The RadioPopper PX review – part 1


So as anyone who’s been following this blog for any amount of time knows, I’m a pretty big fan of RadioPoppers.  ( I was an early adopter of the P1 system (really the first practical system for wireless TTL with strobes) and I pre-ordered the PXs the moment they came on the market (literally).

So I finally get my grubby little hands on the PXs.  As luck would have it they arrived about 4 hours *after* I wrapped a big shoot, but that’s ok… my P1s still performed admirably…

First impressions – they are small, noticeably smaller than the P1s.  This is a Good Thing™, since the whole point of speedlights is “small and light”  If I wanted to haul around 47 lbs of gear everywhere I would just use monolights and a vagabond, but I digress… No fiber optic = win (the light port is built in) and a removable battery cover for easy access – yay.  Overall if the P1s were more of a “beta” these are definitely the “release product” (see below for PXs vs P1s)



Installing the receivers is fairly straightforward – they come with a nice little diagram to show you where to place the velcro for optimal light-port alignment.  Im not crazy about velcro-ing the front of my flash up, but since the recievers are essentially permanent fixtures I’ll deal.


The good news first – the PXs in basic TTL mode are pretty much plug&play – slap em on, and fire away.  The bad news is that once you get into the menus it gets a little more complicated.  The menu system is a bit arcane, an unavoidable consequence of a 2 character screen and only 2 buttons for adjustment.   Honestly it’s not that bad though.  Once you get the “cycle” of options down, it’s pretty easy to flip through.   The only downside is that with only 2 buttons, going through the menus is pretty much “one way” only – I think that the menu system could be *vastly* improved with the addition of a 3rd button – essentially giving you “up”, “down” and “select” buttons.

My ONLY real complaint with the operation is that I absolutely cannot use the “down” adjustment on the transmitter’s “group” menu (for clarification – the PX transmitter will allow you to remotely adjust the power on a AB/WL monolight connected to the upcoming PX jr.  This is done by going into the “group” menu on the PX transmitter (G1, G2, G3) and selecting a power level from 00 (off) to 32 (full power).  In theory, pressing the “X” button increments the power level, while *holding* X while simultaneously pressing “P” will decrement it.  Unfortunately despite about 10min of fiddling, I could not get the hang of the “holding x+press p”  every time it would either just increment it, or drop it by one and then increment it again.  Maybe I just need some practice 🙂   Again, this would be easily solvable by a 3 button control scheme rather than 2 (you listening Kevin – maybe something for the PX v.2? 🙂

Overall I am satisfied with the operation of the units.  Once you get comfortable with the menu system, making adjustments is not bad, and the real point is that in TTL mode, you shouldn’t really *have* to make adjustments to the units all that often while shooting.

One strange “gotcha” – probably more related to Canon than RP – When using the ST-E2 as a commander, it seems like it must be *on camera* with the camera on in order to operate.  Seems like a kind of “well duh” thing, right?  well, I initially started testing the RPs by sticking the TX on my ST-E2 and pressing the test button to try and fire my strobes (ST-E2 not on camera).  This works fine with the normal optical system, however *did not* work with the PXs – the link light on the TX goes off, but nothing on the RX.   Put the ST-E2 on camera though, and the test button functions normally, TX and RX link and the strobe pops.  Pretty weird huh?  Took me about 15min of frustration to figure that one out…


Of course what it really all boils down to is “do they work?”

As mentioned I received my units right after finishing up a big shoot, so I have not yet had the chance to put them through their paces in a “real” environment, however from my testing performance seems excellent – it just works.  I did my darndest to try and get them to misfire, but was unable to 🙂  I tried using the auto channel select, as well as manually selecting channels and they consistently fired every time.    Tested them out to about 80 feet (stood at one end of my studio with the strobe/receiver by the door all the way at the other end).  No issues.

Not much else to say – we’ll have to see how they perform over time, but so far they have been 100% rock solid.



Bottom line is – if you use wireless TTL flash at all, these things rock.   All the good parts of the P1 and then some.  Better design, operation, and performance along with the inter-operability with manual flash using the JR system.  Super cool.   Even just the ability to use HSS wirelessly is worth the price of admission.   The P1 was a revolutionary concept and a good product.  The PX is a very good product.   The PX+JrX system combination elevates it to a *great* product.

Of course the big elephant in the room is: how are these going to fare against the 800-lb gorilla that is PocketWizard, and their newly announced TTL system.   There is no doubt the new PWs are cool, and basically do everything that the PXs can do *by themselves*.  The key that I think may give RP an edge is the system as a whole.  The integration of all the units, combined with the abilty to remotely adjust monolights and system flashes is *huge* for anyone who uses a combination of speedlights and studio strobes (which I do frequently).  On the other hand, PW has some neat goodies like “hypersync” so there’s that as well… we’ll have to see how it plays out.  For the time being I am more than happy with my PXs, and will be first in line for the JrXs when they hit the shelves as well.


