New answers tagged noise
When using CCD and CMOS sensors, the distribution of the DC component of the sensor noise rarely changes with time (unless you plan on using your camera in extreme temperatures). This allows for effective factory measurement and calibration which allows them to measure and remove the dark frame automatically. So I don't think there is much use in trying to ...
What is probably going on has little to do with the camera sensor, per se. When the signal from the sensor is processed there is noise reduction applied. It seems that in the case of your webcam, the processor recognizes a "noise only" black frame and goes ahead and eliminates all of the signal to get rid of the noise.
In digital photography, ISO speed rating does not characterize sensor sensitivity. ISO speed setting on a digital camera is controlling the amount of amplification / multiplication of the signal from the sensor after the data is already captured. ISO speed does not control the sensitivity of the sensor, and is more like a "push" processing of a film, thus ...
There are basically two ways to approach this. In both cases what you are doing is increasing the amount of total light that enters the camera so that the random nature of photon shot noise is minimized by the increased amount of total data (photons striking pixel wells). Long exposure images shot at lower ISO when combined with dark frame subtraction. ...
I'd say highly detailed because a) noise in low detail areas stands out, and b) where there's detail, noise can actually make an image appear sharper. This only applies if the size of the detail is larger enough compared to the size of the noise pattern.
If you're shooting in low light, the noise is mostly caused by the randomness of the number of photons hitting each sensor sight. So in one sense what you're shooting doesn't matter. But... you can reduce the noise a good deal if you take multiple exposures of the same scene and then stack and average them in post-processing. So my answer is a static subject ...
Top 50 recent answers are included