F/1.0

CLICK HERE FOR PART 1- Basics

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!

REPOST FROM 6/28/07:

Independence Day is coming up, and that means fireworks shows! Now admit it - we’ve all been guilty (at one point or another) of whipping out a little pocket camera and snapping away at the fireworks, handheld, in P mode, probably with the dinky little on-camera flash going too. Yeah, I’ve done it too…

BUT…

with a little effort and a bit of technical know-how you can go from blurry, underexposed, globs-of-color-on-film shots to beautiful, crisp, rainbow bursts that will be the envy of your friends and neighbors! (grin)

(note: a lot of the techniques here are similar to the ones in my article on photographing lightning, so you may want to read that as well (LINK -opens in new window))

First things first:

GEAR:
most of this will be assuming you are using an slr/dslr. You can shoot fireworks with a pocket digicam, but it is harder. If you have one with manual controls, most of this info will apply, but pocket cams have never been known for good long/low light exposures so YMMV.

you will need:
1. a camera (duh). at least something that lets you control the aperture and has a “bulb” mode (meaning the shutter stays open as long as the button is held).
2. a tripod. we’re talking exposures of several seconds, it is impossible to hold the camera steady. Tripod is a must (the sturdier the better to cut down on “mirror slap”)
3. a cable release. used for bulb mode. Note that most wireless remotes will *not* do “bulb”, only set exposures. There may be some out there that do, but most likely you will need a *corded* remote release.

Now, on to the specifics:

TECHNIQUE:
first, set up your gear. make sure the tripod will not be disturbed/bumped during the exposures. Set up the camera on the tripod, attach the cable release. Frame the anticipated “action” area.
Before the show starts, put your camera in Aperture priority mode and take a few “test” shots to determine a good exposure, (I prefer slightly on the dark side). I like to adjust it to an aperture that will give me a decently exposed image at a shutter speed of about 2-4 seconds (since this is usually about how long I open the shutter with the release.) this isn’t an exact science, it’s just to get a rough estimate the the aperture needed for your approximate exposure time. Since the actual bursts of light will expose regardless, we are basically just calibrating the exposure for the ambient light here. Once you are comfortable with the exposure, leave the aperture set as it, and switch into M (fully manual) mode. Turn the shutter speed all the way down until it goes into “bulb” mode. Now you can manually control your shutter - when you press the button down on the cable release, the shutter will open, and stay open until you let go of the button. This way you can exactly control when the exposure stops and starts.
note: make sure you camera is set to manual focus, else you will lose shots while it “hunts” for a focus lock. Most likely focus will be set to infinity, but if you are really close/have a long lens you might need to adjust. Regardless, get it set and leave it.

There is a “rhythm” to photographing fireworks, once you get the feel for it, it’s pretty easy to “anticipate” the exposures. You can usually hear the rocket going up, a second or two before it bursts. This is when I like to start the exposure. Hear the rocket - CLICK - burst - wait a second or two for the “trails” of the burst to expose - release shutter. That’s basically it! I find most of my exposures are in the 3-5 second range. As the show goes on you will probably adjust your aperture, or even set a “preset” exposure as you find the “pattern” of the show. Either way, you still generally want to be starting your exposure right as the rocket goes up before it bursts. The exception to this is when the show gets really “intense” and many rockets are going at once, it can be difficult to tell by sound alone. In these cases, hopefully you have a general idea of the exposure needed, and I will sometimes just set an “average” exposure and just keep clicking the shutter. Kind of “spray and pray”, if you will

TIPS AND TRICKS:

What lens to use?
- this really depends on 2 things: how far away from the action you are, and how tightly you want to frame the shot. Farther away = longer lens, closer = wider. The examples on this page were shot with an 85mm lens (equal to 127.5mm when using a 1.5x crop camera, like most dslrs) I was about 4 blocks away, shooting from a balcony of a high rise apartment building. I like a pretty tight framing, as it allows the actual fireworks to dominate the picture, rather than extraneous elements, so I tend toward longer rather than wider.

Framing the shot / vantage point
- This is a matter of personal taste, but I like to include the surrounding scenery in my shots to give “context” to the fireworks. (As opposed to pointing the camera up an having just the bursts against an empty sky). Usually the best way to do this is to get to a high point, so you have an unobstructed view of the surrounding area. I happen to be lucky in that my apartment’s balcony looks out over the Philadelphia Art Museum (where the fireworks show occurs), So I’ve got a great vantage point without leaving the home. But even if you don’t you can probably find something. If you live in an urban area, many high-rises have roof decks that make great spots. Tops of parking garages are also good. If you’re in a rural area, this might not be as much of an issue, since there is probably more space, and less “stuff” to get in the way of the shot, but a high vantage point is still good.

