Amateur Photographer - UK (2019-07-27)

subscribe 0330 333 1113 I http://www.amateurphotographer.co.uk I 27 July 2019 19

AWB

3,000-7,000K

Tungsten

degrees Kelvin

White

fluorescent

Daylight

Flash

Cloudy

Shady

Candle

Sunrise/

sunset

Tungsten

Photoflood

The higher the

wattage of lightbulb,

the higher the colour

temperature

Flash

Overcast sky

Hazy sky

Clear blue sky

Presets

3,200-7,000K

1,

2,

3,

4,

5,

6,

7,

8,

9,

10,

Average

midday

sunlight

Electromagnetic spectrum

30mm 1mm 10nm 0.01nm

Visible light

700nm 600nm 500nm 400nm

Radiation

type

Wavelength

(approximate)

Radio waves Microwaves Infrared Ultraviolet X-rays Gammarays

COLOUR temperature is measured in kelvin – a measurement of

temperature most commonly used in science which starts at absolute

zero, with no minus fi gures like Celsius or Fahrenheit have. At one

end of the scale, we have orange light at 1000K, going all the way

up to blue light at 10,000K, as the diagram above illustrates.

We often refer to colour temperature and light sources from a

subjective point of view: red, orange and yellow light are referred to

as hot, while blue or green light are considered cold, but the reality

in terms of kelvin is actually the opposite.

LIGHT is a form of electromagnetic energy, and the visible spectrum

is made up of violet, blue, green, yellow and red. These colours

combine to make white light, which is typically what you’d get

outdoors around midday and from fl ash.

The colour temperature of light obviously falls within this spectrum,

and understanding how white light is made up of these constituent

colours can be useful when working with different light sources,

coloured gels, and when shooting at sunrise and sunset.

Colour temperature

and the Kelvin scale

The visible light spectrum

Raw vs JPEG
When shooting in raw it really
doesn’t matter what the white
balance is set to because you
can easily correct it during
post-processing without any
detrimental eff ect on image
quality. However, it’s still
best to have white balance
set correctly while shooting
because it makes reviewing
images on the LCD screen
more eff ective since colours
look correct.
When shooting JPEGs, on

the other hand, it’s much more

imperative to set the correct

white balance – and especially

if you tend not to edit

your images. However, the

availability of the Camera Raw

fi lter in Photoshop does mean

that you can change white

balance as easily as you would

with a raw fi le, but it remains

better to set the correct

white balance at the point of

capture because you’re not

manipulating the pixels

that make up the image.

This was taken

in the middle of the

day in white light

Sony A7R III, 16-35mm,

0.8sec at f/13, ISO 100

ILLUSTRATIONS BY MAGGIE NELSON