Introduction

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In 2006, my friend Dave showed me some Polaroids that a former co-worker of his was making in California with his 4×5 Speed Graphic. We were thinking about how cool that must be, and I remembered that my dad had one. He had it on display in his studio for a few years, and never used it. A fellow photographer had retired and dad bought some of his gear, including this camera.

So, I asked my dad if he had a Polaroid back for the camera, which he didn???t. But he offered me the camera and gave it to me around thanksgiving 2006. I???ve been making large format pictures with it ever since. I???ll be posting pictures and stories as much as I can.

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Camera Shutter Tester

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I make pictures with this 1951 press camera (a 4×5 Graflex Speed Graphic) and I wanted a way to check the accuracy of the leaf shutter in the lens as well as the rear curtain shutter.

The only ways I had found to do this are to buy an expensive testing machine, or to pay someone to use that machine they’ve bought, or the “sound card shutter tester” along with Audacity, which seems pretty kludgy and takes too much human effort.

But with Arduino, I knew I could make something on my own.

So I got an infrared emitter and sensor pair from SparkFun and I wired them up like this:

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I wrote this simple Arduino sketch:

#define receiverPin 12 // input from the ir receiver.unsigned long duration; // time shutter is openvoid setup(){  pinMode(receiverPin, INPUT);  Serial.begin(9600);}void loop(){  //digitalWrite(ledPin, !digitalRead(receiverPin)) ;  duration = pulseIn(receiverPin, LOW);  if(duration != 0 )  {    Serial.println(duration);  }}

And here is is set up to use:

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I put the emitter on one side of the lens, the sensor on the other, and trip the shutter. The serial console shows me the open duration in microseconds, which I compare to what it should be.

Now I can see how accurate the shutter is, and I can adjust the exposure if necessary. (Or even send the equipment out for repair or adjustment.)