were on, no red filter, and I white balanced. It was pretty frustrating. So that was 8 wasted dives. The next dive, it was brighter conditions, and I mostly could use the available light without the lights. The next dive was the same, but the forth dive it was getting darker and starting having the same issues.

 

Regarding hdvdiver idea of setting the wb to daylight. I have heard of that before.....but don't you have to do a lot of post work to get it to look good? I would think you do. I don't know a lot about post color correction, so I try to get in camera the best I can.

 

This is an interesting discussion, I don't know that I am ready for the cyan filters, I have known about them. But since they are an extra purchase I have avoided it. Is there any video posted online from a dale using those filters? I would be curious to see how it looks.

 

Dustin

 

I can't believe the ignorance of the comment "fix-it-in-post is an obscenity!" Whoever believes that has a long learning curve ahead of them! What do you think the current excitement of using video RAW codecs is all about. Have you seen what video RAW looks like straight out of the camera?

 

Even with current non-raw codecs there's generally enough color information in the files to do some grading in post. Not just color but gamma etc. Surely the point is to end up with good looking video...My argument is that it's often counter-productive to try and get everything perfect in the heat of the moment underwater...especially when doing long (2 min) takes where the scene changes during shooting. LOL..I really do have better things to do underwater than doing constant WB!

 

That's how we worked in the days of "Daylight" (vs "Tungsten") film...why should video acquisition be any different? Sometimes too many choices (i.e. variable WB settings) on digital cameras can be counterproductive...and bamboozle the user. Then the "smoke-and-mirrors" with filters starts....

 

As I said above...my approach will only work under certain conditions...and the "conditions" relate to hardware/equipment used not ambient light.

 

1) Must use POWERFUL daylight balanced lights with a WIDE beam angle. Get in close to the wide angle subject. Seems that most of the people that can't figure out/disbelieve what I'm talking about are still using relatively low powered lights. If you use low powered lights your dominant lighting is ambient...then have fun constantly doing WB! This is where Keldan Lunas and other genuine 4000+ Lumen lights are absolutely vital equipment as far as I'm concerned.

 

Camera/sensor type may or may not be relevant. The better the low light performance of the camera's sensor and the higher the bit rate, the more information there will be in the final clip. This makes color correction etc much easier in the NLE. However...

 

2) I hardly ever correct WB in EDIUS although it has excellent WB correction...usually just tweek gamma / color cast very slightlly. Brightness levels and color cast (blueness) does vary a lot underwater on the same dive...but I'm arguing that there's a better way to deal with that (i.e. excessive blue) than constantly doing WB. Besides...no amount of WB and funky filters is going to bring back color that isn't there. smile.png

 

On land I DO constantly WB since there it is a meaningful excercise...the full spectrum of colors are present thoughout the day...just the dominant tints are different as the sun goes down. Thus WB does what it's intended to do...balance ALL OF THE AVAILABLE COLORS to give a clean white.

 

UW is different. The colors are REMOVED with depth. So, apart from a clumsy way of minimizing blue cast, how does WB (and or filters) meaningfully restore the full spectrum of colors? It doesn't. That's why I believe powerful lights are important...with the added benefit of reducing the need for constant WB.

 

In SHALLOW water most of the warmer colors are still there. Hence lights are less important...and the scene will repond well to a constant WB setting (i.e. daylight/manually adjusted for early morning or late afternoon). There's also enough color info for the scene to really "pop out" to give beautiful natural colors after a bit of adjustment in the NLE.

 

IF you feel compelled to use filters I would recommend CC30M Wrattens or the nearest non-gelatin equivalent is the cheap and common Daylite-Flouro. Results in a nice correction for both blue and green water AND doesn't make the video look weird like orange filters do in shallow water (or too close to the subject). Even acceptable to use for macro on the same dive (if you can't remove it)...just warms the colors up in a pleasant unobtrusive way. Not my idea...we've been using CCM30's underwater since the 1970's with daylight film.