- The clearest shots often come at the beginning of the show, and after pauses in the shooting (of fireworks that is, not photos!) this is because the accumulated smoke will either not be too bad yet, or have had some time to dissipate (respectively).

-Speaking of smoke; if possible, is is advantageous to set up in an orientation where the wind is blowing at a 90 degree angle to your position. This way, the accumulated smoke from the rockets will blow out of the picture frame as quickly as possible, leaving less to “muddy” your shots.

Capturing multiple bursts.
- A cool trick if you are using bulb mode is to capture multiple bursts in one exposure. Basically they way you do this is to use bulb mode to keep the camera’s shutter open, expose one burst, then cover the lens with something to block out extraneous light, but *keep the shutter open* until the next burst, uncover the lens to expose the burst, re-cover it and so forth…

The trick here is to have something that will block light out of the lens, but NOT TOUCH IT, as the vibrations of bumping/touching the lens will ruin the shot. One common method is to use a black/dark colored baseball cap - the “bowl” of the cap will block light from entering the lens without touching it (this is what I do). You could also use a black piece of cloth, a black cardboard cylinder with one end capped etc…

Basically the sequence goes like this:
- As the first burst starts, expose normally using bulb, however, when the burst ends, instead of releasing the shutter, leave it open and with your other hand, cover the lens with your cap/coth/whatever, being careful not to bump/touch it.

-Wait

-As the next burst starts, remove the covering for the lens, expose the burst.

Repeat as desired (note,you may have to close down the aperture for these kinds of shots to compensate for the increase in ambient light over the length of the exposure)

Finally when you have enough bursts, release the shutter to finish the exposure.

CONCLUSION:
I hope these tips help you all get the most out of your holiday fireworks pictures. Photographing fireworks is not all that difficult once you get the hang of it, and can yield some spectacular results.

Enjoy the holiday everyone!

So I’ve done the cardboard snoot thing.  It’s cheap.  It works.  but I find they don’t last too long trashing around in a camera bag.   I really like the idea of a flexible snoot like the Honl speedsnoot, so I figured I’d try to make my own…

A quick trip down to Perl (art supply store) yielded the required materials.  2 9″x12″ sheets of “foamies” craft foam (it’s a thin, neoprene like foam material - flexible yet rigid enough to hold it’s shape) one white, one black and 4′ of velcro “wrap” (the velcro that has hooks on one side and loops on the other, so it can stick to itself if you wrap it around something)  The neat thing about the foamies sheets is that you can get them either plain or with one side covered in adhesive.   I opted for a plain black and an adhesive-backed white sheet.

total cost for materials: about $5 (the velcro was $3 and I think the foamies sheets were .59 each)

Once at home, I simply peeled the backing off the white adhesive side, and laid the black sheet on top.  Pressing firmly secured the 2 together.  They can bend and flex together without wrinkling or buckling.

I then cut 2 velcro wraps long enough to wrap around the flash head and secure it tightly.

TaDa!  instant snoot - total time to construct: about 15-30 seconds

the best part about this snoot is that it is adjustable.  For a normal throw, wrap it into a cylinder shape, and secure each end with a wrap.   If you want a tighter throw, wrap it into a cone shape.  You can get a very tight dot of light this way.

Another added benifit is that it can be used as a bounce card - simple wrap one end around the flash head pointing up, and leave the other end free.  presto bounce card.

For five dollars and a minute of work, this is something that will have a permanent place in my camera bag!

note: this is the 2nd part in a 4 part series of articles - if you missed part 1, find it here

As we mentioned in part 1, manual flash is essentially a “dumb” flash mode- meaning that no flash metering is done by camera or strobe.  you simply adjust the power to whatever you want, and when the flash pops, it fires at that power, every time regardless.

now aside from the control and creative aspects of using manual flash, (for more on that check the strobist blog) one of the great things about it is that it gives you the greatest range of hardware to work with.  In essence, any strobe that has a manual setting will work with any camera capable of triggering a flash!  NOTE - one *large* caveat to this is that some older strobes use a high trigger voltage, which can fry the delicate electronics in newer digital cameras.  Just be careful if using old/used flashes and double check to make sure the voltage is safe for your camera.  This isn’t an issue with any current/modern strobes AFAIK.

Of course the downside to having such a wide variety of hardware to work with is that there is no real establish “standard” for hooking it all together!