Details are a bit sketchy, but THIS POST on the RP blog, seems to indicate some “hypersync”-like functionality with the JrXs.  My guess is that they are doing something similar – using the signal to “pre-fire” the flash at speeds over the x-sync, so that the strobe is already ramped up to it’s full luminance as the shutter curtain opens, essentially turning it into a very bright continous light for the duration of the exposure.    This has a number of technical ramifications, but another trick in the toolbag is always good.

stay tuned for part 2 – real world shooting and performance tests!

New RadioPoppers coming soon!

Some very exciting news over with the RadioPopper folks…

Looks like the new P8s are coming soon, and will be far more than we expected.  Syl over at Pixsylated has a bit of an insiders scoop on the new units!

No more fiber optic?  Fires TTL and manual(studio strobes)?


I’ve been a big fan of my P1s, but they definitely have their limitations.  They are, well, a first gen product – almost more of a “proof of concept” 🙂  However, judging by the hints going round, these new units are going to be an atom bomb in the world of off-camera lighting.    My speculation (hope) is that they’ve found a way to interface/do ttl communication via RF directly through the shoe (no optical required).  Add a 1/8″ “pocketwizard” style jack for studio strobes and well sign me up because I’ll be ordering one for every light I own.

Even cooler is that they’re offering “trade in” credit for your P1s – As I understand it if you purchased P1s after Oct 12, you will get the full value of your P1 in trade in- having only to pay the price difference for the new unit!   Pre-oct 12, you should still get a credit, but not 100% (thanks for the clarification, Kevin!) Either way it’s a really nice move, especially for us “early adopters” who often get burned when “gen 2” comes out!

December 12 is supposedly the official announcement – let’s see what happens!

The Nuts and Bolts of Off Camera Flash – Part 3, TTL wireless


CLICK HERE FOR PART 2 – Manual Flash

Ok, now that we’ve talked about getting your strobe off camera, and triggering it manually, lets talk about the other “main” option for firing it – wireless TTL

In simplest terms it means that your camera and flash “talk” to each other to automatically determine the proper exposure.  Just like the automatic metering modes for your camera (where it calculates the exposure based on reading the light of the scene) TTL flash does the same thing – lets your camera automatically calculate the amount of flash needed for a scene.  Generally the way this is done is that the camera fires a “pre flash”, a small burst from the flash to “test” the scene, which is read and exposure/amount of flash is calculated.  The shutter is then opened, and the actual exposure is taken with the flash firing to the degree calculated by the pre-flash.

Now bear in mind that although wireless TTL and manual flash both achieve the same end result (firing your flash off camera, they are very different beasts.  Remember all that hardware we talked about for firing your flash manually?  (pocketwizards, cables, ebay triggers etc…?)  None of that will work for TTL.  Remember that all those devices are doing is carying a “FIRE” pulse to the flash.  they are essentially “dumb”.   TTL requires actual communication between the flash and the camera.

The good news is that if you have a modern dslr and “system” strobe (meaning the manufacturere’s dedicated strobe, designed to work with TTL)  you may already be able to do wireless TTL with no additional hardware.

Now as mentioned, modern TTL implementations rely on a preflash to meter the scene, and the the flash fires based on this meting calculation.  When the flash is on-camera this is no problem, since the strobe can “talk” to the camera directly (notice the several other pins on the foot of the “system” flash vs. the manual flash?  those are used for ttl communication)

<- TTL flash foot vs. manual flash foot.

But what happens when we want to take that TTL flash off camera?  Somehow it needs to be able to recieve the metering information to “know” how to set it’s output for the exposure.  Most current camera makers solve this problem by using an optical TTL signal.  In other words, the camera/master uses a series of quick flashes that are “read” by an optical sensor on the strobe, and these tell it the metering/TTL information.  There is a “master” device, usually an onboard flash either built-in or mounted on camera which sends out the preflash communication, and the wireless flashes are the “slaves” that read the flashed signal given by the master and pop accordingly.

This method of communication is actually quite sophisticated.  Most of the current optical TTL systems can control multiple groups of flashes at independent power levels, and power output/ EV compensation can be set directly from the master (it transmits this information to the slaves).  In practice what this means is that you can set flash power level & ratios directly from your camera/master device without having to adjust each strobe manually.  Cool huh?

