5D Mark II ISO Noise Test For Raw Files.
I've seen several tests like this for video mode, but never one for still images. Similar to video mode, the camera performs best at ISO settings which are -1/3 stop the native ISOs (eg 160, 320, 640, 1250) and performs worst at +1/3 stop the native ISOs (eg 125, 250, 500, 1000) . In some cases, significantly higher ISOs are found to be much cleaner than lower ones, such as ISO 640 being cleaner than ISO 125. The non-linearity seems to vanish at levels above ISO 1600 with each subsequently higher setting bringing more noise than the previous. The test was performed using 5-second exposures at each level, with the lens cap on and sealed with tape. The eyepiece was also sealed. Camera noise reduction was disabled. The test was performed three times to bring the camera up to stable operating temperature. Images were processed in Lightroom with exposure set to +3.00, blacks to 0, noise reduction and sharpening off, and white balance set to 5500K. Noise was additionally enhanced in Photoshop using levels. Merely a qualitative test, but it does reveal good information for those that want the absolute best performance from their 5D Mark II. Click image below or go to http://www.flickr.com/photos/30399777@N02/6015282702