title: How to addd user value to CMTimeMakeWithSecondValue
body: <p>Stop motion app</p>
  
  <p>Trying to get frame duration (/.5)set by users value received from a stepper:  <code>self.stepperValue;</code></p>
  
  <p>Original settings hard coded value of five frames a second</p>
  
  <pre><code>// 5 fps - taking 5 pictures will equal 1 second of video
  frameDuration = CMTimeMakeWithSeconds(1./5., 90000);
  </code></pre>
  
  <p>Now trying with frames per second determined by stepper value, What I've tried so far (stepperValue is being read correctly)</p>
  
  <pre><code> int x = self.stepperValue;
   frameDuration = CMTimeMakeWithSeconds(1./x, 90000);
  </code></pre>
  
  <p>This results on nothing being captured</p>
  
  <p>second attempt</p>
  
  <pre><code> float a = ([_stepperValue.text floatValue]);
  
  
  // 5 fps - taking 5 pictures will equal 1 second of video
  frameDuration = CMTimeMakeWithSeconds(1./a, 90000);
  </code></pre>
  
  <p>This results in a standard 5 frames per second value no matter value is entered form the stepper</p>