In terms of a master: Nikon, Olympus, and Pentax all have DSLRS that allow you to use the built-in (pop-up) flash as a master to control slaved TTL strobes, while canon requires you to actually have a strobe mounted on camera (or use the ST-E2, which is a dedicated wireless TTL controller) to control your slaves.   I’m not going to go into the actual setup and configuration of each TTL system, as that is *way* beyond the scope of this article.  Suffice to say, RTFM 🙂  In short, you switch your strobes into slave mode, your camera/master into “master” mode, and then are able to control your slaves from the master, setting ratios and such.  The master tells the slaves how to fire based on the preflash metering information, and Bob’s your uncle…

Now given the advantages of wireless TTL flash, you might be wondering why not always use it and forget about manual?  There are a couple of big downsides to TTL flash:

1 – it is proprietary. The pre-flash ttl protocols that each manufacturer uses to communicate between master and slaves are specific to that manufacture.  What this means is that you are locked in to using that manufacturer’s strobes that support it’s TTL protocols.  Want to use 3rd party? out of luck.  want to mix in studio lights? No dice…  (actually it is possible to do this, but we’re not going to talk about it here 🙂

2 – (and this is the biggee) line of sight (LOS) is required. Since the TTL information is sent optically (by superqick pre-flashes), the camera and strobe have to be able to “see” each other in order to “talk”.   In practice what this means is that you are limited as to where you can place your strobes off camera (since they have to be able to see the signal flashes) and also that these systems become, shall we say, less than reliable in bright ambient conditions or outdoors (since all the ambient light makes it difficult for the sensor to see the signal flashes).   This is a generally “game breaking” limitation for working pros in the field who need to be able to depend on their strobes to fire every time without fail?  (remember I said that rock-solid reliablility is the reason to pay $200 for a pocketwizard over a $20 ebay trigger?  same deal here.)

Enter the RadioPopper…

Much in the same way that a pocket wizard or ebay trigger acts as a “bridge” for the “fire” signal in manual flash setups, the radiopoppers act as a “Bridge” for the visual signal flashes required for TTL communication.

Basically they way radiopoppers work is you have a transmitter and receiver – the transmitter sits on top of your “commander” unit (either an on camera strobe or dedicated commander unit – st-e2 or su800) and “reads” the magnetic pulses created by the master’s signal flashes (apparently the signal flashes generate a magnetic field around the flash head as well).  The transmitter then sends this information via an RF signal, much like a PW (but in this case it is more than just a “fire” signal) to the receiver which has a tiny little LED light inside.  The reciever decodes the RF signal and uses it’s little IR LED to replicate the same signal flashes right in front of the sensor, giving the strobe the exact same optical TTL signal it would have gotten from the commander unit regardless of how far away it is (or around a corner etc…)!  It’s a rather clever setup.  The fact that it is simply tranlating the signals from the master means that it is not system specific – the RadioPoppers will work with both Canon and Nikon’s TTL systems (other systems are not “officially”  supported, but reports have confirmed at least basic functionality with Sony/Minolta and Pentax).

The beauty of Radiopoppers is that since they are essentially just an RF “bridge” for the system’s optical TTL signal, they support all the TTL functionality that the system does, inclusing HSS (High Speed Sync), without the limitations of line-of-sight or range that the optical system imposes.    I personally have a set of radiopoppers, and after using them for a few weeks, I have no idea how I ever managed without them.   Even when I am setting my flash power manually, the ability to do wireless HSS without the limitations of optical TTL is a beautiful thing.  Plus for a lazy slob like me, the ability to control levels/set ratios without walking to each flash is just worth it’s weight in gold.   I really can’t say enough great things about the radiopoppers.

The only downside to the radiopoppers is that they only do TTL.  In other words if you just want to trigger manual flashes or studio lights, the radiopoppers are useless (since they are just an RF bridge for the optical signal) you still need pocketwizards or the like.

Anyway, in conclusion, while off camera TTL is somewhat complex, the hardware needed for it is quite simple – in general it is just a matter of having a compatible master and slave unit – either the onboard flash or hotshoe mounted, along with line of sight to trigger the slave flashes.  If youare limited by the shortcomigns of the optical signaling system, Radiopoppers will give you RF reliablility/capablility while preserving the TTL functionality of the system, so in essence you have a choice between using the built in capabilities of the system or radiopoppers, and that’s about it!  Wireless TTL is a very useful feature (albeit with drawbacks) and in my opinion belongs in the repitoire of every strobist! (If it’s good enough for Joe McNally, it’s good enough for me 🙂

Stay tuned for the 4th and final part, when we talk about the little oddities of flash triggering, notably sync speed and ways to “cheat” it!

Continue to part 4 – syncing and misc. topics!

Radiopoppers working with Pentax! (preliminary testing)

After eagerly following the saga of the Radiopoppers, from their vaporware inception to their current production I finally have a pair in my grubby little hands.  Oh happy day 🙂

(you want a review?  Here’s my review: radiopoppers rock my face 437 ways from sunday.  Get some.)

