Softbox v. Umbrella
Q. What is the difference in lighting between a softbox and an umbrella,
given the same color, relative size and light source? Or is there a difference?
Good question! Given all other size and color constraints what are the
differences. First the obvious is ease of setup, an umbrella is far easier
to transport, and setup, tend to be on average much cheaper and more flexible
as one umbrella will work with just about any light while most softboxes need
a dedicated speedring for each brand of head.
But no one cares about any of that as its not really important in reality of
use, what is is the difference in control and quality of light from each.
Softboxes:
the primary advantage of a softbox is control, it allows you to control spill
and hotspot. Yes softboxes have hotspots, the better they are designed
the more it is minimized but if the light feathers it means that there is a
hotter pot than not and thats a hotspot. the shape is that of a parabolic,
and while some light passes directly through from the rear mount through the
diffusion panels outward the majority of the light is bounced around in the
box and directed forward based on the exact shape and design of the box to create
a softer wrap and fill quality of light in a directed manor. A silver
lined box is more efficient and more specular creating a less even distribution
of light across the front panel, and white is softer, less efficient and allows
for more even distribution of light across the front diffusion panel.
The deeper the box the more even the light will be coming from the front of
the source. And internal baffle or diffusion panel creates a further softening
by cutting more of the direct light and creating a bounce effect overall prior
to the front panel. Grids can be used to further direct the light in a
specific direction and reduce spill considerably. louvers are also able
to control spill but only in a horizontal or vertical direction. Removing
the inner panel creates a more contrasty light with a stronger hotspot and deeper
falloff. Removing the outer panel while retaining the inner diffusion
panel creates a more umbrella like lighting effect, although it still retains
some more directional qualities it ads some snap and specularity to the light.
Umbrellas come in two main style (material aside) shoot through or bounce.
Umbrellas provide a soft diffuse light with soft shadows and a
smooth highlight to shadow transition. Silver is slightly more abrupt
transitions from highlight to shadow giving the appearance of a snappier light
and produces a more specular light on shiny surfaces, which is a benefit to
jewelry, and fabrics with rich textures although may be a hindrance to skin
texture when the skin has many flaws or is lacking in a good even foundation.
Umbrellas spill all over and are extremely difficult to control and or
flag since barn doors are not easy to work on them, thet may be cut with cutters
placed between the lightsource and the subject but at the point this is an option
most would find it preferred to use a softbox instead. This is very apparent
on dark or low key shots where the soft light is desired but spill is interfering
with a background shadow area. They offer little in control but are great
soft light sources and in general are so inexpensive that they are worth having
in addition to softboxes, and may often be perfect especially in hi key shoots
where the spill works in favor of filling and softening shadows.
Shoot through umbrellas are similar in that they offer little to no control
of the spill, and bounce light all over, but they produce a direct hotspot in
the center which comes from the light being directly aimed out of the front
face of the umbrella. This produces a hotter center with soft falloff.
The second drawback or benefit is that much of the light goes through and a
percentage is bounced back toward the light and behind, in small spaces this
bounced can bounce around off walls and provide a soft fill or may in fact be
a hindrance not only in the waste of light power, but by flaring back toward
the photographer. The hotspot may work in your favor in hi key situations
in that you may aim the hotspot behind the subject where the main subject is
lit by the softer fall off and the hotter light is directed toward the background.
Black backed white convertible umbrellas are a good value for many as they work
as a very soft white bounce with the backing controlling spill or can be used
as a shoot through. I personally almost never use actually shoot through's
but have found that for outdoor shoots, backed shoot through umbrella's, like
the wescott halo or brolly box are more efficient in redirecting and somewhat
softening the hotspot from a direct shoot through but keeping that slight hotter
center and fast falloff. They also prevent the bounce light from bouncing
back toward the photographer and being wasted.
One of my favorite umbrellas is more of a halfbreed, it is
a large soft white convertible bounce umbrella but has a front diffuser so that
the light bounces back through the diffuser and out the front, making it an
even softer and even more uniform smooth light, this is a 60 inch version of
the photek softlighter 2 with removable shaft. This is similar in concept
to the exquisite but awfully expensive design on the Elinchrom 7' octabank.
That design is different from other octobox designs as it has no direct light
as the head is placed facing the rear and the light bounces off the back of
the design and out through two diffusers making the octabank an extremely soft
and even beautiful light source. The softlighter 2 is about $75.00 and
for anyone serious about people photography it should be a must have for that
price. While not the same as the octabank, its design is that of a reflective
diffused light and the removable shaft allows you to set up a full 5 foot diameter
10 panel round light and remove the shaft that protrudes allowing it to be moved
into position extremely close without a shaft in the shot or in the way.
Something worth looking into. It also works as a normal white bounce true
60inch diameter umbrella or normal 60inch shoot through as well, but the real
quality of light is from the diffused nature that creates an amazingly soft
even shadow free light quality for an amazingly low price.
Hope this helps somewhat.
©Stephen Eastwood 2008 www.StephenEastwood.com www.StephenEastwood.com/bio www.StephenEastwood.com/tutorials