Image before white balance correction
Are you plagued with the problem of strange color casts in your images? Many a times after taking a picture with our little Point & Shoot cameras the results fail to impress us. Having taken a picture, say under a dominating source of fluorescent light or for that matter a tungsten light bulb, the images appear to have a strong color cast. To be a little more precise a tungsten light source will have a yellow color cast and a fluorescent light will have a bluish color cast. Why does this happen? This happens because every light source has a color temperature and that is what is captured by the digital sensor when the image is made.
A Little Background Info on Color Temperature
When discussing about white balance adjustment it becomes imperative to discuss what color temperature is and why the color casts happens in the first place. When heating a piece of metal you may have noticed how the color changes from normal in room temperature to red hot. As you keep heating the metal first becomes blue and then white. These colors, associated with the respective temperatures, is what we are dealing with. Any metal or for that matter any combustible object will impart different color temperature over a period of time as you keep heating it. This is captured by the digital sensor.
E.g., when tungsten bulbs glow the filament inside the bulb (made of tungsten) emits extreme heat and that is what produces the light. This light is yellowish-orange and this is what casts a severe color tone on the pictures shot under that light. The same goes for fluorescent lights and for every other light source.
Unlike the human eye which can adjust itself to any type of lighting condition and clearly identify any color, the digital sensor is incapable of doing the same. It is the process of removing these color casts is what is known as white balance adjustment.
So How Do You Resolve The Problem Of White Balance?
There are several methods to resolve the problem of white balance. You could either
- Use one of the white balance presets that are available on every digital camera, or
- Use a white card to set the white balance right or
- Use the manual white balance settings that allow you to set the color temperature manually in your camera.
The last method is only available in some top-end DSLRs. There is yet another method to adjust white balance and that is to use a photo editing software such as Photoshop or Lightroom. Let’s discuss these methods briefly.
Method 1: Using the White Balance Presets on Your Digital Camera
Every digital camera will have several preset white balance adjustment options. Depending on your camera make and model these will be – (a) cloudy, (b) shade, (c) sunny, (d) tungsten, (e) fluorescent etc. It helps the photographer to set the right white balance adjustment, take a picture and assess the results at the back of the LCD monitor. It is in moments such as these that the true power and convenience of a digital camera is realized. With a film camera there is no way to do this until and unless you have actually unwind the film, process and print them.
The process of using the white balance presets is simple. Usually the option is buried somewhere in the menu. Check the exact menu option for your camera by referring the manual. Usually, however, it is buried under Menu>Shooting Settings> White Balance. Most DSLRs will have a dedicated white balance button marked ‘WB”. Press that and then turn the command dial to adjust the white balance.
If your DSLR comes with two command dials one of them will work for adjusting the white balance. Consult your camera manual or turn both dials one after the other by first pressing the white balance button to figure it out.
Method 2: Using a White Card or Piece of White Paper
The second method involves using a white balance card. Buy a piece of white card that you can use to take a picture; large enough to completely fill the sensor at an arm’s length. This is your reference for the color white in the given lighting condition. If nothing else, a piece of paper will also do, as long as it is white. Before shooting the main pictures simply hold the piece of paper / card in front of the lens, fill the frame and take a picture. Now, set this as the white balance for your camera. What you did was tell the camera what is white in the given lighting condition. Most Point & Shoots will allow you to do this. If you have a DSLR it will also have this option to set custom white balance. This is one of the best methods for adjusting white balance in-camera.
Method 3: Using the Manual White Balance Option
Every high end DSLR will have an option to manually adjust the white balance. This is done by entering a color temperature associated with the lighting condition that you are shooting in. White balance cheat sheets are easily available on the internet. Or you can refer to your camera manual for a start. The idea is to dial-in the right color temperature for your images. If you are shooting in daylight the temperature should be approximately 5500 ° Kelvin. Degrees Kelvin is the unit in which color temperatures are expressed. Again when you are shooting in candlelight the temperature that you should dial-in is something around 1500-2000 ° Kelvin. On the other end of the spectrum if you shooting under a party cloudy day the temperature settings should be around 8000-9000 ° Kelvin.
Method 4: Using an Image Editing Program
Photoshop or Lightroom or for that matter any other editing software will also allow you to adjust the white balance of your images. It is very simple really. It however does help if you could shoot in RAW. When shooting in Raw the images are not processed and the entire unprocessed information hidden in the image file is available for you to manipulate using a Photo editing software.
In Adobe Lightroom 5 the process is rather easy. You need to first import the image to Lightroom. Double-click on the image and then click on ‘Develop’ to enable the editing options. Click ‘Basic’ to reveal the basic white balance adjustment menu. Click on ‘WB’ and choose between ‘Custom’, ‘Auto’ and ‘As Shot’. If you select ‘Custom’ you can slide the ‘Temp’ slider and select the precise adjustment that you need.
Alternatively, you can also adjust the white balance in Adobe Photoshop. Different versions have slightly different paths in order to adjust the white balance. The latest ones allow you to open the image in Camera Raw to adjust the white balance. For more complicated editing where multiple light sources have been used I recommend to outsource to a professional photo editor from a web based service Phowd to give your images the right white balance.
Image after white balance correction by pro retouchers (click to view details)