Flourescent + Tungsten + Flash - White Balance formula ?

richpips

richpips

Suspended / Banned
Messages
1,687
Name
Rich
Edit My Images
Yes
Whilst I have no problem working out white balance with one type of light. I encoutered issues yesterday with getting the white balance right with multiple illumination sources. (Using the white eye dropper gave a green tinge.)
Q1.

So, is there a way of calculating what the WB is with one or more light sources?

Q2.

Can you get a tungsten emulating filter for a flash, so that the camera thinks that the light source is just tungsten.

Thanks in advance of your numerous helpful replies. :)
 
1. Yes, with a colour temperature meter.
2. Yes, but you need a Colour Temperature Meter to establish what the colour of the tungsten light is, therefore what filtration you need to match the flash to it. You can't assume that any light tungsten source has a colour temperature even remotely near what the manufacturer says it is, mainly because of voltage fluctuations. Come to that, the colour temperature of the flash can be pretty variable too with some makes of studio flash (not usually a big problem with hotshoe flashes though)
 
:shrug:

Picture of a white piece of paper under the same conditions, adjust in PP until W/B is correct and make a note of those settings?

:shrug:
 
Colour correction gels are used to assist with balancing light sources. It's plenty more difficult when facing multiple temperatures though.

Read more here at Strobist

There are colour correction gel sets available from MPEX, also Lee Filters do correction gels too.
 
The only way to do it is to pick the dominant light source and set your camera and flash accordingly. I had this problem at the weekend, the main lighting was flourescent, but there was also a TV crew's lighting and bright daylight coming through the windows. The first pics I took (auto wb and using flash) came out with a green cast on the white walls, indicating that the flourescents were the dominant source, so I reset the camera wb to flourescent and put a green gel over the flash head and the walls were white again :)

As Tomas says, Strobist is the place to learn all about it.
 
Great thanks for the replies.

....off to strobist read more.
 
By all means set your camera for the dominant light source, and by all means believe what you read on Strobist.

Both of these aproaches will make your shots less bad, but neither will make them right.

Of course, 'near enough' may be good enough - it depends on individual needs.
 
Garry Edwards said:
By all means set your camera for the dominant light source, and by all means believe what you read on Strobist.

Both of these aproaches will make your shots less bad, but neither will make them right.
Click to expand...

Hi,
Would you care to elaborate on the above Garry?
 
Tomas Whitehouse said:
Hi,
Would you care to elaborate on the above Garry?
Click to expand...

Simple enough really, if you set the WB for the dominant light source then light produced by that source will be OK, light from other sources won't. How important that is will depend on how much of the subject is lit by 'other' light sources, how bright those sources are and the nature of the shot e.g. it may not matter for a birthday party, it would matter for a pro still life shot.

The same sort of comments really on the Strobist approach. Strobist basically has a lot of excellent advice on making do and mending, using cheap solutions where 'right' solutions may be overkill or may simply take too long or involve too much equipment for the photographer. Their method will get you into the ball park but won't get you anywhere near the goal. Even they say that not all fluorescent light and not all tungsten light is the same colour, that's an understatement...
 
Garry Edwards said:
Simple enough really, if you set the WB for the dominant light source then light produced by that source will be OK, light from other sources won't. How important that is will depend on how much of the subject is lit by 'other' light sources, how bright those sources are and the nature of the shot e.g. it may not matter for a birthday party, it would matter for a pro still life shot.

The same sort of comments really on the Strobist approach. Strobist basically has a lot of excellent advice on making do and mending, using cheap solutions where 'right' solutions may be overkill or may simply take too long or involve too much equipment for the photographer. Their method will get you into the ball park but won't get you anywhere near the goal. Even they say that not all fluorescent light and not all tungsten light is the same colour, that's an understatement...
Click to expand...

Thanks very much for that. The penny drops. :thumbs:
 
Garry Edwards said:
By all means set your camera for the dominant light source, and by all means believe what you read on Strobist.

Both of these aproaches will make your shots less bad, but neither will make them right.

Of course, 'near enough' may be good enough - it depends on individual needs.
Click to expand...

Okay, fair point, for something like a still life shot I assume you would be in a postition to have greater control over the lighting scheme.

Just out of interest (and because I would like to know how to do things properly), what would you have done in the situation I outlined above? To refresh,I couldn't exclude the natural light or turn off either the overhead flourescents or the TV crew lighting. I also couldn't set up anything to block out these light sources.
 
Flash In The Pan said:
Just out of interest (and because I would like to know how to do things properly), what would you have done in the situation I outlined above? To refresh,I couldn't exclude the natural light or turn off either the overhead flourescents or the TV crew lighting. I also couldn't set up anything to block out these light sources.
Click to expand...

Sometimes you just have to accept the situation and just take what comes. And sometimes there are things you can do. And sometimes, although there are things you can do it just doesn't matter enough to spend the time/money getting it right.

I can't tell you what I would or could have done in that situation because I wasn't there and don't know exactly what the problems were.

But one thing you can do (often but not always) given the right equipment, is to overwhelm whatever lighting is causing the problem. A powerful flash, bounced as necessary to make the lighting look natural, can work wonders.

And this is where the Strobist approach falls down, because hotshoe flashes simply don't have anywhere near enough power to do that, or at least not in most situations. My answer is a battery powered generator flash, which isn't as portable as a hotshoe flash but which is a lot more portable than a mains powered studio flash. There are a few on the market, the best ones IMO are the Profoto and the Lencarta. Both output 600 J of power, about x10 the amount of a typical hotshoe flash.
 
