I mentioned Dermot's tirade on the evils of post processing last night. Well in an effort to appease him during the Dublin walkabout I started playing with white balance a little. I've shown some of this before back during the Belfast walk around, but I don't think I ever got beyond the 'Look - Post Processing...cool' part.

Now, what I know about white balance would probably fit on a postage stamp, but since I don't have one handy I'll put it all here (and use a font you can read...(bot not comic sans, Geoff gets cross about that)) (look double closing brackets - I used to be able to program computers once!).

Anyway, white balance....

White Balance dates back to the days of film and it's something most of us never encountered as we bought rolls of film from petrol stations, newsagents and the like. The reason being, like ISO, it was the preserve of the 'proper' photographer and people like me who had a point and click camera were given by default (and probably rightly so) a generic white balance mode. 'Proper' photographers would buy rolls for indoor shooting, studio shooting, outdoors etc or use filters and such to change the cast (shade to us Neanderthals) of the light.

It's all to do with physics and different temperatures having different light emission properties...insert physics text here cunningly disguised as a link to wikipedia...

So, as you can see from the wikipedia link a candle would have quite an orange cast (because its not that hot), while a tungsten light will be much more blue (because in light terms its roasting).

... OK, physics (or my attempt at it) over. Basically the film guys had it tough and people like me with digital cameras have it easier. The camera sensor (CCD?) allows the user to decide in advance of each shot what sort of light it is and then make a decision. Fortunately for total amateurs like me, the camera also has an auto setting which looks at the conditions and picks a non-offensive white balance to use.

As Geoff pointed out in the response to some of the Belfast photography stuff the formula the camera uses may be different than another camera or a post processing package. And I guess, that's what Dermot was showing me as well. Sometimes changing it at the point of shooting will give you the best chance of getting the colour and emotion you desire.

Here, take a look at these two pictures of nubile young women* to see what I mean. They're both unedited from the original captures.

First the auto white balance...

Now with the camera set to shade...

(1/4sec, f/8, focal length - 31mm, ISO - 100, 11/12/07 21:45)

In the first picture the camera set the white balance, but in the second I chose shade (which according to my Canon is around a colour temperature of 7000K). Now, the first picture probably gives a much cleaner whiter feel, but the second picture helps (at least to my mind) add a seductive (ooooh look at you) charm and warmth to the images. It depends what you're after I guess.

My point (oh lord there was a point! Physics and a point in the same post, lord help us), is that sometimes its fun to play with camera settings and that things light white balance can be as much fun to play with when taking the photo as in graphics packages later.

If you're into this sort of stuff, it's probably worth reading Geoff's comment as he does give some good insights into it. Hell, I could have just re-posted his stuff here, but I needed to phrase it in my own words to let it sink in.

*Bet that generates a few hits from Google....