Forgetting to set your white balance can be huge bummer, especially if you've just captured a once-in-a-lifetime shot.
With the White Balance Lens Cap ($45-65, depending on filter size), you don't have to worry about forgetting to adjust your settings before snapping away.
That's because it's already your lens cap (bonus: it's nothing more you need to remember to carry with you), and all you have to do is go to custom white balance mode, and then the cap creates the ideal profile you need.
No more yellow photos, and no more fixing the photos after they're shot!
I've heard good things about these.
Though honestly, fixing white balance on photos is something I actually enjoy doing. Fiddling with the temperature sliders really lets you see how making something a little cooler or warmer completely changes the mood of a photo.
As long as you shoot in RAW with proper focus, things like exposure and white balance are a lot more salvageable in a program like Lightroom, Aperture, Photoshop, etc.
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