Three Light Sources, One Room
Here is a situation that arrives at almost every wedding and that almost nobody plans for. A room has old warm lamps in the ceiling, a run of LED string lights along one wall, and a wide door standing open to the afternoon. Your eyes see one room, evenly lit and rather lovely. A camera sees three different colours of light overlapping, and it has to pick one of them to call white.
Why colour casts happen at all
All light has a colour, even light that looks perfectly white. Household filament lamps are strongly orange. Older fluorescent tubes lean green. Daylight is blue by comparison, and shade under a clear sky is bluer still. LEDs are anywhere at all, depending on what was bought, and cheap ones often have odd gaps in their colour that make certain fabrics behave unpredictably.
Your brain corrects for this without asking you. Walk from a sunlit garden into a room lit by warm lamps and everything looks briefly orange, then within a minute or so it just looks normal. That correction is so effective that most people go through life unaware that the light around them changes colour constantly.
A camera does the same thing, but it can only do it once for the whole frame. It picks one colour and calls it neutral, and everything else in the picture shifts relative to that decision. In a room with one kind of light, this works perfectly. In a room with three, it cannot.
What that looks like in a photograph
The symptom is faces that do not match. Set the correction so that the couple under the warm lamps have natural skin, and the guests near the open door go cold and blue. Set it so the door looks right, and everyone inside turns orange. Add a green-leaning tube overhead and one side of a face can pick up a tint that looks like illness rather than a lighting quirk.
It is worse on skin than on anything else, because we are extraordinarily good at spotting when a face is the wrong colour and completely relaxed about a wall being the wrong colour. It is also worse in group photographs, where several people are standing in several different lights at once and there is no single correction that serves them all.
And it is largely not fixable afterwards. Editing can shift the colour of a whole image, and it can do a fair amount to a selected area, but it cannot cleanly separate two colours of light falling on the same cheek.
The fix is nearly always to remove a source
Because the problem is having three colours rather than having the wrong colour, the reliable solution is subtraction. One kind of light, whatever kind it is, always photographs better than a mixture.
- Close the door, or open it fully. Half-open is the worst case: enough daylight to fight the lamps, not enough to win.
- Switch off one bank of lights. If a room has warm downlights and cool spots, turning off whichever set is doing less work is usually an improvement.
- Draw a curtain on one side. This is the standard move in a getting-ready room where daylight from one window is competing with bathroom lights.
- Move people rather than lights. Two paces towards the window puts everybody in daylight and settles the question.
None of this needs equipment and all of it can be done in under a minute, which is why a photographer will often walk into a room and start quietly turning things off before lifting a camera.
Where mixed light causes the most trouble
Three places, reliably.
The getting-ready room. A window on one side, a mirror with its own lights on the other, and often a bathroom door standing open with something entirely different behind it. Getting hair and makeup done facing the window solves it, and has the useful side effect of being the best light in the room.
The reception at the transition hour. Late afternoon, when the venue has switched its lamps on but daylight is still coming through the windows, is the single worst moment of the day for colour. It sorts itself out as the sun goes, so a speeches slot placed slightly later can be markedly easier than one placed slightly earlier.
The dance floor with coloured lighting. Disco lighting adds saturated colours that are not really light in the usual sense at all, and they land on faces in patches. Warm white uplighting produces far kinder photographs than saturated blue or magenta, and a request to the DJ or lighting supplier to keep the strongly coloured washes off the faces and pointed at the walls and ceiling costs nothing.
What to ask, and when
- Ask the venue what the evening lighting actually is, and whether banks of it can be controlled separately. Being able to turn off half the room is worth more than any decor upgrade.
- Ask your decor or lighting supplier to favour warm white over saturated colour for anything that will land on people. Colour on walls is lovely. Colour on faces is a problem.
- Ask whether string lights and the house lights are the same colour. They usually are not, and it is easy to check on a venue visit by photographing a white napkin under each.
- Ask what the lighting looks like when the power is out. Emergency and backup lighting is often a completely different colour from the normal fittings, and if load shedding lands in the middle of your reception, that is the light you will have.
When mixing is actually the point
It is worth saying that mixed light is not always the enemy. Warm lamps inside a venue set against the deep blue of the sky just after sunset is one of the most attractive colour combinations available at a wedding, and it works precisely because the two colours are separated: warm on the people, cool in the background, no overlap on anybody's face.
That is the underlying rule, in fact. Mixed light is a problem when two colours fall on the same person. When they occupy different parts of the frame, it stops being a fault and becomes a reason to make the picture.
So the practical takeaway is simple enough. In any room where photographs matter, aim for one kind of light on the people, and let the other colours live in the background where they belong. Close a door, kill a bank of lamps, move two paces, and skin will look like skin.