Garry Edwards said:
Sometimes you just have to accept the situation and just take what comes. And sometimes there are things you can do. And sometimes, although there are things you can do it just doesn't matter enough to spend the time/money getting it right.

I can't tell you what I would or could have done in that situation because I wasn't there and don't know exactly what the problems were.

But one thing you can do (often but not always) given the right equipment, is to overwhelm whatever lighting is causing the problem. A powerful flash, bounced as necessary to make the lighting look natural, can work wonders.

And this is where the Strobist approach falls down, because hotshoe flashes simply don't have anywhere near enough power to do that, or at least not in most situations.
Click to expand...

That's fine if you have the run of the location but in my example there wasn't the option to use even a battery powered set of lights,it was a speedlight or nothing (as they were filming) which is where the Strobist approach comes into it's own.
 
Flash In The Pan said:
That's fine if you have the run of the location but in my example there wasn't the option to use even a battery powered set of lights,it was a speedlight or nothing (as they were filming) which is where the Strobist approach comes into it's own.
Click to expand...
You were there and I wasn't so I accept what you say - but I can't see much difference between having a hotshoe flash and a small battery generator slung over the shoulder and a handheld flash.

The one I have is about the size of my very first mobile phone:lol:
 
Garry Edwards said:
You were there and I wasn't so I accept what you say - but I can't see much difference between having a hotshoe flash and a small battery generator slung over the shoulder and a handheld flash.

The one I have is about the size of my very first mobile phone:lol:
Click to expand...

If you got your first phone when I got mine (mid/late 80s) then that's bleedin' huge :lol:

I'll have a look at the links you posted as tbh the SB-600 I had with me was really struggling, even with the iso cranked up and the 17-55 wide open :thumbs:
 
Flash In The Pan said:
If you got your first phone when I got mine (mid/late 80s) then that's bleedin' huge :lol:

I'll have a look at the links you posted as tbh the SB-600 I had with me was really struggling, even with the iso cranked up and the 17-55 wide open :thumbs:
Click to expand...

Yes, fond:shake: memories - £200 + £25 a month + 25p a minute, battery life on standby 8 hours in about '87...

The whole point is that with a portable generator flash there's no need to crank up the ISO and throw away quality. I did an outdoor fashion shoot with mine, plenty of power to overwhelm the sun using it at slightly less than full power.
 
OT, but £200, blimey, that was cheap,mine was a lot more than that.

Not as much as my mate's though, he paid £2500 for his Motorola 8000s plus it was £35/month and 50p a minute back then.
 
Flash In The Pan said:
OT, but £200, blimey, that was cheap,mine was a lot more than that.

Not as much as my mate's though, he paid £2500 for his Motorola 8000s plus it was £35/month and 50p a minute back then.
Click to expand...
I don't like spending money, I waited until the prices were almost reasonable and until they almost worked:)

I had a client though, couple of years or so earlier, who wanted one for his car. The works wouldn't fit into his Rolls Royce boot so he bought a Range Rover so he could have a car phone, paying a lot of extra to queue jump the waiting list, the works took up nearly all the luggage space. His wife told me that he only used it to tell her that he was nearly home...

Happy days!
 
I remember going to the car auctions and seeing the dealers with them and thinking mugs theyll never catch on . Whos the mug now I was offered a chance to invest in a shop selling them and turned it down the guy who did it is now worth a fortune
Bob
 
The colour temperature of tungsten bulbs drops by about 1 degree kelvin per hour of use so it is difficult to say with certainty that a gelled flash will be exactly the same colour temperature as a given bulb. Personall, I don't mind the warm look of tungsten when mixed with daylight or unaltered flash, as long as its not overdone. Fluorescent on the other looks like puke.

When I was at college doing TV years back people used to get really hung up on white balance but as long as your close enough and any areas where there are colour casts aren't too unsubtle I wouldn't worry about it.
 
subseasniper said:
When I was at college doing TV years back people used to get really hung up on white balance but as long as your close enough and any areas where there are colour casts aren't too unsubtle I wouldn't worry about it.
Click to expand...

This is fair comment, but it's worth remembering that although the standards of TV shoots are extremely high (I know because I light for commercials) colour errors don't show nearly as much as in a still photo.

BTW, here's an example of a shot where I overwhelmed the sun by using a 600J portable flash
darkbackground_1.jpg
 
I would cheat in this situation, and turn off one of the lights or close the blinds.
 
You could always tell the client the walls were painted light green.........
 
I shoot reasonably regularly for an architect and this is a problem I encounter nearly every shoot. A typical scenario is a room lit by fluorescent with a large window at one end and tungsten wall lights at the other. Three different light sources and temperatures. If I need to use a flash kicker in any dark spots or regions I wish to highlight I then have four light sources with different temperatures.

The biggest problem with this scenario is that the dominant light source in any one area of the room is different. You cannot set a white balance which will give you a pleasing result across the whole room.

I take a master shot white balanced to the overall dominant source. If no light source is obviously dominant I just pick one. I then take the same shot white balanced for each source. All shots are in raw. In PP I tweak the white balance of each image and then mask and layer for each light source. The final image is a composite of the white balanced layers.

Obviously you cannot do this for an event type shoot. In this case I look for the dominant light source on the subject and white balance and gel the flash accordingly. Again, if in any doubt I will shoot in raw and layer if necessary to correct any obviously incorrect WB issues.

The classic or fall back technique I use is to convert to black and white. Works every time :)
 
You must log in or register to reply here.
Back
Top