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This device will trigger a camera or flash unit to automatically take a picture when an object (target) enters a specific location. It uses two, crossed infrared light beams to detect the presence of the target and close a relay that trips the camera or flash unit. Response time is about 2 ms from detection to relay closure, so if your camera doesn't have long shutter-lag, it will capture even fast moving targets.
The optical part of the device consists of two IR LEDs and two Sharp IS471FE optical ICs (OPICs). The optical ICs have built in LED modulators and synchronous detectors, so they won't see light from each other's LEDs. The outputs from the OPICs are connected to an 8 pin PIC microcontroller that handles interpreting input signals and driving the relay and a visible LED that indicates the operating mode. Though there are 11 operating modes, the controller has a very simple user-interface consisting of a pushbutton switch and an LED.
On power up if the beams are properly aligned and unbroken, the LED lights continuously for 1 second then goes dark to indicate the unit is ready to operate in the continuous mode. In that mode the relay will close and remain closed and the LED will light up as long as both IR beams are interrupted. The unit is now ready to connect to your camera.
With some targets you may want to take more than one picture when the target breaks the IR beams. I have included a basic intervalometer function in the controller to allow cameras that don't have a built-in rapid-fire mode to take multiple pictures as long as the IR beams are interrupted. Pushing the mode select button once takes the controller out of continuous mode and puts it in pulse mode. The LED will flash one time to indicate that the relay will close 1 time per second. Some cameras are faster so pushing the button again will move up to 2 pulses per second. By repeatedly pushing the button, the speed will increase from 1 pps all the way to 10 pps, each time flashing the LED to indicate the pulse frequency. Holding the button down for 2.3 seconds resets the unit and takes you back to continuous mode.
The optical part of the device consists of two IR LEDs and two Sharp IS471FE optical ICs (OPICs). The optical ICs have built in LED modulators and synchronous detectors, so they won't see light from each other's LEDs. The outputs from the OPICs are connected to an 8 pin PIC microcontroller that handles interpreting input signals and driving the relay and a visible LED that indicates the operating mode. Though there are 11 operating modes, the controller has a very simple user-interface consisting of a pushbutton switch and an LED.
On power up if the beams are properly aligned and unbroken, the LED lights continuously for 1 second then goes dark to indicate the unit is ready to operate in the continuous mode. In that mode the relay will close and remain closed and the LED will light up as long as both IR beams are interrupted. The unit is now ready to connect to your camera.
With some targets you may want to take more than one picture when the target breaks the IR beams. I have included a basic intervalometer function in the controller to allow cameras that don't have a built-in rapid-fire mode to take multiple pictures as long as the IR beams are interrupted. Pushing the mode select button once takes the controller out of continuous mode and puts it in pulse mode. The LED will flash one time to indicate that the relay will close 1 time per second. Some cameras are faster so pushing the button again will move up to 2 pulses per second. By repeatedly pushing the button, the speed will increase from 1 pps all the way to 10 pps, each time flashing the LED to indicate the pulse frequency. Holding the button down for 2.3 seconds resets the unit and takes you back to continuous mode.
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Signing UpStep 1Gather Electronic Parts
Here are the parts lists for the electronic stuff.
All of the electronics can be obtained from Digikey or other sources. You will need a bunch of different colors of wire, too.
You will need to be able to program the PIC microcontroller- a PICKit2 or ICD-2 or any of hundreds of other programmers can do the job. A suitable programmer will cost about $20, but once you have it you will find all sorts of projects that can use microcontrollers and will get a lot of use out of it.
When I bought my PICKit2 from digikey I ordered an accessory pack of five PIC10F206 chips with 8 pin DIP adapters. The IC is in a tiny SOT23 package which is fine if you're going to make a PCB but pretty useless for breadboarding and one-off construction projects. The 10F206 is also available in an 8 pin DIP package- I suggest you use it.
I have not provided PCB layout info for the controller here because I didn't use a PCB. The circuit is so simple that it seems sort of silly to make a PCB for it. There are only 4 parts on the board- the relay, the uC, the bypass cap, and a resistor. The circuit requires fewer parts than a 555 timer chip circuit. Just cut some perf board to fit whatever box you're using and wire the thing up. It should take all of 30 minutes start to finish.
