I see the new iPhone 3G display has a warmer and more reasonable color temperature of ~6900 Kelvin (K) instead of the original iPhone’s ~8300K. Thank goodness. The original device was way too cool, and much cooler than any natural or common artificial lighting. Daylight averages 5000K and interior lighting averages somewhere around 3500K. I wish all digital devices were in the 4000-5000K range. If they were, the viewing experience across devices would be easier on the eye and color matching would be improved.
I think the reports of the firmware update changing the color temp are misinformed as it is unlikely that such an update would make that change. The new color temp is surely due to the new backlite light source hardware which, in an industry-wide trend, are moving to warmer color temps to get closer to natural daylight. The super cool, blueish LCDs that have been so prevalent over the past 5 years will hopefully become a thing of the past. Warmer displays are critical for print-to-screen matching and more accurate color viewing
Here’s a quick test: compare the whites on your iPhone (or any other phone) and compare that to a white piece of paper. It’s important that they be reasonably close for fairly accurate color viewing and print to screen matching. The iPhone 3G does this better than the devices before it and when combined with Safari’s color managed browser, (more…)
Contrary to popular myth, white balance should bet set using a white card instead of a gray card. It is, after all, a *white* balance that is being set, not exposure for middle gray. Software developers including Thomas Knoll have confirmed this with me. While the distinction between using a gray or white card may not be huge, I have found it to be somewhat significant in some situations. While using a gray card is better than nothing, I encourage photographers to replace their grey cards with white reference cards like the ColorChecker White Balance, ColorChecker Gray Scale, orginal ColorChecker, QPCard or WhiBal. Non-reference quality white objects, such as a white piece of paper should be avoided because optical brighteners can negatively effect the white balance process.
One hidden benefit to using a white card is that you can also use it to find the optimal exposure. While there are details and exceptions worth discussing, I’ll simplify here by encouraging users to use the lightest exposure that doesn’t blow out the white card as indicated either by a camera’s RGB histogram or it’s flashing, blown out highlight indicator.
Determining optimal exposure and white balance in-camera is a common training topic for my business, espicially for high volume JPEG shooters that seek optimal print results with zero color correction. Naturally, the same concepts apply for RAW format shooting as well. So switching to a white card and not only helps improve white balance accuracy but also helps photographers fine tune their exposures so as to minimize post processing.