Now I got them to use with my newly acquired Canon 5D kit, but as it happens I still have some Pentax gear as well.  Officially Radiopoppers do not support Pentax PTTL, but I figured what harm could it do to test.

I mounted the P1 receiver on a Pentax 540FGZ flash.  Flash was set to wireless pttl slave (SL1).  Note that on the 540 the sensor you need to position the bead over is the lower right corner of the face, as you look at the flash *not* the round part in the middle (that’s just the AF assist light)

I set the K10d onboard flash to wireless controller mode, and covered the actual flash itself to ensure no light was coming out and triggering a false positive.   I fired off a few shots, and sure enough no slave firing – good!

Then I turned on the P1 transmitter, and placed it on top of the k10d.  The popup actually seemed to support it’s weight, and the transmitters fit rested nicely against the top of the eyecup.  I think it would be mountable with a little piece of velcro on top of the pop up flash!

The big moment – I fired a shot and sure enough, the slave popped!  Exposure looked correct too (roughly, just by glancing at the LCD.   I ran through a few apertures from 2.8 to 8 and the flash exposure seemed to remain consistent, indicating that metering info is working!  I could visibly see the difference in light output as the flash popped at different apertures as well.
So it seems that at least the basic functionality of the P1s works with Pentax’s PTTL wireless sytem.  it actually fires the flash, and ttl metering appears to work.   Bear in mind however, that this is far from a scientific test and YMMV.  Further testing will be needed 🙂

The Nuts and Bolts of off-camera flash – Part 1, Basics

So unless you’ve been living under a rock (photographically speaking) for the past year or so, you’ve probably heard of David Hobby, AKA The Strobist.  The strobist blog has been singlehandedly responsible for introducing a whole new wave of photographers to the beauty and mystery that is: off camera lighting!

The problem is – a lot of this stuff is still confusing.  Heck, I didn’t “get it” the first time I read through lighting101.  Or the second.  Or probably not even the third.  And a lot of the time, the problem isn’t conceptual, it often comes down to the “nuts-and-bolts” issues – eg, things like “what works with what”, “how do I connect x to y” and “why is there a black bar across my image when I use my flash off camera but not on camera”

What I am going to do in this series of articles, is break down, step-by-step the various hardware and methods needed to get your flash off camera and firing properly.  We’re not going to worry about lighting theory or anything like that – just the “nuts and bolts”.

  • In par 1 (here) we’re going to talk about the basics of how a flash works, and the different modes you can use it in.
  • In part 2 we will discuss options for manual triggering.
  • In part 3 we will discuss wireless ttl flash
  • and finally in part 4 we will deal with some miscellaneous topics, such as x-sync, HSS, rear-curtain sync etc…

So without further ado, lets talk about getting your flash out of the hotshoe and into the wild where it belongs!

Now first of all it is important to understand how a flash actually fires.  In actuality it is quite simple – if you look at the bottom of your flash (or “foot”) there is an electrical contact, the center pin.  If you have a newer “system” flash, it may have other pins as well, but they all have the one center pin.  Now if you look at the inner sides of the foot, they are also metal.   When a connection is made between the center pin and the sides of the foot, the flash fires.

That’s it.  You could make your flash fire by connecting these two contacts with a paperclip even. (although I wouldn’t recommend it and am not responsible if you electrocute yourself trying it!)

So in essence, triggering your flash is simply a matter of making the connection that allows it to release it’s charge as a burst of light.   The catch, of course, is *how we make this connection*.

Now let’s step back for a minute.  Before we think about triggering the flash lets look at the primary “modes” of the flash.   In essence, a flash only has 1 adjustment – power.  In other words, “how much light does it put out when it pops”.  However, there are several ways of *calculating* how much power is needed or desired for a particular situation.

  1. manual.  Back in the day, all flashes were manual, meaning they were essentially “dumb”  *you* set the power output by hand, based on what you calculated was needed.
  2. auto.  auto flash is basically a way that the flash itself measures the amount of light needed based on settings you input.  We will not talk be talking much about auto-flash since I believe manual or ttl are more useful 99% of the time.
  3. TTL.  Stands for “Through The Lens”, and is a method where the camera and flash “talk” to each other and calculate the appropriate amount of flash automatically based on the camera settings and a meter reading.

For purposes of this discussion, we are just going to talk about manual and ttl flash, as I think they are the most useful.    The point to all this is that, despite having the same outcome (firing the flash) the *methods* for triggering your flash are very different depending on whether you will be using manual mode or TTL.

In part 2 we will talk about options for triggering your flash in manual mode, what kind of hardware you need for each, and pros and cons for each option.  Stay tuned!

UPDATE:  part 2 is now up – find it here