So let’s take a step back for a moment.  Consider if you had a manual flash in your hotshoe, on camera.  How does it fire?  Well, as we discussed in part 1, to make it fire you just have to “close the circuit” in the “foot” to allow the capacitor to discharge, making the flash go pop.  So what happens when you push the shutter is that the camera sends a little pulse to the center pin in the hotshoe, which creates that circuit and allows the flash to fire.  Shutter clicks, flash goes pop, and voila - you got a flash exposure.   So now in order to do the same thing with the flash *off* camera we need some way of getting that same “FIRE” pulse from the camera to to the strobe when you click the shutter release.  That’s really it - all the various cables, pocketwizards, wireless trigger etc… are in essence doing the same, simple thing - providing a way of transferring the FIRE pulse from the camera to the strobe.

So - there are basically 2 ways of getting that trigger pulse from your camera to your off-camera strobe.   You can use a wire that physically carries the signal directly from camera to flash (as if it were sitting in your hotshoe)  or you can use some flavor of wireless transmitter, which “carries” the signal wirelessly.  As the simplest (and likely cheapest) option, let’s talk about wires (or sync cables) first.   Pretty straightforward - it’s just a piece of wire!  One end connects to your camera, one end to the flash.  You click the shutter, the signal goes down the wire, and the flash pops.  Of course it’s the whole “connecting to camera and flash” that becomes confusing, since there are several different physical connectors that can be used!

Although the good news is that since there is no “communication” through the cable (remember all it is doing is physically transferring the “FIRE” pulse from the camera) the connectors are practically, if not physically, interchangeable.  Meaning if you have connector X on camera and Y on flash, you simply need a cable with X on one end and Y on the other (or an adapter that converts X to Y)

The second piece of good news is that for all practical purposes, there are only 4 types of connectors you have to worry about.  They are the “PC” connector, the “Household” or “HH” connector, the 1/4″ monoplug and the 1/8″ miniplug (shown below)

The PC connector is the closest thing there is to a “standard” for sync cables.   Note this has nothing to do with “personal computer” it is simply the type of cable connector.   Some flashes have built-in PC ports for a PC cable to plug into, and some camera bodies do as well.  (pic shows the PC socket on a canon 580ex II) If you are lucky enough to have both a camera and flash with PC sockets - congratulations, simply get a PC cord, plug one end into the camera, one end into the flash and voila!  your (manual) flash is now connected just as if it were in the hotshoe.   Of course not all flashes and camera bodies have built in PC sockets, so what happens when we want to connect PC-socket-less cameras and strobes together?

Well, the camera still has a hotshoe and the flash still has a foot with that center “firing pin” in it, so we get ourselves some adapters.  One sits in the camera’s hotshoe, and one connects to the flash’s foot (a hotshoe adapter)   We can get these adaptors in various “flavors” with different connectors.  The most straightforward ones will simply have a PC socket.  So in essence you are simply adding a PC socket to your camera and flash via the hotshoe/foot.  Connect the 2 adaptors with a PC cable, just as you would with built-in sockets and again you’re good to go.  The fire pulse goes from the camera’s hotshoe, through the adapter, down the PC cable, through the adapter on the flash’s foot connects with the center pin, and pop goes the weasel! The beauty of this is that it will work with any camera/flash combination since it is just making the connection through the hotshoe (on camera side) and foot (on flash side).  The camera doesnt care what flash you are using - it just sends it’s pulse regardless, and you can stick any flash you want in the shoe adapter at the other end, and it will fire since it’s just getting it signal through the foot just as it would on camera.  Here are a couple of examples of hotshoe adapters with male PC and femae 1/4″ phono receivers:

Now personally I *hate* the PC standard.  Hate it, hate it, hate it.  I think the connectors are badly designed, fragile, and have a tendency to get damaged/bent out of shape or come loose at inopportune times.   I dunno, maybe it’s just me. PC is generally the “accepted standard” so, if you are just starting out, it’s probably easiest to go with, since it’s rather ubiquitous.

The Household connector (HH) is an alternative to the PC cable.  It functions exactly the same, except the physical connectors are different.  The HH cables actually use the same 2 prong connector as a standard US electrical cord.  I feel this is a much more robust and reliable connection personally, but I know that is arguable.   The cool thing about the HH standard is that you can use ordinary household extension cords to extend/split your cable if needed.   The downside to them is that there are no cameras or flashes (AFAIK) that have a HH port built in so you always need an adaptor on your flash’s foot and camera’s hotshoe to provide the necessary connector.  I personally have a nice little HH cable that has a built in adaptor that fits into my camera’s hotshoe on one end and a standard HH prong on the other end.  I slide the former onto my camera and plug the latter into an adaptor for my flashes foot and I’m good to go.  (see below)

So when it really comes down to it, all you have to do to fire *any* flash off camera with a sync cable is:

• stick an adapter in your camera’s hotshoe
• stick an adapter on your flash’s foot
• connect the two with a cable.

