Shutter Speed Below Frame Rate at DVinfo.net

Lloyd Coleman · February 8th, 2007, 04:09 PM

The A1 (and probably other camcorders) allow you to set the shutter speed slower than the frame rate. How is this possible? For example, if I open the shutter for 1/6 of a second, 5 frames of video are captured while the shutter is open, therefore, each frame was not exposed for 1/6 of a second. It seems like the frame rate is as slow as the shutter could effectively operate.

Thanks for helping me understand this.

Bogdan Tyburczy · February 8th, 2007, 05:02 PM

It's all electronic process. In your example, camera allows to accumulate images on sensors for 1/6 second just like photo cameras do, then closes electronic shutter and generates 5 identical frames based on accumulated image. The process is repeated 6 times per second resulting with 6 images sent out in stream of 30 frames.

Chris Hurd · February 8th, 2007, 05:22 PM

Right, those slow shutter speeds are electronically created. There's nothing "mechanical" about them.

February 8th, 2007, 04:09 PM	#1
Lloyd Coleman Major Player Join Date: Oct 2003 Location: Salt Lake City, UT Posts: 256	Shutter Speed Below Frame Rate The A1 (and probably other camcorders) allow you to set the shutter speed slower than the frame rate. How is this possible? For example, if I open the shutter for 1/6 of a second, 5 frames of video are captured while the shutter is open, therefore, each frame was not exposed for 1/6 of a second. It seems like the frame rate is as slow as the shutter could effectively operate. Thanks for helping me understand this.

February 8th, 2007, 05:22 PM	#3
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	Right, those slow shutter speeds are electronically created. There's nothing "mechanical" about them. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

February 8th, 2007, 05:02 PM	#2
Bogdan Tyburczy Regular Crew Join Date: Oct 2006 Location: Brooklyn Posts: 161	It's all electronic process. In your example, camera allows to accumulate images on sensors for 1/6 second just like photo cameras do, then closes electronic shutter and generates 5 identical frames based on accumulated image. The process is repeated 6 times per second resulting with 6 images sent out in stream of 30 frames.