7 bias, dark & flat frames
bias偏向、偏置,这个具体要看上下文
dark frame暗底,采用相同的曝光时间拍摄一幅全黑的图像,一般就是盖上镜头盖,体现了系统的噪点。拿现有的照片去减dark frame就可以得到去除噪点的照片。
flat frame平场,一般是拍摄一个照度完全均匀的区域,得到的图像可以反映镜头或系统的缺陷(例如边缘更暗,失光)
well depth:
a good rule of thumb is to limit your pixel saturation to 50% of your well depth.
Your software will be able to tell you the saturation of a pixel and your CCD documentation will tell you the well depth of your pixels.
bias:
A bias frame is basically an image taken with the shutter disabled. The image will consist only of read-out noise and noise caused by interference of the computer. What a bias frame does is set the zero point of the CCD output and the pixel scales to the same value. This makes the final image more accurate since the zero points are equal and no nonlinear pixel values exist. --bias到底是什么?电脑是如何影响的?还有读出噪音请一并解释一下。
[quote:b9e262cdf2="Norman"]well depth:
a good rule of thumb is to limit your pixel saturation to 50% of your well depth.
Your software will be able to tell you the saturation of a pixel and your CCD documentation will tell you the well depth of your pixels.
bias:
A bias frame is basically an image taken with the shutter disabled. The image will consist only of read-out noise and noise caused by interference of the computer. What a bias frame does is set the zero point of the CCD output and the pixel scales to the same value. This makes the final image more accurate since the zero points are equal and no nonlinear pixel values exist. --bias到底是什么?电脑是如何影响的?还有读出噪音请一并解释一下。