Shooting in *.JPG mode is a problem. The data that is dumped leaves the file ‘baked’. Photographers use that term to describe a file where your options for change are limited. It’s a bit like a cake. Once the ingredients are baked, you cannot change the flavor of the cake. You might be able to make cosmetic changes. But you cannot change the fundamentals of the cake. So it is with *.jpg. If your colours or your white balance are off, you cannot change it.
Domestic florescent light bulbs (for example low energy bulbs) are some of the worst culprits for colour cast. They often create a bright yellow colour. The ‘Test Shot’ shown above is an example. Our eyes can normally compensate for the colour cast. The camera cannot. This ambient light shot has picked up a bright yellow cast – actually the background was brilliant white. It was white core board. The *.jpg format means that colour cast is there to stay.
Other colours may appear. Most common are yellows or steely blues. It depends on the bulbs that are present. So if you see these colours appear in your test shots, which is quite common, you need to compensate. If you read your camera manual you can look up White Balance. You will be able to find out how to compensate for these colour casts. In most cases digital cameras have white balance menu-settings for ‘tungsten’ and ‘fluorescent’. So it easy to select the appropriate setting. The next test shot will shot the colour as ‘true’ without the cast.
On the other hand, you can make it easy on yourself. Shoot in RAW instead. This is the type of file where the data in the file is retained. Then you can use an image editor – like PhotoShop or Elements – to change the colours when you are doing your post-processing. RAW files do no have the ‘baked in’ colour problem.
That brings me back to my original point. It is ironic that people think it’s easier to shoot in *.jpg until disaster strikes and everything goes yellow! Actually, since you cannot change anything, *.jpg is pretty hard to deal with at that point.
The motto of this story is… either get your white balance right when using *.jpg, or do the sensible thing and learn to shoot in RAW. The latter is easier and more flexible. And, you can save the day in ways that you cannot with *.jpg.