The 1/8″ and 1/4″ connectors are generally used with wireless transmitters, so now lets talk a bit about wireless transmitters and manual flash.

The good news is that if you get the whole business with the adapters/cables this will be easy.  Wireless transmitters are accomplishing the exact same thing (getting the “fire” pulse from camera to flash) they just do it a bit differently.  There are a number of transmitters out there, the primary ones being the ubiquitious pocketwizards, along with the elichrom skyports and the so-called “ebay triggers”.  The thing is *they all do the exact same thing*  In essence there is no difference between the $200 pocketwizard and the $25 ebay trigger other than range reliablity (although that is a big difference - once you’ve torn your hair out after having 50% of your shots not fire due to a flakey ebay trigger, $200 will seem like a small price to pay for rock-solid reliablity) (16 channel ebay trigger shown: note the contact on the transmitter that connects to the center pin of the cameras hotshoe)

But I digress… in essence they way all wireless triggers work is that there is a transmitter that attaches to your camera and a recieciever that attaches to your flash.  Just as with a cable, when you click the trigger your camera still sends that “fire” pulse - only this time it goes into the wireless transmitter.  The transmitter says “aha, I see a “fire” pulse” and sends a RF (radiowave) signal to the reciever (attached to the flash).  The reciever gets this signal, and goes “aha, the transmitter told me that the camera just sent a “fire” pulse” and then the reciever generates it’s own pulse, which goes to the flash.  The flash pops, and bob’s your uncle…  (this all happens in milliseconds).

Of course the “gotcha” with the wireless is that just like a cable, they need some way of connecting to your strobe.  Generally the wireless transmitter (whether pocketwizard, skyport or ebay) sits directly in the hotshoe of your camera, and connects directly to the center pin, so there is generally nothing needed on that end.  The receiver, however needs to be connected to the flash somehow.  Fear not, though - it’s basically the same procedure as with a cable.  You simply need a short cable that goes from the wireless to either the PC port directly (if your flash has one) or a hotshoe adaptor with a PC port in it.   Pocketwizards and Skyports have a 1/8″miniplug connector (same as a normal headphone jack on a portable audio device), and actually come with a little 1/8″ to PC cord (meaning a 1/8″ miniplug on one and and a PC connector on the other - See below)  in that case all you need is a hotshoe adaptor for the flash foot that has a PC socket and you’re good to go.  I didn’t have a pocketwizard to illustrate, but the 16ch ebay transmitter happens to have the same socket as a PW, so just pretend it’s a pocketwizard in the picture!

The ebay triggers are slightly different - they come in 2 flavors, the 4 channel and the 16 channel.  The 4 channel have the advantage of actually having a hotshoe built in, so they attach straight to the flash foot, no cables required!  The 16 channel use a 1/4″ phono plug connector, but they also have a PC socket on the back (which tends to be kind of flakey) so you can either connect them to a hotshoe adapter with a pc socket (using a short PC cable) or you can get a hotshoe adaptor that takes a 1/4″ phono plug directly.  Best place I’ve found is www.flashzebra.com.  The guy who runs it, Lon, is a really fantastic guy and has pretty much any adapter you can think of for conecting cameras and strobes, particularly “specialty” ones like the 1/4″ phono hotshoe adapter for use with the 16 channel ebay triggers.  (direct link to product here).  Check it out for all your crazy flash-connecting needs.

16ch ebay receiver and hotshoe adapter with 1/4″ phono from flashzebra:

Anyway, that’s pretty much it - hope that clears up some of the confusion regarding hooking up strobes for manual flash!  Stay tuned for next time when we will talk about wireless TTL!

P.S.  I should also mention that there is a 3rd way to trigger a manual flash, namely “Optical slave mode”  Not all flashes have this capability but for those that do it basically means that the strobe will fire whenver it “sees” another flash with it’s optical sensor.  This can be useful for example if you fire one flash with a camera and have a second one in optical slave mode.  The second flash will “see” the flash from the first one and fire itself. The dowsides to this are 1) it will fire whenever it sees *any* flash so if there are other folks around using cameras with flash, they will be setting it off as well 2) it requires the strobe be able to “see” the burst of light from the first flash, so it becomes unreliable in bright sunlight and finally 3) it will not work in combination with wireless TTL flashes (more on that in part 3)

CONTINUE WITH PART 3 HERE