Controlling the shutter speed of Pi cam

[Ginnychabada]

Hi, I have been trying to use Raspicam library in c++ without Opencv for a few days now. I have tried to set the shutter speed of the picam using the function 'setShutterspeed' . I have used the values ranging from 1 to 0.00001 .The picture taken by giving the value '1' as shutter speed is a complete black frame. And the picture with values from 0.99999 to 0.00001 are all same. Can somebody tell me why there is no difference between the other pictures and why the one with '1' is all blacked out. And rest all functions like setContrast , setBrightness etc are working fine.

I also have 2 doubts :
1.What is the units in which this function takes in input. (seconds or milliseconds)?
2.Will the shutter speed affect be of any visibility while clicking pictures of objects at rest?

[dgordon42]

1.What is the units in which this function takes in input. (seconds or milliseconds)?

I have never used the Raspicam C++ library, but the 'raspistill' command sets the shutter speed in MicroSeconds.

Code: Select all

raspistill --help

Hope this helps,
Dave.

[Ginnychabada]

Yes, it works now. Thanks

[anujgpatil]

Hi, I have been trying to use Raspicam library in c++ without Opencv for a few days now. I have tried to set the shutter speed of the picam using the function 'setShutterspeed' . I have used the values ranging from 1 to 0.00001 .The picture taken by giving the value '1' as shutter speed is a complete black frame. And the picture with values from 0.99999 to 0.00001 are all same. Can somebody tell me why there is no difference between the other pictures and why the one with '1' is all blacked out. And rest all functions like setContrast , setBrightness etc are working fine.

I also have 2 doubts :
1.What is the units in which this function takes in input. (seconds or milliseconds)?
2.Will the shutter speed affect be of any visibility while clicking pictures of objects at rest?

1. Answer to 1 is pretty clear -microseconds.
2. Here it must be understood that shutter speed is directly related to the amount of photons that hit the sensor while capturing an image.
So if the SS is ~10s of microseconds ,it'll probably be a very very dark image. So for low light photography,it SHOULD be wise to keep shutter speed in few hundred milliseconds(for stationary objects at rest) and few milliseconds for faster objects.

Hope that helps!
@anujgpatil