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Assembly and Operating Instructions for HiViz.com Kits

 

Operating Instructions for the Multi-Trigger Breadboard, v11

 

Assembly instructions for other kits

 

 

Multi-Trigger with cables

 

 

Click on any photo for a larger version.

 

 

Overview

 

The Multi-Trigger Breadboard contains as many as 3 trigger modules, a sound trigger, a photogate, and a delay timer. Some people will have assembled all three modules and others one or two. The operating instructions to follow are organized so that one can concentrate on the instructions for their particular module(s). The sections are identified according to which module(s) they refer to. As a result of this organization, you'll find some duplication of instructions.

 

Sound Trigger

Photogate

Delay Timer

Triggering a Camera Shutter

Open Shutter Photography

Summary of Breadboard Connections

 

Photo 1

Battery cable connection (all modules)

 

Refer to Photo 1 to the left. The entire horizontal line of holes on the bottom of the breadboard along the blue line is negative (ground). Likewise, the entire line of holes along the red line on the top is +9 V. Connect the red and black wires from the battery clip to the 9V (red) column and the ground column (black) as shown in Photo 2 to the right. Note the two wires could just as well be connected on the opposite of the breadboard.

Photo 2

 

Replacing components

Due to the nature of an open circuit on a breadboard, components may become dislodged and need to be reseated. Step-by-step instructions showing placement of components can be found in the assembly instructions. Replacement parts are available in the HiViz.com online store.

 
  Sound Trigger  

Photo 3

Microphone connections

 

As shown in Photo 3, the breadboard wires connect to pins M and G on the piezoelectric disc, which serves as a microphone. There is no connection to pin F. Photo 4 shows the connections to the breadboard. These are given below.

 

Connection
Microphone Breadboard
pin G ground
pin M A26

Photo 4

Photo 5

Flash unit connections

 

The flash trigger cable shown in Photo 5 is used to connect to a flash unit.* (Cable kits can be purchased here.) The cable connects either to the flash unit or a hot shoe adapter with a standard PC plug. Photo 6 shows the connections to the breadboard. These are given below.

 

Connection
Cable Breadboard
red A30
black ground

 

*Triggering a wireless controller is an alternative method. Connect the controller to the same breadboard holes as for a flash unit. Keep in mind that the controller may introduce a delay of a few milliseconds. This would be too great to capture a balloon burst. For the most rapid response, trigger the flash unit through the PC cable or hot shoe.

Triggering a camera shutter is another possibility if you're not concerned about the delay created by the inherent shutter lag of the camera. In order to trigger a camera shutter, see this information.

Photo 6

Photo 7

Sound trigger operation

 

Turn the yellow potentiometer knob all the way counterclockwise. Then turn it clockwise three-fourths of a turn. Connect a fresh 9-V battery to the battery clip and turn on the flash unit. A finger snap or a tap on the piezo disc should set off the flash immediately. The only delay is the amount of time it takes sound to travel from the source of sound to the microphone. That's about a thousandth of a second per foot (30 cm) of distance. At this point you're ready to capture photos. See this section for information on open shutter photography.

 

Adjusting the sensitivity: Continuing to turn the yellow pot clockwise will decrease the sensitivity somewhat. Note, however, that if you turn the pot too far counterclockwise, the flash will not discharge. In this case, simply turn the knob clockwise until you can get the flash unit to discharge.

 

Using a delay timer with the sound trigger: Rather than setting delay times by distance as described above, you can use the delay timer module of the Multi-Trigger. This can be convenient when the delays that you need are relatively long. Another reason to use the delay timer is to use its timeout feature. This can suppress multiple discharges of the flash unit due to echos. In order to use the delay timer with the sound trigger, you need to connect a trigger wire. See Photo 7. The trigger wire is the green wire connected between D30 and F13. Important: When using the delay timer with the sound trigger, do not connect a flash unit to A30. Instead, make connections to a delay timer output as described in the Delay Timer instructions.

 
  Photogate  

Photo 8

Photogate cable connection and alignment testing

 

The variable-width photogate cable has three wires for connecting to the breadboard. Make connections as shown in Photo 8 and the table below. If you're using an interrupter cable, the connections are the same.

 

Connection
Wire Breadboard
red 9V column
green J3
black I8

 

As a test of alignment, orient the emitter and detector as shown in Photo 9. Turn the sensitivity (brown pot) to its halfway position and connect a battery. With the emitter and detector aligned, the red LED of the photogate circuit will light and remain lit as long as the infrared beam in unblocked. When you block the beam with a finger, the red LED will go out, indicating a triggering event.

