Author Topic: Flash strobing fire with long exposure  (Read 9316 times)

knoodrake

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Re: Flash strobing fire with long exposure
« Reply #25 on: November 10, 2016, 11:35:53 AM »
Quote
Do you have a way to trigger the flash manually without taking a picture?
Yes ! Or so I beleive.. In canon settings, I can set the DoF preview button for flash modeling ; So I press the button and the flash kinda-trigger (for modeling, so not a "usual" flash trigger, it's a something like 1s lasting high frequence sequence of low power trigger ) but anyway, more or less yes, I can fire the flash without taking a picture.
Not sure it helps, but I hope it does. I'll try logging while doing that.

knoodrake

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Re: Flash strobing fire with long exposure
« Reply #26 on: November 10, 2016, 05:22:49 PM »
Sorry to bother you again, but I can't figure how to trigger a key press ? ( is that even possible ? ) I tried
Code: [Select]
  module_send_keypress(MODULE_KEY_PRESS_DP);
in debug.c

But
  • I don't know if It's what I'm supposed to do
  • I'm not sure which key is MODULE_KEY_PRESS_DP ? ( I'm looking for DoF preview button, just next to the lens on 5d3 )

If not possible, I guess I can do something like:

Code: [Select]
static void run_test()
{
  msleep(2000);
  debug_intercept();
  /**
     some code that waits for the Keypress event for the key that I actually press with my finger after having called this run_test()

  **/
  msleep(2000);
  debug_intercept();
}

a1ex

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Re: Flash strobing fire with long exposure
« Reply #27 on: November 10, 2016, 06:15:40 PM »
Faking the DOF preview button is not very easy (see the sticky DOF feature). But waiting for a few seconds should do the trick - during this time, you just press the button. You may turn on the LED during this time, for example.

This sequence should run with display off, to minimize noise (lots of messages) from Canon GUI.

knoodrake

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Re: Flash strobing fire with long exposure
« Reply #28 on: November 10, 2016, 06:39:42 PM »
Thanks a1ex. Can't take the time right now to try to analyze (will try tomorow) but
that is the

of this code

Code: [Select]
static void run_test()
{
  msleep(2000);
  beep();
  debug_intercept();
  msleep(5000); // I pressed (and unpress) manually the DoF preview button durring those 5s
  debug_intercept();
  beep();
}

Quote
This sequence should run with display off, to minimize noise (lots of messages) from Canon GUI.
that's already the case when using don't click me right ? because my screen sure goes black.

--

EDIT: well, no time to analyze, but a quick look already tells that there is no mpu_send at all (although the flash did "model" fire)  :(

a1ex

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Re: Flash strobing fire with long exposure
« Reply #29 on: November 10, 2016, 08:23:15 PM »
Indeed; I guess the MPU decides to fire the flash when you press the button (based on the current settings), then it just informs the main CPU that DOF preview was pressed.