 

Bottom line...there is no perfect or "correct" approach to this issue. For the first couple years shooting video I was a WB junky. Now that I've found a different (and I think better) approach, I'm just trying to pass on what's a different way of dealing with the not easy task of shooting video UW.

Edited by HDVdiver

Share this post


Link to post
Share on other sites

I can't believe the ignorance of the comment "fix-it-in-post is an obscenity!" Whoever believes that has a long learning curve ahead of them!

 

My previous career was in post-production working on documentaries for NGT and PBS. The cameramen I worked with worked hard with whatever techniques were necessary to get shots as close as possible to corrected color. They had to, since there's only so much color correction that can be applied to compressed camera streams, even when shooting 100mbps DVCProHD, or similar. I learned to shoot from those guys, so my approach is strongly biased towards that. I'm no Howard Hall, but it ain't my first rodeo, either wink.png

 

I do understand that shooting RAW is totally different--and I agree that it will make it much easier to fix colors in post. However, given that most cameras are still shooting compressed codecs without anything near the color latitude of a camera shooting film or RAW video, I believe it's still good procedure to get the colors right (or close to it) in-camera, so that any color correction performed is just a minor adjustment, and doesn't end up pushing the codec farther than its color latitude allows.

 

As a post-production guy who learned to shoot, I know exactly what it takes to correct an image that could have been shot better on location...and I avoid it at all costs in my own footage!

 

You've got a stock footage business, and I don't, so I'm not going to argue with you about what sells, or what makes a successful shooting technique smile.png Clearly, the approach you outlined works great in many situations! I don't think that means it's the ONLY approach that will provide good results, though, and I think that having lots of techniques in the toolbag is the best way to guarantee success.

Edited by blaisedouros

Share this post


Link to post
Share on other sites

I basically agree with you...I was reacting to the word "obscenity". That phrase is incredibly narrow and dogmatic... and contradicts your last comment about "lots of techniques in the toolbag is the best way to guarantee success". If using a good NLE it's possible to do decent color grading even with crappy old HDV material (which I used for several years...so I know it's limitations well).

 

Of course it's better to get the color as close to perfect during the shoot! That's exactly why I always use powerful lights when the ambient underwater light is a monochromatic blue. But no amount of White Balancing by itself is going to give "correct color". smile.png

Edited by HDVdiver

Share this post


Link to post
Share on other sites

You got that right, Blaise! The best solution is the one that works for the chosen shot!

 

Problem is with a DSLR in video mode, it's not as simple as hitting the MWB button and it adjusts automatically. Often it's hidden in a menu, and the CaNikon cameras even require a picture to be taken and used as a reference for MWB. Not something one wants to do constantly esp if the subject isn't constant ie changing depth/distance etc.

 

To answer the OP's question, it's best to MWB on the subject (coral head/reef etc) with lights on subject. Never use AWB because it may shift settings as the scene changes, making it difficult to correct in post.

 

EDIT: There are a lot of buts, ifs and whens to this method. Which is why I advocate learning the physics and applying it vs looking for rules.

Share this post


Link to post
Share on other sites

You got that right, Blaise! The best solution is the one that works for the chosen shot!

 

Problem is with a DSLR in video mode, it's not as simple as hitting the MWB button and it adjusts automatically. Often it's hidden in a menu, and the CaNikon cameras even require a picture to be taken and used as a reference for MWB. Not something one wants to do constantly esp if the subject isn't constant ie changing depth/distance etc.

 

To answer the OP's question, it's best to MWB on the subject (coral head/reef etc) with lights on subject. Never use AWB because it may shift settings as the scene changes, making it difficult to correct in post.

 

So you white balance on the reef instead of a white slate? Wouldn't this give an incorrect "white" to the camera?

Share this post


Link to post
Share on other sites

Sorry I meant for subjects like reef. The most accurate is to have your slate at the same distance as where your subject will be, but most people do 2 ft away and correct in post.

 

EDIT: There are a lot of buts, ifs and whens to this method. Which is why I advocate learning the physics and applying it vs looking for rules.

Share this post


Link to post
Share on other sites
Sign in to follow this  

Sponsors

Advertisements



×
×
  • Create New...