Camera Trigger

[balint]

I am thinking of making a camera trigger, usefull for wild-life and high-speed photographers but, not only. I would like to ask for your feedback regarding the features of the trigger.

Below is a brief description of the features and functionality of the trigger. The trigger should consist of the following modules:

1. sensors - lasers, sound, lightning sensors
2. controller unit
3. mechanical actuators
4. connection cables with weather sealed XLR connectors

The controller unit will accept 2 sensors (inputs) and will be able to trigger 4 cameras (outputs) at once. It will have a nice 4x20 character backlit LCD display, and the whole thing would be weather sealed.

Each sensor will generate a trigger event (laser beam broken, sound level above a treshold ...) which is interpreted by the controller. The controller is checking it's triggering criteria, which can be a logic function: OR or AND (one of the laser beams or both beams broken), or a sequencial function: A->B (laser beam A broken than whitin 500ms, laser beam B broken too), or B->A.

After the triggering criteria is fulfilled, the controller will execute the triggering sequences for each on its outputs independently.

Most of the cameras today have an electronic shutter release (Nikon F5, F4, F100, F90), but since many high-speed photographers will use LF cameras, it will be possible to attach mechanical actuators to the outputs of the controller to trigger any camera.

What do you think, would there be a market for such a product. I am going to make at least one (for myself), but if anybody interested, let me know.

cheers

 

[Donald Miller]

You have obviously given a great deal of thought to this. I am not sure that I understand all about what you have written and for that reason I do have some questions. I will also give you my thoughts.

1. As I understand, you have two sensors controlling four cameras, why would you not have four sensors controlling those four cameras? How will your logic unit determine which of the cameras on a given sensor channel to fire? I once had a multifunction back on a 35 mm camera years ago and I did use it trip the shutter at some remote event. I did work up a nighttime skiing shot that utilized a sound trigger to fire strobes to expose and stop the skier with the background mountain lit by natural light, in that instance the device you envision would have been of appeal. If I were wanting to build something such as this I would build this as a modular unit in which I made available the logic unit, individual sensors, (sound, motion, light) and the control units so that the prospective purchasers would have the ability to decide what they wanted and needed. (More customization would appear to be appealing).

2. I work in large format and while I can't speak for all LF users, I would find this device to be of limited appeal to my applications. I don't use LF to do wildlife photography and the shutter speeds on the LF shutters do not lend themselves to high speed photography (unless one uses strobes). I would find this more appealing if I were shooting 35 mm or even possibly 2 1/4. It would lend itself to a camera system that had the availability of motor drive for film advance. (that is not the case with LF or even most MF).

If it were me and I had the idea that you have and had a burning desire to see where it would take me, then I would contact people like National Geographic for contact with their photographers. I would think that this would be appealing to those folks who spend interminable hours in swamps and jungles. It would seem to be more fun to hang around inside the tent and sip mint julips then to get my butt eaten off by mosquitos. Good luck, sounds like you have something there.

 

[balint]

Thanks for your thoughts. I would like to clarify the how the 2 sensors will control those 4 cameras with a simple scenario:

Say I want to capture a brown bear. Bears tend to follow the same routes, and so it is easy to set up a photo-trap and take some pictures. I would use 2 laser beams, set up so that they both cross the route of the bear.

On the control unit I would select a sequencial function A->B with a 1 second offset, which means that in case the laser beam A was broken and 1 second later laser beam B was also broken, the control unit will trigger the cameras. This way I can make sure that the bear is aproaching and not departing when trigger goes off.

I will use up to 4 cameras, to capture the scene from different view points. So all cameras are triggered whenever the trigger criteria is fulfilled, but the I will be able to set individual delays and trigger patterns (for instance: continous shooting at the camera's rate, single shot or say 7 shots with a 500 milisec period...).

The reason behind the 2 input 4 output architecture is simple. We need 4 plugs for the 2 sensors, as the lasers will need transmitter and receiver components. There are 4 outputs, simply for allowing the photographer to use multiple cameras for multiple viewpoints. This way we would have 4 input and 4 output plugs.

The XLR plugs I intend to use are faily big, but perfectly suitable for the task. The device would be something wich can be handheld, at least 12cm wide, so that the sensor plugs fit on the top side and the actuator plugs on the bottom side of the device.

We are still in the design phase and that's why we wanted to have some input what kind of features should we integrate into this device and to make some market research too

Thanks once more, if anybody else has something to say, I am very interested.

cheers,

 

[Aggie]

..

 

[Eric Rose]

I'm pretty sure the devices you are after are currently available. I have seen TV shows on nature photogs using these kinds of setups to catch pictures of dangerous animals. I am also pretty certain the security industry would have devices such as this as well. Maybe do some research and determine if you are reinventing the wheel.

