MichaelMeissner
Senior Member+
Now, I have several projects in various states of assembly/disassembly, and I really don't need another one, but in perusing the digital camera groups, I came up with another project.
For digital photography, I use Olympus and Panasonic micro 4/3rds cameras. The micro 4/3rds cameras, while popular, don't have the market penetration that Nikon, Canon, and Sony have, so you don't get as many third party developers adding specific products for the market.
In particular, Olympus/Panasonic offer wireless flash systems that rely on light pulses from the master controller (typically the built-in or clip-on flash on the camera) to send control signals to the remote flashes (flashes can be in up to 4 groups, and from the camera, you can control each of the groups to adjust amount of light, etc.). It is a TTL (through the lens) system, where the camera first tells the flashes to do a pre-flash, it records the light, and then calculates the amount/duration of the flash for real when the picture is taken. There is no feedback from the flashes back to the camera, the communication is all one way.
While the system works, there are some drawbacks: 1) it doesn't work well outdoors since the sun overpowers the light from the camera, and the flashes can't determine that a flash pulse occurred; 2) the system only works if the flashes can see the pulses from the camera, so you need line of sight; 3) there are distance thresholds as well.
There was a third party vendor (aoktec.com) that offered a system where you had a transmitter clip on to the camera's flash, and it would convert the pulses to radio waves, and each of the receivers would position a LED over the flash sensor, and convert the radio waves back to visible light. However, the company has abruptly removed the products from being sold without an explanation. It could be the remote flashes just didn't sell well, or perhaps they didn't have the necessary permits for commercial operation, or perhaps they got threatened for patent infringement.
In any case, it seems like a simple project, put one Teensy LC (or other microprocessor) with a light sensor over the flash (and make a hood, so the sensor only sees the flash), and have it communicate to the remote microprocessors over radio waves, and have them convert the pulses back into visible light. You only need a byte of data (plus address bytes for packetized radio), but it needs to be fairly low latency to send the bytes in real time. And the radio system needs to be 1 to many.
I tend to think wifi is too much overhead for this system. Bluetooth classic is only 1-to-1 communication, and BLE tends to be expensive. It would go several meters, but it doesn't need extreme distances. It does need to be non-line of sight, but it doesn't need to go through thick walls. nRF24L01+ might be a possibility -- I bought several of these some time ago, but I haven't used them. I see Adafruit having RFM96W and LORA radios for their feather systems, and these might work as well if they can do the 1-to-many transmission.
In terms of radio regulations, etc. I live in the USA. I plan to do this as a personal project. While I would put the source online, I don't see making a product of it.
Any thoughts on what radio system to use?
For digital photography, I use Olympus and Panasonic micro 4/3rds cameras. The micro 4/3rds cameras, while popular, don't have the market penetration that Nikon, Canon, and Sony have, so you don't get as many third party developers adding specific products for the market.
In particular, Olympus/Panasonic offer wireless flash systems that rely on light pulses from the master controller (typically the built-in or clip-on flash on the camera) to send control signals to the remote flashes (flashes can be in up to 4 groups, and from the camera, you can control each of the groups to adjust amount of light, etc.). It is a TTL (through the lens) system, where the camera first tells the flashes to do a pre-flash, it records the light, and then calculates the amount/duration of the flash for real when the picture is taken. There is no feedback from the flashes back to the camera, the communication is all one way.
While the system works, there are some drawbacks: 1) it doesn't work well outdoors since the sun overpowers the light from the camera, and the flashes can't determine that a flash pulse occurred; 2) the system only works if the flashes can see the pulses from the camera, so you need line of sight; 3) there are distance thresholds as well.
There was a third party vendor (aoktec.com) that offered a system where you had a transmitter clip on to the camera's flash, and it would convert the pulses to radio waves, and each of the receivers would position a LED over the flash sensor, and convert the radio waves back to visible light. However, the company has abruptly removed the products from being sold without an explanation. It could be the remote flashes just didn't sell well, or perhaps they didn't have the necessary permits for commercial operation, or perhaps they got threatened for patent infringement.
In any case, it seems like a simple project, put one Teensy LC (or other microprocessor) with a light sensor over the flash (and make a hood, so the sensor only sees the flash), and have it communicate to the remote microprocessors over radio waves, and have them convert the pulses back into visible light. You only need a byte of data (plus address bytes for packetized radio), but it needs to be fairly low latency to send the bytes in real time. And the radio system needs to be 1 to many.
I tend to think wifi is too much overhead for this system. Bluetooth classic is only 1-to-1 communication, and BLE tends to be expensive. It would go several meters, but it doesn't need extreme distances. It does need to be non-line of sight, but it doesn't need to go through thick walls. nRF24L01+ might be a possibility -- I bought several of these some time ago, but I haven't used them. I see Adafruit having RFM96W and LORA radios for their feather systems, and these might work as well if they can do the 1-to-many transmission.
In terms of radio regulations, etc. I live in the USA. I plan to do this as a personal project. While I would put the source online, I don't see making a product of it.
Any thoughts on what radio system to use?
Last edited: