Paul C. Buff, Inc. Technical Forum

I plan on shooting in a specific location where I'll need to combine Speedlites with Einsteins due to specific space constraints.

Has anyone had any experience with gels on the Speedlites to match the Einsteins, or is this necessary?

Advice much appreciated. Thanks.

I combine the two regularly and have not needed to color balance but then I also usually use the speedlights for rim/hair lights or on parts of the background.

Canon lists the K setting for flash at 6000K. Unless steps are taken to control them, speedlites color temp will rise as power is reduced, same as Einstein in ACTION mode. Unfortunately, I cannot say if 6000K is a mean temperature or the starting temperature at full. Einstein is 5600K at full and stays within 50K in COLOR mode, but does rise in ACTION mode. These specs are from the tube, and modifiers (of any make) and surroundings will likely play a bigger part in unwanted color than the difference in the two flashes.

When I've tested Canon speedlites in the past, there was one color for 1/1 and 1/2 power, then a second slightly cooler color for 1/4 on down to 1/128. They are significantly cooler than sunlight and the Einstein. However, the differences are mainly in color temperature rather than tint. Normally sighted people see tint variations more strongly than color temp.

You can determine this for yourself by shooting a raw image of a WhiBal or equivalent gray card reference illuminated by Einstein in one shot and a Canon speedlite in another shot. Using the white balance tool in your favorite image editor, calibrate each image and you can compare any differences in color temperature and tint.

Color temperature and "tint" are both statements of color shift from ideal. Color temperature is the blue yellow balance and "tint" is the red green axis. Big errors from neutral in either axis are more or less equally visible. Don't ask me why it's structured this way, or why they are specified differently but they been for probably 75 years. All flash units have some amount of R/G axis shift and most have significant amounts of B/Y shift (color temperature).

If it helps, AB and Elinchrom RX series are essentially identical in both axis at a given power setting. Profoto D1 has more shift in both axis, and D! has about 900°K higher native color temperature than the previous Compact series . . . about 6000° vs 5100°.

Most speedlights are close to 6000° at full power and rise as power is reduced.

Einstein is right on 5600° at the flashtube, but the frosted dome drops this to typically 5400°. This is actually good because the 5400° is a near perfect for AB, WL and Elinchrom non-IGBT units set in the middle of their power range.

With any flash you can expect another 200° or so drop in color temperature when bouncing or shooting through unbleached Nylon or Polyester fabrics (good fabrics). Bleached "brightened" white fabric such as Westcott fake PLMs use bleached white fabrics and fluoresce a lot and produce rather blue/magenta casts and well higher than 6000° color temperatures depending on the amount of UV emitted by the particular flash. Einstein, WL and AB tubes are UV coated, and the Einstein frosted dome offers further UV reduction, thus produce quite low levels of unwanted UV emission.

But keep in mind that natural light photography has a very wide range of color temperature and R/G axis difference coming from cloud diffusion (blue) and various color casts caused by the ground environment . . . trees, grass, houses, etc. So 2000° color differences from one side of a subject to the other are not uncommon, and often create interest rather than being considered a defect.