 

[balint]

Indeed similar devices are currently available. I know about one manufacturer:
http://www.kapturegroup.com/
but their stuff is analog and incredibly overpriced. Since they have no concurence, they set the prices. If I would sell my digital trigger, it would be something around $700 including two laser triggers and cables. But I am not quite there yet to set prices.

Aggie, you dont need 4 cameras, that's just an option, which cost little but would be an advantage considering the current triggers. If someone wants to capture an event happening once in a lifetime, it's better to set up multiple cameras if you can afford. Many can; I know people owning 3 Nikon F5s among many others, with a bounch of lenses. Indeed protecting the cameras & lenses is a challenge but this is something photographers should sort out, considering the environment they work in.

Setting up the trigger would be as simple as setting up a digital alarm clock. I already designed the user interface and showed to some of the fellow people over here. They said that's transparent.

 

[Donald Miller]

Re: your laser sensors, would these require a sending and receiving unit? Would it not be possible to have your lasers incorporate a reflection device that would indicate a "go- no go" and depending on how you set the switching (SpSt No or Spst NC) configuration have the circuit either made or broken at your logic unit? Are you thinking of a RC circuit to read the sensors and the same to trigger the camera(s) or are you considering RC on only the camera(s)?

 

[Robert Kennedy]

Instead of laser why not go with a simple IR beam like they use in stores to indicate foot traffic? Cheaper and simpler by far.

I would also suggest contacting the Arizona Department of Fish and Game at http://www.gf.state.az.us .

They have been using remotely triggered cameras to track the movements of Jaguars in SE Arizona. Yes, we have Jaguars here. They used to roam as far north as the Grand Canyon. While thought extinct in the state, in the late 90s a rancher cornered one while hunting and wisely decided to shoot film instead of lead. The state then decided to look for Jaguars. They have found several using remotely triggered cameras.

From what I understand they have dozens of cameras out at one time, so whatever system they use is most likely pretty cheap. It is also durable. Contacting them could be valuable.

 

[balint]

dnmilikan,

it is a good idea to incorporate the transmitter and the receiver into the same box and use some refelctor. This would also allow us to have use plug/sensor. We will evaluate this idea. Thanks. This is a really good idea.

We are trying to keep the system as simple as possible, so the whole system would be wired. Wires between the sensors (TX, RX) and the cameras as well. Radio control would be definitely more comfortable but also more expensive and less reliable.

For my own purposes, wires are no problem. However I want to keep system latency as low as possible and radio interfaces would introduce an additional delay (as it needs coding-decoding plus loads of communications problems has to be addressed). I think, that at least in the beginning we will stick to the wires.

 

[Donald Miller]

The suggestion about an IR beam seems good at the outset, however I see a problem with fluctuations during daylight and night shots, especially if this were installed for a period of days. I remember reading about one of the Natl Geo photogs that was in a tree blind for a number of days in South America.

In addition to the thoughts of using a reflector as a reference point for the laser, if that were not feasible...in your development, the other thing that would work is to set the laser up as a remote battery powered unit unconnected to your sensor and your logic unit. By doing it that way there would only be the effect of a switch closing or opening (depending on your circuitry) between your sensor and logic unit as the laser beam is interrupted. I have seen small levels that are laser and are battery powered. These are relatively inexpensive insofar as these devices are concerned. They are normally available through the building craft magazines among other sources, should you decide that is an option.

At any rate, good luck.

 

[balint]

In addition what dnmilikan said about IR, I have to say thtat IR isn't convergent which makes it useless when the distance between TX and RX units is large.

On the other hand there is one problem with a battery powered stand alone TX unit. We are using visible 650nm class II laser (for obvious reasons like alignement) therefore we decided to switch off the laser whenever the beam is broken.

The user doesn't want to see red spots (caused by the laser transmitter) on his/her photos. In order to do this we decide to power everything from the main controller unit.

Yes, there are going to be lot's of cables, but the good news is that the same cable will be used all over the system.

 

[Donald Miller]

I understand the reasoning behind turning off the laser. The question that still comes to mind for me is what about "hiding" the cables? This seems to something that I would find problematic as a potential purchaser or user? Other then having white cables for photographing a polar bear on ice and snow, how will the cables be hidden? Then if white is used, this color will be very noticable and needing to be addressed in a woodland scene. What about stringing cables through water for photographing gators in the swamp? Will the cables and componants be water proof and not subject to shorting or open circuits? Have you checked into the actual cost of RC componants? I would think that the cost would not be prohibitively expensive, it would afford much more flexibility to an end user other then yourself. How about the technology that already exists with the Mamiya flash triggers? Please understand, I am not intending to find fault with your considerations. My intentions are to raise questions that will challenge the already existant creative potential that you have and to use that potential to the greatest benefit. Good luck. Sounds like a very exciting time for you.

Regards,

Donald Miller

 

[SteveGangi]

There already is such a gizmo, called a Dahle beam (not sure of the spelling). The way it works is, the animal moves between the transmitter and receiver, and the camera strobe is triggered.