{"id":592,"date":"2011-09-27T08:53:29","date_gmt":"2011-09-27T16:53:29","guid":{"rendered":"http:\/\/coldstreams.com\/video\/?p=592"},"modified":"2011-09-27T08:53:29","modified_gmt":"2011-09-27T16:53:29","slug":"dslrs-and-rolling-shutter","status":"publish","type":"post","link":"https:\/\/coldstreams.com\/3d\/2011\/09\/27\/dslrs-and-rolling-shutter\/","title":{"rendered":"DSLRs and rolling shutter"},"content":{"rendered":"

“Rolling shutter<\/a>” is a video image distortion that commonly appears when using modern CMOS-based<\/a> DSLRs<\/a> – and also CMOS-based consumer camcorders. It manifests as a wobbly or skewed image. In the simple case, a fast pan left or right causes vertical lines to become slanted and bent. In a more typical case, portions of the image can appear wobbly if the camera – or the subject – are moving left or right.<\/p>\n

I’ve elevated the following to its own blog post; it first appeared within the following post about the new Canon SX40IS. I also wrote about rolling shutter before<\/a>.<\/p>\n

I\u2019ve been discovering some issues with rolling shutter on my Lumix<\/a> GH-2<\/a> when using long telephoto settings that are, for me, more problematic than fast pans. Specifically, if I use the 45-200mm zoom at the 200mm setting (think 400mm full frame equivalent lens), and then switch into the ETC extended digital teleconverter mode where it isolates just 1920\u00d71080 pixels (multiply by 2.6 times) giving a 1040mm (full frame) effective lens, the very slightest motion produces skew and wobble in the image.<\/p>\n

Last week I shot a scene using this feature \u2013 since a 1040mm equivalent lens is compressing a huge amount of atmosphere, the thermal refraction occurring in the image made the image wobble. And sure enough, that resulted in rolling shutter issues even though the camera was locked down securely on a tripod!<\/p>\n

Some day \u2026 an electronic global shutter will be added to CMOS sensors, I suppose. Until then, for long range video shooting, I prefer CCD imagers.<\/p><\/blockquote>\n

Is rolling shutter a problem? Some claim its not if you merely plan your images in advance. For those who can plan their images, this strategy may work fine.<\/p>\n

But I shoot a lot of live events that I do not control and or which there can be only minimal planning. I am finding that DSLRs are great for shooting video:<\/p>\n