Did you ever wonder how some cityscape photography gets that deep blue hue in the sky? The secret is to shoot at “magic hour.” Shooting at magic hour can lend a deep, chroma-rich palette to your images. However . . .

“magic hour” only lasts 20 minutes:

The so-called, “magic hour,” is a short window of time long-favored by cinematographers (and, still photographers) for capturing deep-hued, darkened-blue skies, captured only during the precious few minutes approximately 20-30 minutes preceding a sunrise, or 20-30 minutes after the sun has set. Unfortunately, the best part of magic hour really only lasts about 10 minutes.

Location: Los Angeles; time of year: Spring, 7 April 2011.

06:49 PM PDT–28 minutes prior to sunset (camera is facing north):

07:17 PM PDT–sunset (camera is facing south):

07:45 PM PDT–magic hour “begins:”

07:55 PM PDT–magic hour “ends:”

Note that frames #1 and #2 (above) are daylight-balanced. Frames #3 and #4 are tungsten-balanced in order to shift the sky’s color-rendering even blue-er.

using tungsten-correction gel on your flash:

You can create the same dramatic effect when shooting people during magic hour. Below are examples shot just a few minutes apart, and show the difference between a standard, in-camera, daylight-balance, and an in-camera, tungsten-balance, while using a color-corrected gel on the flash to match the color temperature of the in-camera setting:

a.) daylight-balanced; no correction gel on flash:

b.) tungsten-balanced; CTO correction gel on flash:

c.) daylight-balanced; no correction gel on flash:

d.) tungsten-balanced; CTO correction gel on flash:

In the shot above, my flash (a Nikon SB-800 Speedlight with a 3′ octa coming from the right) was covered with CTO (color-temperature orange) gel to correct the daylight flash to a tungsten color temperature. CTO is actually warmer than tungsten, so I typically dial-in a manual color temperature in my camera to about 2,500° Kelvin. Since my camera was balanced to tungsten, the ambient daylight shifted to a deep blue hue making for a more dramatic effect.