Photo 9

Photo 10

Flash unit connections

 

The flash trigger cable shown in Photo 10 is used to connect to a flash unit.* (Cable kits can be purchased here.) The cable connects either to the flash unit or a hot shoe adapter with a standard PC plug. Photo 11 shows the connections to the breadboard. These are given below.

 

Connection
Cable Breadboard
red A10
black ground

 

*Triggering a wireless controller is an alternative method. Connect the controller to the same breadboard holes as for a flash unit. Keep in mind that the controller may introduce a delay of a few milliseconds. This would be too great to capture a balloon burst. For the most rapid response, trigger the flash unit through the PC cable or hot shoe.

Triggering a camera shutter is another possibility if you're not concerned about the delay created by the inherent shutter lag of the camera. In order to trigger a camera shutter, see this information.

Photo 11

Photo 12

Photogate operation

 

With a flash unit connected to the breadboard, the flash should discharge when the photogate beam is blocked. Depending on the ambient light level and the separation of emitter and detector, the sensitivity may need to be adjusted. Adjust as needed in order to maintain the circuit in a ready state when the beam is unblocked (that is, the state in which the LED is on).

 

At this point you're ready to capture photos. See this section for information on open shutter photography.

 

Using a delay timer with the photogate: It's common to use a delay timer with the photogate. In order to connect the photogate to the delay timer, connect a wire from E10 to F13 as shown in Photo 12. For information on how to use the delay timer, see the next section of these instructions. Important: When using the delay timer with the photogate, do not connect a flash unit to A10. Instead, make connections to a delay timer output as described in the next section.

 
  Delay Timer  

Photo 13

Triggering and testing the delay timer

 

A short circuit from F13 to ground is required to trigger the timer. Photo 13 shows how this can be done with a wire jumper. When the green wire is connected from F13 to ground, the delay sequence is initiated. This is effectively what happens when a sound trigger or photogate is connected to F13. These connections have been described previously in the Sound trigger operation and Photogate operation sections above and shown in Photos 7 and 12. Another option is to use a contact trigger. In fact, any trigger that has as its output a simple circuit closure will work with the delay timer.

 

Before describing the delay timer controls, here is a brief theory of operation. Refer to the graphic to the right. The delay circuit responds to the triggering event by producing two output pulses with a delay interval between them. Output Pulse 1 is shown as the middle line in the graphic. This is a square pulse whose duration depends on the settings of the coarse and fine delay knobs (enclosed in a blue box in the photo to the left). At the end of Output Pulse 1, a second square pulse is produced, Output Pulse 2. This second pulse remains high for a length of time determined by the value of the timeout resistor (enclosed by a yellow box in the photo). During this time, the trigger LED (circled in green in the photo) is on, indicating that the timer was triggered. The two output pulses trigger devices such as a flash unit or camera by making appropriate connections to the breadboard. The instructions to follow will show how to make these connections and how to adjust the delay and the timeout intervals.

 

As a test, connect a 9-V battery to the battery clip. Turn the blue delay knob to its full clockwise position. Connect a 2-in wire to F13. Touch the other end of the wire briefly to ground. You should see the trigger LED flash after a delay of about half a second.

Photo 14

Adjusting the delay and changing the delay range

 

The blue and brown potentiometers enclosed by the blue box in Photo 13 are used as variable resistors to set the delay. The blue, 1-MΩ potentiometer provides coarse delay adjustment, while the brown, 100-kΩ potentiometer provides a finer adjustment. Once you've set the delay approximately using the 1-MΩ potentiometer, use the 100-kΩ potentiometer to make finer adjustments. The further clockwise that you turn either potentiometer, the more of a delay there will be. You'll notice the delay as the time interval between connecting the jumper wire from F13 to ground and the flash of the red LED. If a flash unit were connected to the delayed output of the unit (more about this later), the flash would discharge after the delay that you dialed in.

 

Normally, the range of the coarse delay is 0 to 0.5 second and that of the fine delay, 0 to 0.05 second. However, it's possible to divide both of these ranges by 10 for situations in which much shorter delays are needed. This is accomplished by replacing the 0.47-µf capacitor (circled in green in Photo 14) with the extra 0.047-µf capacitor provided in the kit. The connections of the legs are the same for both capacitors, H23 to H25. Note that the 0.047-µf capacitor does not have polarity; therefore, it doesn't matter which leg goes in which hole. When replacing the 0.47-µf, however, make sure that the negative leg goes in H25. This is the side with the light-colored band.

