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Flash + MD = seizures... I mean communication

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Flash + MD = seizures... I mean communication
« on: 25 / November / 2009, 11:12:35 »
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I was just thinking if it would be possible to use the timeing of the flash and then something like the lighting detection script to send information bethen the cameras?  Any one trid this before? 

I got the idea from making a camera to attach to the hotshot so I can take pictures of what I'm shooting.  :lol



It's a normal visible light camera to attach to an IR modded SX10 is :D

Re: Flash + MD = seizures... I mean communication
« Reply #1 on: 26 / November / 2009, 03:52:44 »
The flash recharge is too slow to send meaningful messages.

8 flashes = 1 byte = 1 character of text

I'm guessing you could synchronize cameras this way, without a wire.

Re: Flash + MD = seizures... I mean communication
« Reply #2 on: 27 / November / 2009, 07:20:56 »
8 flashes = 1 byte = 1 character of text
???
That's the dumbist thing I'm read on the internet in a long time. :-)

Quote
D*mn it, Etilord. I'm a linguist not a mind reader!

If your channel only has 2 states you can't send only inform.

To send 1 bit you need the answer to an A or B question.
 
So we'll start with the flash off then the flash turns on then the flash turns off and we are back to the start.

"scene lit by flash" then
"scene not lit by flash" then
"scene lit by flash" then
"scene not lit by flash" then
"scene lit by flash" then
"scene not lit by flash" then
"scene lit by flash" then
"scene not lit by flash"

Notice that their is no 'or' in there?

You need AT LEST 3 states to send 1 bit of information.

Lucky that Canon's digital cameras have a clock to do this 0 bit communication for us with using the flash. :P


My proposle was to have all the cameras charge their flashs then the Bus master camera would flash. and all the camera's would start counting ticks on the clock. and the number of counts  between the last camera and the next would be encode the data.You would have to pre arrange the order of the camera's before hand.

so for a 3 camera example.  sending 8 bits each.
Lable 1:
All the camera's charge their flashs.
camera 0 flash and all the cameras sync their clocks.
Then the clock ticks once.
Then camera 1 flashes and the other cameras know that it's messages is 0 (00000000). GOTO Lable 2
OR
Camera 1 doesn't flash.
Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 1 (00000001). GOTO Lable 2
OR
Camera 1 doesn't flash.
Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 2 (00000010). GOTO Lable 2
OR
Camera 1 doesn't flash.
Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 3 (00000011). GOTO Lable 2
OR
Camera 1 doesn't flash.

...

Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 254 (11111110). GOTO Lable 2
OR
Camera 1 doesn't flash.
Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 255 (11111111) and the camera's sync their clocks. GOTO Lable 2
OR
Camera 1 doesn't flash. The the clock tick once more and the cameras assume Camera 1 has mal fuctioned.

Lable 2

Then the clock ticks once.
Then camera 2 flashes and the other cameras know that it's messages is 0 (00000000). GOTO Lable 3
OR
Camera 2 doesn't flash.
Then the clock ticks once more.
Then camera 2 flashes and the other cameras know that it's messages is 1 (00000001). GOTO Lable 3
OR
Camera 2 doesn't flash.
Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 2 (00000010). GOTO Lable 3
OR
Camera 2 doesn't flash.
Then the clock ticks once more.
Then camera 1 flashes and the other cameras know that it's messages is 3 (00000011). GOTO Lable 3
OR
Camera 2 doesn't flash.

...

Then the clock ticks once more.
Then camera 2 flashes and the other cameras know that it's messages is 254 (11111110). GOTO Lable 3
OR
Camera 2 doesn't flash.
Then the clock ticks once more.
Then camera 2 flashes and the other cameras know that it's messages is 255 (11111111) and the camera's sync their clocks. GOTO Lable 3
OR
Camera 2 doesn't flash. The the clock tick once more and the cameras assume Camera 2 has mal fuctioned.

Lable 3:

The camera's dicide who is going to be camera 0, 1, and 3. GOTO lable 1

Re: Flash + MD = seizures... I mean communication
« Reply #3 on: 28 / November / 2009, 13:56:29 »
Fake quotes, DrAlt? Not very nice. Well, I'm not even a linguist, so there's that.

And you knew what I meant, so it couldn't have been that stupid.

correction:
8 flashes (or lack of flash at the proper time) = 1 byte = 1 character of text

It doesn't look like you need any help though.


 

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