Methods to Trigger the Flash Off Camera - TTL or Manual Flash

Trigger Methods for Off Camera Speedlights

(Manual flash mode, see BELOW )

Triggering Automatic TTL flash

Bounce Flash with Hot Shoe flash

This is hot shoe flash, not off-camera of course, but it is not direct flash either. A speedlight fits the camera hot shoe, which then triggers with the shutter button, in either digital iTTL or manual flash mode. The hot shoe is not the best location for a flash, but it can be very effective there too, particularly if used as bounce flash from ceiling or wall. Bounce flash eliminates the flat frontal lighting of direct flash (sort of like off camera.) Bounce flash is an easy thing to do to improve your flash, and is also among the best things... Bounce should always be your standard method for a hot shoe flash, if there is any suitable ceiling or wall present.

Nikon Commander/Remote Wireless Remote System

The Commander system is the only means of multiple iTTL flashes. All other iTTL is one flash only, connected to the hot shoe.

The Nikon Commander could be the internal popup flash of camera models with commander. Nikon D40/D50/D60 and D3100/D5100 do not include a commander, but models D80/D90/D200/D300/D7000/D700 do. Or it could be an added $250 Nikon SU-800 Commander, or it could be a SB-700, SB-700, SB-900, or SB-910 flash (on the hot shoe, operating as Commander.) The commander must be on the camera, or attached with the hot shoe extension cord.

The commander flash can also contribute to your lighting, or not. Your choice, the commander menu has a "- -" choice to disable it. Even when disabled, the commander WILL FLASH commands before the shutter opens. With the commander and a couple of remote flashes, this is a very impressive system, allowing automatic wireless remote point&shoot TTL multiple flash. There are also a few downsides not encountered with manual flash. Much preflashing occurs which causes subject blinking, but camera FV Lock is a work around (however camera models without commander do not implement FV Lock.) See a similar discussion of these differences of Commander vs Manual. See a brief descripton of this Nikon AWL system (for automatic point&shoot remote wireless multiple TTL flash.)

Pros of Nikon Commander:

• Can be automatic point&shoot wireless remote multiple TTL flash. What else can do this? Don't be overwhelmed by the Cons, this can be a really excellent system. However, there are a few little details.
• Remote flashes are controlled from the camera position.

Cons of Nikon Commander:

• Optical trigger
  - Requires direct line of sight, no obstacles (reflection sometimes possible at short range indoors)
  - Relatively short range - normally adequate
  - Bright sunlight can interfere
  - Works pretty fine indoors. All of this can be solved by radio triggers, however radio triggers are typically manual flash mode only - a great difference.
• Limited to only two or three individually controllable lights (main/fill/background/hair is four - no workaround.) However, probably would not use speedlights in a serious studio situation.
• So-called commander manual power setting is NOT the same as real Manual mode - it is fully incompatible other optical slave flashes.
• Slight shutter lag time. FV Lock is a workaround.
• All that flashing before shutter opens causes photos of the subject blinking. This is surely the worst problem. Not every person blinks, but many do. Some few blink from one iTTL preflash on the hot shoe. SU-800 prevents this from the commander, but the remotes still preflash. FV Lock can bypass it, and also keep the exposure from being remetered differently at every frame.

We cannot mix and match Manual flash gear with the Nikon Commander system. Digital camera flash is simply very different than the old days. Optical slaves are simply incompatible with all the preflashing done by the commander system (a Sekonic flash meter can be used with Commander manual mode, **IF** the commander is the SU-800, or if the Nikon SG-3IR infrared panel is used on a camera commander) -- and **IF** the meter is not closer than 5 or 6 feet to the infrared commander (may get EU errors if closer.) The preflashing will trigger your slaves too early, before the shutter opens, and thus they cannot contribute to your picture lighting. You can use the Commander system, or you can use the Manual system. Just pick one system and go with it, then no problems.

Hot shoe extension cable:

This is Nikon SC-17, SC-28, SC-29 cables.

On this hot shoe extension cord, the flash can use any mode it can do on the hot shoe, but the cable only controls one digital TTL or Manual mode flash, or a commander. These cables work well with a hand held flash, just about the right length at arms length. They are coiled cords, and may technically stretch to perhaps five feet, however they are actually limited to about 2 feet, because if stretched longer, the coil tension is tight, and probably will turn over your light stand or camera tripod. The loose stand sitting on a table is NOT going to work this way, you will have to anchor it down.

The older Nikon SC-17 cable still works fine, and is plentiful and inexpensive on Ebay. This older SC-17 is the same cable as the newer SC-28, except it does not have the pin hole for the hot shoe lock of the new flashes (which the new SC-28 does have.) The old SC-17 still works fine however, just lower the pin and the flash will not fall out, or you can easily drill that hole. I went a few years without the hole in my old cables, and then finally got around to drilling it. Really does not matter.

The SC-29 has an additional AF Focus Assist light at the camera end. The speedlight already has a focus assist light to help focus in dim light, however when off camera, it probably is not be aimed at the precise focus point the camera needs. The SC-29 adds another focus assist light in the hot shoe, which will always be aimed directly forward, where the camera needs it. This is only needed in the nearly dark places when focus is not otherwise possible. If it is otherwise bright enough to focus, then it is bright enough to focus, and is unneeded.

