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RadioPopper P1 Radio Wireless System
Range and Reliability
Please see the Release Notes included with this manual or as available on our website at www.radiopopper.com for a
more detailed discussion of all the specifics regarding range and reliability.
It is important to understand the limitations of your P1 system so you may comfortably work within them. You will have
occasional misfires which may be caused by a number of factors. Reading through this section will go a long way to
maximizing reliability and system usefulness in your type of photography.
How ETTL and iTTL Work
Many of the misfire events you may experience are directly attributable to the ETTL and iTTL systems built into the
flashes themselves, rather than the P1 radio system. Please read this section to familiarize yourself with how your flash
system operates.
Your ETTL or iTTL system works by causing the wireless Slave flash to emit two separate bursts of light. The first burst,
called a “pre-flash”, is a dim flash of a known amount of light. Before your camera’s shutter opens, your camera’s meter-
ing system measures this first “pre-flash” and based upon it, calculates the correct amount of light needed to properly
expose your image. Your camera then opens the shutter and commands the wireless Slave flash to emit the second
burst, the “Main Flash” that actually exposes your image.
Pre-Flash with no Main-Flash
One of the most common mis-fire events you are likely to observe is the wireless Slave flash emitting a short “pre-flash”,
but you see no flash contributing to your actual exposure when looking at the picture after the shot in your camera’s
display. It may appear your flash is “firing”, but you don’t see any flash in your exposed image.
NOTE:
If you are using high speed sync, please refer ahead to the High Speed Sync note on Page 26.
This type of mis-fire may be caused by a combination of several factors and will likely occur in a certain percentage of
exposures.
NOTE:
This type of mis-fire will only happen if you are actually using the ETTL or iTTL function of your camera (the
“automatic flash” mode). Some camera bodies, Master Flash devices or IR Controller devices allow you to remotely adjust
the power of your wireless slave flashes manually. In this case they fire at the prescribed power level with each shot
without performing a “pre-flash”. You may find greatest system reliability especially at longer ranges when setting your
flashes to this manual mode. Please refer to your camera and flash owner’s manuals as different hardware may vary
greatly regarding features for remotely setting the power level of slave flashes. If this paragraph confused you, disregard
and just set your flashes so they display “ETTL”, “iTTL”, or something similar in their display.
1. If you’re getting a lot of these misfires (anything much over 10% of your images), you should adjust the Sync Interval
setting on the transmitter (Page 20). A bit of trial and error here should dramatically improve reliability.
2. In much testing of ETTL and iTTL systems
without
the P1 System installed, we’ve found a misfire rate of 5% or more
when the Master flash is fired directly into the Slave flash at a range of a few feet. It is clear that even in the most ideal
