Mirror lockup

Forums General Questions and Comments Mirror lockup

  • This topic has 2 replies, 2 voices, and was last updated 12 months ago by .
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    • #1911 Reply

      While awaiting delivery of my components I loaded the sketch and did some prototyping using a breadboard and LED’s on all the ports.
      It all went as expected except for the mirror lockup.
      With MLU on I see both mirror and shutter LED’s lighting up at the same time twice
      I expected to see the MLU LED to light up, then the shutter LED, then the flash LED, then the flash LED off followed by the other LED’s .
      Am I missing something.

    • #1921 Reply

      The mirror lockup trigger is in the makeDrops sketch at line 68.

      All it does is set the shutter and focus pins HIGH, wait for the pulse time and then set the pins LOW. The sketch then waits for the mirror lockup delay time.

      I use a Canon camera which requires both focus and shutter to be HIGH to trigger bulb mode so I use both together for all trigger events. If your camera has different requirements change the following to suit.

      cameraTriggerTime_Stop is cameraTriggerTime_Start + the trigger pulse time. The trigger pulse time is set to 50ms as default.

      // activate mirror lockup
      if (mirrorLockup && !aborted)
      digitalWrite( cam_TrigFocusPin, HIGH );
      digitalWrite( cam_TrigShutterPin, HIGH );
      delay( cameraTriggerTime_Stop – cameraTriggerTime_Start );
      digitalWrite( cam_TrigFocusPin, LOW );
      digitalWrite( cam_TrigShutterPin, LOW );

      done = false;
      long unsigned startTime = millis();
      while (startTime == millis()) // This makes sure we are starting at the beginning of a millisecond
      startTime = millis();

      while (!done)
      if (millis() – startTime >= mirrorLockupDelay ) { done = true; }


      • This reply was modified 5 years, 9 months ago by Martyn.
    • #1922 Reply

      Thanks Martyn
      You really are a great help
      I commented out the shutter high line in the mirror lockup sequence. It now behaves exactly as I expected
      Of course I have no intention of actually using mirror lockup. I do not believe it is useful in this type of photography.
      I shall be using the MLU pin to control an external lamp. I also intend to utilize another two or three pins for extra flashes and I have noted in another post how to do this.
      I look forward to your next release with individual flash delays.
      Keep up the good work

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