You can chain up to three of these cables to be a little longer. Each is an extension cord. Or, there are other brand cords which are longer. Or, you can heat the old (inexpensive, expendable) SC-17 in hot water, and straighten out the coils into be an almost straight cable perhaps 8 feet long. A bit kinky and ugly, but it should work well.

Triggering Manual flash trigger methods (Speedlights or studio units)

(Manual flash mode only - no automatic TTL possible these ways. These accessories can connect to flash unit via short PC sync connector cord, or via a foot mounted accessory adapter, of the types below.)

PC sync cable:

You can add the Nikon AS-15 hot shoe adapter to add a PC sync connector to a camera which does not have one (very handy substitute on a camera with PC too, unless you have a PC cord with Screw-Lock, to be tighter in camera PC.) The AS-15 is a particularly good one, has the clamp to keep it from sliding off center. Then you can use a PC Male to PC Male sync cable (getting hard to find) from the AS-15 to a Nikon SB-800 or SB-900 (the SB-600 and SB-700 have no PC sync connector, however third party PC adapters can be added to its foot.) Studio lights have a different connector at their end, but whatever cable fits your light, you would use that same PC sync cable to a handheld flash meter too (to meter that light.) A PC Male to PC Female cable is an extension cord for any of them. This PC sync cord method is only Manual operation, no TTL. There are three-way Y adapters to split and run cables to multiple flashes, but you would probably prefer to run a sync cable to the nearest flash, and its flash will trigger the other flashes equipped with optical slave triggers.

Radio trigger:

Popular, IMO, on hand held cameras.

A transmitter module goes in the camera hot shoe, and a receiver module attaches to the flash, usually via PC sync connector, or some models use a shoe foot connector. Radio has advantage of great range, will go through/around most obstacles, and is not affected by bright sunlight - so only choice in some extreme cases. Involves a few extra parts, extra connections, extra batteries. Receiver battery requirement is high, because the receiver always must be listening.

Radio triggers are a mixed bag. There are expensive ones that are very reliable, and there are many less expensive imports that may be a little less reliable (about triggering every time.) Virtually all are simple Manual flash mode triggers, but Radio Popper and Pocket Wizard each have one model that simply relay the Nikon commander system via radio, with the same features and issues then, except radio is not limited in the way of optical triggers.

Optical slave trigger:

Popular, IMO, in the studio.

An added accessory, usually added at the flashes PC sync connector, or some fit the flash shoe foot, which triggers the flash in sync when the light from another manual flash is detected. Some other Manual mode flash does have to flash to trigger it. Most studio lights include this optical slave trigger builtin, and they routinely operate this way. We trigger the first nearest light some other way, like with a sync cord or radio trigger (or with camera internal flash set to minimum Manual power level), and then that light from the first one triggers all the others. The Nikon commander system above is VERY different, in that it uses a special complex trigger signal at minimum power level, but this optical slave uses the regular full working power flash from any other manual flash, so reliability can be very good. Range is not extreme, but these work great in a studio environment. Downside is that any other photographer using flash in same room will trigger your lights too. Manual flash only.

The SB-700, SB-800, SB-900, SB-910 already contain built in slave triggers (called SU-4 mode, next below.) SB-600 performance has been spotty with added optical triggers. The slave triggers contain no battery, and are powered by the sync voltage of the flash unit. The SB-600 sync voltage is only around 3.3 volts, a little low for this, and slave performance cannot be predicted. In that regard, see a selection of a few Optical Slave Triggers from Ebay.

Optical slave triggers are incompatible with digital TTL flash mode. The digital preflash will trigger them too early to contribute, before the shutter opens. Generally, all flashes involved must be in manual flash mode. However, there are "digital" slave triggers which can ignore the hot shoe digital TTL preflash, BUT these still CANNOT ignore the commander flashing (still incompatible with Commander.)

SU-4 mode:

This Nikon mode is simply an excellent built-in optical slave trigger. The actual Nikon SU-4 is a shoe foot optical slave trigger device (which can be added.) The Nikon SB-700 to SB-910 flashes (NOT the SB-600 or SB-400) include this internally, with the menu to set them into SU-4 mode, where they become an optically triggered slave, such that the light from any Manual flash will trigger them. They will work well with studio lights this way, they become just another optically triggered slave flash. Repeating, the actual Nikon SU-4 is a separate slave trigger module for flash foot. The older Nikon SB-26, SB-50DX and SB-80DX models also include a builtin internal optical slave trigger (manuals here.)

One flash does have to be triggered to flash some other way, in order to trigger the optical slaves. This could be your pop-up flash, set to Manual mode, and set to lowest manual power - to not affect your picture much, if at all. This low power pop-up is not going to do much to your picture, except at very close subject distances. The main flash will be much stronger. The SU-4 mode flashes are quite sensitive, and 1/128 power from 60 feet away will trigger them, IF their sensor is pointing at the source. Probably more, but 60 feet is the longest I have tried. In an indoor studio situation, with the high power main light triggering them, random wall reflections work well and line of sight seems no issue. This is Manual flash mode, no TTL. There is an Auto mode, where the flash meters and controls the flash itself, if the ISO and aperture used by the camera is specified.