Expert: David Barry - 4/23/2009

Question
QUESTION: Hi, I am a keen amateur & use a D300. I struggle with white balance settings. Most of the time it ends up being a guess. 'AUTO' works OK most of the time, but eventually lets you down in a mixed-light situation. Would you recommend the use of a color temp meter? I've asked a few shops, but no-one that I've spoken to uses one.
Thanks, Phil.

ANSWER: Yes, AUTO white balance in most if not all cameras usually struggles in mixed light, because it's trying to find the best average.

But that problem will not go away with a colour temp meter either. Both film and digital have problems with mixed lighting

No one single white balance setting will cover all types of light at same time, because there is usually just too much difference between them. (Unless you specifically want some off-colour results in your picture)  

You really need to try to minimise the number of different types of lighting, and if you can't avoid it, then either :
(simpler option) if you can, use filters over the lights which are
     different temperature to what white balance you want to use
     or that of the main/brighter light;    or
(much harder option) take separate shots for each of the
     different lights, with appropriate white balance settings
     for each, then merge the shots in software editing if you can.

The main point of using a colour temperature meter is not to allow you to mix the lights, but to get a very precise measurement of what the overall or primary colour temperature is.
So even with a col temp meter (as amazing and accurate as they are with skilled use), if you have mixed lighting, then at best, it can really only tell you what the predominant or overall colour temperature is, or at least the temperature of what you aim the meter at, but won't fix the problem that mixed light sources cause.

As I suggested above, you need to standardise on the lighting (maybe not always possible), NOT try to fix it with white balance settings.



---------- FOLLOW-UP ----------

QUESTION: Hi, thanks David for your help. So would you use a colour temp meter to ensure correct capture or shoot in RAW (then adjust the balance on the computer)?
Thanks for your time.
Phil.

Answer
Yes a colour temperature meter would be worthwhile if you are meticulous and critical about getting the colour right (assuming you don't use mixed lighting), and yes I usually try to get things right in the capture rather than rely too much on computer adjustment.