 

 
 

Adjusting the timeout

 

After the delay unit triggers, it will be inactive for a short time before it can be triggered again. This amount of time is called the timeout. Normally, the timeout is about a hundredth of a second, less than the recharge time of many flash units. The timeout is determined by the value of the resistor enclosed by a yellow box in Photo 14. This 1-kΩ resistor can be replaced by the extra 100-kΩ resistor provided with the kit. The effect will be to multiply the timeout by about 100, giving a time interval of about 1 second. A typical use of the timeout is to eliminate multiple exposures that may be produced by events that produce prolonged or multiple sounds. For example, if you're smashing glass, the initial breakage will produce one exposure while the sounds of glass hitting the table may produce additional exposures. If you set the timeout to a second, you'll get just one exposure.

 

Note that the timeout function applies to the delayed output of the timer, not the instant output.

 

Photo 15

Flash outputs

 

The flash trigger cable shown in Photo 10 above is used to connect to a flash unit.* (Cable kits can be purchased here.) The cable connects either to the flash unit or a hot shoe adapter with a standard PC plug. There are two possible connections, instant and delayed. When connected to the instant output, the flash discharges immediately when the delay timer is triggered. When connected to the delayed output, the flash unit discharges after the amount of time set by the delay pots and capacitor as described previously.

 

Flash units may be connected to the instant and delayed outputs at the same time in order to produce two flashes of light a short time apart.

 

Connection
Output

Red

(positive)

Black

(negative)

Photo

reference

instant A11 ground Photo 15
delayed A15 ground Photo 16

 

*Triggering a wireless controller is an alternative method. Connect the controller to the same breadboard holes as for a flash unit. Keep in mind that the controller may introduce a delay of a few milliseconds. This would be too great to capture a balloon burst. For the most rapid response, trigger the flash unit through the PC cable or hot shoe.

Triggering a camera shutter is another possibility if you're not concerned about the delay created by the inherent shutter lag of the camera. In order to trigger a camera shutter, see below.

Photo 16

Opto Switch 2

Triggering a Camera Shutter

 

In order to trigger a camera shutter, you'll need an Opto Switch 2, shown to the left. This module provides a protective stage between the trigger circuit and your camera. Two cables are needed to connect to the output and input of the Opto Switch 2. The output cable is the remote shutter cable for your camera. We have shutter cables available here. The input cable is a standard male-to-male RCA cable (supplied with the Opto Switch 2), but you'll also need the adapter shown to the right to connect to the breadboard. This can be purchased as an add-on to the Opto Switch 2.

 

The connection points of the Opto Switch 2 to the breadboard are different than those for flash units. See the table below for the Opto Switch 2 connection points for the three modules of the Multi-Trigger Breadboard.

 

Trigger module Time delay Connections
Positive Negative
Sound trigger* instant A27 ground
Photogate instant A3
Delay timer instant B16
delayed D18

*You must also disconnect the wire from D27 to D29.

 

It's possible to trigger both a camera and a flash using the Multi-Trigger Breadboard. If the camera is connected to the instant output (via an Opto Switch 2), and the flash unit is connected to the delayed flash output, then the camera shutter can be opened automatically before the flash unit discharges. This is useful, for example, in photographing drops and splashes.

 

 

Open Shutter Photography
While HiViz.com triggers can actuate camera shutters, a more common application is to trigger flash units. There are two reasons for this. The first is that a flash unit can respond much more quickly than a camera. The shutter of a camera has an inherent lag. For many situations, the high-speed event of interest is over before a camera shutter can open. Such is the case for a balloon burst by a needle. A typical burst lasts only a few milliseconds, and this is less than the time that a typical camera shutter acts to open. The second reason is that the duration of the flash can be set very short in order to “freeze” high-speed events. Durations as short as 1/20,000 s are typical.  For information on the selection of a flash unit for high-speed photography, see this article.


The technique of capturing a high-speed event with short-duration flash is called the open shutter technique. The method has the following steps:

  1. Connect the flash unit to the trigger rather than to the camera. The camera is independent of the flash.
  2. Make all camera settings in manual mode, and position the camera on a tripod or other support.
  3. Turn out the room lights and open the camera shutter in bulb mode or for an exposure of a second or more, long enough to initiate the high-speed event.
  4. Initiate the high-speed event. The flash will fire in response to the triggering event. Once the flash fires, close the shutter and turn on the room lights.
  5. Examine the photo. Then adjust timing and positioning as needed to improve the photo.

 

Summary of Breadboard Connections

 

Cable connections

 

Trigger module Time delay Output type Connections
Positive Negative
Sound trigger instant flash1 A30 ground
camera2,3 A27
Photogate instant flash1 A10
camera2 A3
Delay timer instant flash1 A11
camera2 B16
delayed flash1 A15
camera2 D18

 

1Use the same connections for a wireless controller.

2The use of the Opto Switch 2 is assumed.

3You must also disconnect the wire from D27 to D29.

 

Trigger to delay timer connections

 

Trigger Trigger output Delay timer input
Sound D30 F13
Photogate E10 F13

 

 

 


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