Manfrotto has been in my professional life since the day I started, more than 25 years ago. I have more stands, tripods and magic arms than necessary, but for some reason each seemed like a good purchase at the time—necessary for some project, no doubt.
It only seemed natural that one of the world’s premiere light stand manufacturers would eventually broaden its scope and introduce a product they had been supporting all these years. Since the roll-out of the Spectra LED light panels, I had been looking forward to test driving these small and portable continuous lights in my commercial work.
The Spectra line includes a total of five LED light panels, with the 900F being the brightest at 900LX measured at 1 metre. The smallest is the 500S, that measures 300LX at one metre. For easy reference, the alpha code in each model signifies the light beam angle, whereby “S” is the designator for Spot Light, and “F” is the designator for Flood Light. The only exception is the FT which identifies the light as having both Flood capability and colour Temperature control, which is variable between 3200 (warm) and 5600 (daylight) Kelvin.
One of the first learned skills for photographers is understanding the interaction between ISO, f/stop and shutter speed, and most understand this early in their careers. However, ask those same photographers to measure light in Lux or Lumens, and they would most likely not know how.
Translating Lux to an f/stop can be a daunting proposition. To assist in the understanding of the light output of the Spectra LED panels, I have measured the 900FT and 900S in a blackened studio with a handheld light meter, and a trusty old carpenters measuring tape. Hardly scientific, but the table below will provide some indication of light fall off measured in f/stop increments.
By knowing the constant ISO and shutter speed, you can now determine what a correct exposure would be for any predetermined light source to subject distance. For example, should you wish to use the 900FT and your daylight ambient exposure in your camera indicates a proper exposure would be f/16 at 1/125 of a second, at ISO 100—this is the sunny sixteen rule in effect—you can calculate that this light panel simply does not have sufficient output to provide any capacity as a fill light. Consequently, at best, it can be used to capture a catch light (light reflection) in the subject’s eyes, if you are photographing a person.
If, however, you are photographing the same person at dusk or night time, and the ambient light measures f/16 at 1 second, at ISO 100, you could effectively use the same 900FT light panel to create at equal illumination of the subject by having the light source 76 centimetres from the subject. Obviously for an over- or under-exposure of the subject, you would simply move the light source to a desired distance.
Working with continuous light sources, as opposed to flash or strobe lights, comes with a small learning curve. As with any piece of equipment, it cannot cover all situations. The task of the photographer is to employ the appropriate equipment for the task at hand.
I could imagine the Spectra series of LED light panels being useful for small tabletop lighting set-ups when shutter speed is not a concern, or creating small levels of fill light when working outdoors on grey-day situations when, again, shutter speeds are relatively long. The Spectra LED panels are not a substitute for flash equipment, but by the same token flash equipment is not a substitute for continuous light sources.
If you are working with non-moving subjects, and you like the WYSIWYG effect (what you see is what you get), the Spectra LED light panels warrant your consideration.