Choice of filter?

[Johnny Eng]

I use daylight balance color positive film (ISO : 50 & 100) all the time. I would like to know which filter I should use to achieve correct light balance when shooting citycape at night. The exposure normally takes 3 - 8 minutes.

[Alan Davenport]

Night lighting in cities is a mixture of discontinuous spectra. There are mercury vapor, argon, tungsten incandescent, various fluorescents, all with different spectra and most of which have sharp peaks at certain wavelengths and nothing at all somewhere else. In short, there is no filter in the universe that will give you correct daylight balance for all of the light sources in a nighttime cityscape. The color casts that result are both unavoidable, and part of the beauty of night photography.

Try shooting it with no filter.

If you find the color balance too warm, an 80A filter will cool down the tungsten lamps, but it may do wierd (and hard to predict) things to metal vapor lamps. You'll need to add 2 stops of exposure for an 80A.

[Kirk Gittings]

I need to hear more. You have two issues. The first is color shift from reciprocity. Then what are most of the light sources? Metal Halide? Sodium?

You could always shoot it with color negative and pick your color balance in a scan.

[John Kasaian]

Just shoot B&W and tell the viewer to use thier imagination ;-)

[Craig Wactor]

I shoot night exposures specifically to get funky colors. I tried some 160T once, and it was so blue it looked like the city was Atlantis! I find that many of the lights used to light the outside of tall buildings are metal halide lights that are extremely close in color temp to daylight. Some of the street lights are, too, but most are high pressure sodium, which turns a very orange amber - warmer than tungsten. Even an 80C won't make it white. Also, there are compact flourescent, old mercury vapor, and low pressure sodium lights. Then you have to deal with the different shades of flourescent light inside the windows, as well as tungsten light sources inside some. The only possible way to make it all look like white light would be to shoot three or four exposures, each one filtered for a different light source, and patch it back together in PS! To me, that would make the shot less interesting than with all the vibrant colors.