AE lock and white balance question.

[mike62]

I am loving my 450D and the 55-250 lens you pros recommended is great even in my novice hands.

I have read about AE lock and white balance and viewed some nice videos from Lark on YouTube but needed some clarification.

Is my AE lock best used when I don't want to underexpose? I understand if I am photographing bldgs. in a bright sky I might want to AE lock on a darker bldg. so the bright sky does not underexpose my bldgs. right? If I had an outdoor shot with subject under trees with a bright sky would the AE lock benefit me here? Would you AE lock on a bright area in order to counter the surroundings?

White balance......from what I learned it was suggested to focus on a white sheet of paper, take your shot, then set your WB to that shot to give you the best lighting shot.

I guess I am just asking for clarification as to which is best used in what circumstances.

Thank you.

[JTL]

I understand if I am photographing bldgs. in a bright sky I might want to AE lock on a darker bldg. so the bright sky does not underexpose my bldgs. right? If I had an outdoor shot with subject under trees with a bright sky would the AE lock benefit me here? Would you AE lock on a bright area in order to counter the surroundings?Yes. But, be aware of the limited dynamic range of most dslrs. In your building example, you may get properly exposed buildings, but most likely, the sky would get blown out. If your subject is more than a full stop different than the surroundings, sometimes the only solution is to take bracketed exposures and combine them in post-processing to get greater dynamic range. If its a scene that has a fairly well defined line between the dark and light areas, you could use a graduated neutral density filter in combination with your AE lock to even out the exposure.

As far as your white balance question goes...for setting a custom white balance, follow the instructions starting on page 90 of your user guide. From a practical standpoint, the only time you ever really need to set a custom white balance is if you were shooting indoors without the flash since artificial light will shift the colors and auto white balance doesn't do such a great job with artificial light. The white balance presets are a little better than using auto WB, but custom WB will give you the most accurate color in that situation.