The optical circuits are pretty simple- an IC, a cap, and a LED. The LED and optical IC go into diagonally opposite corners of the pipe frame, so you're going to need a bunch of colored wire. I "assembled" the IC and capacitor on small pieces of perf board that fit into cap-plugs for the PVC elbow fittings in the frame- see photos on the next page.
All of the electronics can be obtained from Digikey or other sources. You will need a bunch of different colors of wire, too.
You will need to be able to program the PIC microcontroller- a PICKit2 or ICD-2 or any of hundreds of other programmers can do the job. A suitable programmer will cost about $20, but once you have it you will find all sorts of projects that can use microcontrollers and will get a lot of use out of it.
When I bought my PICKit2 from digikey I ordered an accessory pack of five PIC10F206 chips with 8 pin DIP adapters. The IC is in a tiny SOT23 package which is fine if you're going to make a PCB but pretty useless for breadboarding and one-off construction projects. The 10F206 is also available in an 8 pin DIP package- I suggest you use it.
I have not provided PCB layout info for the controller here because I didn't use a PCB. The circuit is so simple that it seems sort of silly to make a PCB for it. There are only 4 parts on the board- the relay, the uC, the bypass cap, and a resistor. The circuit requires fewer parts than a 555 timer chip circuit. Just cut some perf board to fit whatever box you're using and wire the thing up. It should take all of 30 minutes start to finish.
The optical circuits are pretty simple- an IC, a cap, and a LED. The LED and optical IC go into diagonally opposite corners of the pipe frame, so you're going to need a bunch of colored wire. I "assembled" the IC and capacitor on small pieces of perf board that fit into cap-plugs for the PVC elbow fittings in the frame- see photos on the next page.
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CPU 16Mhz Atmega 328
84x48 graphic LCD with backlight
IR & Wire Photo camera trigger
2x Wire Flash Trigger
onboard light/sound sensor or 2x external sensor
2x digital IN/OUT
timelapes function
onboard RTC clock
onboard buzzer
http://www.facebook.com/home.php#!/pages/APCC-Advanced-Photo-Camera-Control/194425487264052?sk=info
I am hoping to use it to detect water drops, but not in the cross beam setup. I want to use beams separately, one to trigger the camera shutter (1 sec exposure) then another below to fire the flash. As the water drop hits the first the shutter opens, then when it passes the second it will trigger the flash (after a pre set delay).
I will not be using the pic circuit just the emitter/ detectors wired into Arduino inputs.
I am also rather interested in the macro aspect, the possibility of setting it up in cross beam to capture insects would be a very cool thing to play with given that macro is my 'bag' but would it have the resolution to capture the very small?
check out some of my macro work here if you have the time:
http://www.flickr.com/photos/louise-paisley/collections/72157606475942705/
I wish I was a better photographer, here are mine:
macro shots
<img src="http://lh6.ggpht.com/_ALPVWabsNTI/SuEMzx-56jI/AAAAAAAABFI/V1DeeS3HOJM/s144/Macro%20018.jpg">
Now, to answer your question, the beam that the LEDs produce is pretty wide, at least a few mm, so it might be difficult to get small objects like water drops to break the beams reliably. One solution would be to restrict the light path at the detector. I'd probably just use a couple carefully aligned pinholes at either end of short (maybe 10-20 mm long), blackened tube positioned in front of the detector. Keep the path from the LED to the detector short and it should work.
The same technique could be used to make a small. crossed beam set up for shooting bugs.in macro mode. Depth of field is often so narrow that it may be difficult to ensure that when the beams are broken the target is focused exactly where you need it to be. On the other hand, the beams may make possible shots that would otherwise be nearly impossible to capture, so I think it would be worth trying. Keep in mind the narrower you make the beams the harder it will be to align them.
The path of water drops can be controlled easily so you may be able to just set up two beams, one to trip the shutter and the other to fire a flash, without having to bother with crossed beams.
I look forward to seeing some of your pictures made using the new system.
Cheers!
I am probably doing something else wrong, I am very much a beginner in electronics lol. I am driving it with the 5v output of the Arduino and just feeding the output into a digital in to read the state so just used the sensor page schematic.
Would the absence of D2 & C1 have any impact?
http://gizmodo.com/341634/casios-exilim-pro-ex+f1-hands+on-1200-fps-demo-video-and-sample-60+shots+per+second-gallery
TD