Tiffen Lowel Rifa eXchange - Manual (Page 3)

Lowel Rifa ® eXchange ® Instructions
The Rifa eX is a dedicated soft light,
with quick set-up and beautiful output.
With a little practice, good results are
easy to achieve. Rifa eX 55, 66, & 88 all
use the same standard
lamphead & socket.
While you should never use higher wattage
lamps than the maximum recommended for
each model, you can use lower wattage lamps
in the larger models for increased softness at
the same wattage / output.
For example, using the 500 watt EHC lamp in
the Rifa eX 55 at a distance of 5 feet will give
you 72 foot candles of light with the amount of
softness from a 24 square inch source, yet
using the same 500 watt EHC lamp in the Rifa
88 from a distance of 5 feet, will give you the
aprox. the same 72 foot candles of light, yet a
greater amount of softness because its now
coming from a larger 32 square inch source.
The TH-X300 Accessory Lamphead can quick-
ly swap to allow greater use of lower wattage
lamps in larger sized Rifa’s, to reduce output
while retaining softness. It is the supplied
standard lamphead for Rifa eX 44
Postitioning the Rifa
Soft light falls off in output strength much
more quickly than a hard source of identical
wattage, because the soft source is so much
larger in size (light is dispersed in a wider
direction). As a result, soft sources, like Rifa
are designed to be used fairly close to the sub-
ject. This can create problems of light spill on
the areas behind the subject. The first step in
minimizing background spill is to move the
subject away from walls, by 6 feet or so if pos-
sible. This will allow a light placed on a stand
higher than the subject to fall off towards the
floor, before hitting the wall.
First, a brief overview...
Soft light is soft because the size of its source
is large when compared to the size of the sub-
ject being lit. The larger the ratio of light source
size to subject size, the softer the light. If you
stand outside on an overcast day, you will have
very little shadow because the size of the
source (the whole sky) is so much larger than
you are.
Hard light is hard because the size of
its source is small when compared to the sub-
ject being lit. In a fixture such as a Pro-light,
the physical size of the source is much smaller.
This makes the light very directional and as a
result, the shadows it throws are sharper. A
clear sunny day will result in sharper shadows
because of the smaller (harder) source.
Distance from source to
object
becomes a factor in sharpness as
well. The further away from the subject the
source is, the smaller the source appears to be
& therefore the harder its shadows.
Rifa eX Models
There are 4 models of Rifa, with front
diffusers in sizes of
• 16 x 16" (Rifa 44-EX)
• 21 x 21" (Rifa 55-EX)
• 25 x 25" (Rifa 66-EX)
• 32 x 32" (Rifa 88-EX)
So logically, at same distance, the 88 will be
softest of all because its source (the lit diffuser)
is the largest.
Using Fabric Egg Crates
Another situation that can arise as a result of
using soft sources close to the subject is fluc-
tuation in exposure level that can occur if the
subject moves back & forth in relation to the
light source. With the source being so close,
its effect can be noticable in the camera. An
easy solution to this, which can also help
reduce the light spill described previously, is to
add an accessory fabric egg crate to the front
of the light. Soft fabric egg crates are available
in different degrees of dispersion, so where the
Rifa's have an output that will cast light in
almost 180 degrees (with the strongest portion
of the output being in the center 70- 75
degrees), the egg crates will trim this to either
30, 40 or 50 degrees, depending on the model
of egg crate used. They do a great job of pre-
venting the subject from "burning up" if they
happen to get too close to the light source for
your exposure.
Mixing with daylight
For setups when you are shooting in a room
that also has windows, where the desire is to
mix the output of the Rifa with daylight, there
are 2 options.
First, using Accessory eXchange Lampheads,
you have the option of removing the supplied
tungsten-halogen lamphead and swapping to
one of several heads that take screw-threaded
daylight fluorescent lamps. Use only profes-
sional photography lamps, such as our 'On-
Color' 80w, not hardware store specials. They
may be "daylight" but their low Color
Rendering Index will mean poor color rendtiton
across the light spectrum. See eXchange
System Lamphead Instructions Sheet or
lowel.com for more information.
An Introduction to Rifa eX for the New Pro
The second option involves using some level
of daylight color correction gel. The goal is to
match the warmer 3200k tungsten lamp in the
Rifa, with the cooler daylight color (5000-
6500k). Because daylight can vary in color,
depending on whether its direct sun, overcast
clouds, blue sky or any combination of the
above, you will need to choose either 1/4, 1/2
or full day blue to most closely match the Rifa
to the daylight in the room. Rifa Day Blue Gels
are custom cut to fit the Rifa's. They are sized
to cover the front diffuser with enough excess
to allow them to be clipped to the velcro pock-
ets on the side of the light. You can use
clothespins, Lowel Gel-jawz, or any small
spring loaded clip.
These are just some
starting suggestions.
For an in-depth understanding of the creative
decisions involved in the art of lighting, we
suggest a visit to Lowel's EDU section at
lowel.com. You will find an in-depth
lesson on using the eXchange lamp-
heads of Rifa eX. .
3
3:00 9:00
C
B
A Camera
B
3:00 9:00
A Camera
A Rifa eX with 250 - 500W lamp Setup Keys: B Pro-light with 100 - 250W lamp C Tota-light with 300 - 500W lamp
1 Rifa, 1 Pro-light, 1 Tota-light
To light an interview subject with 1 Rifa eX and 1 Pro-light (250w
focusable hard source), try using the Pro-light as a back light to give the
subject separation from the background. Vary the angle to the subject
while keeping the 2 lights facing each other for increased dramatic
results. As you approach a 9:00 / 3:00 placement, the Pro becomes a
hard / dramatic key, as the Rifa becomes soft fill. Note: watch for lens
flare from the back light (Pro). Place the broad throw Tota so it lights
the background without spilling onto the subject. 1 Rifa, 1 Tota-light
To light an interview subject with the Rifa eX alone, You can place the
light at a 45º angle, 2-3 feet higher than the subject, with the light tilted
down towards the subject. From there, you can arc the angle of the
Rifa-lite out in either direction from 6:00 (at camera - this will give the
most even lighting) to either 3:00 or 9:00, depending on how much
dramatic contrast & fall off you want in your shot. Place the broad throw
Tota so it lights the background without spilling onto the subject.
Basic Starter Setups using Rifa eX
www.lowel.com
Setup 2 Setup 1
Soft source close = Softest shadow
Same soft source further back =
Less soft shadow
Direct (small) source = Hardest shadows
Directional Sources have
smaller surfaces