Timeline for Why do DSLRs in movie mode have a rolling shutter instead of a global shutter?
Current License: CC BY-SA 2.5
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 15, 2011 at 22:48 | comment | added | Nick Bedford | Makes it sound tiring, running around in the rain emptying buckets. | |
| Feb 24, 2011 at 20:57 | comment | added | Jukka Suomela | @Jerry: Yeah. Tried to keep it simple (and 600 characters long). | |
| Feb 24, 2011 at 20:45 | comment | added | Jerry Coffin | @Jukka Suomela: Nice analogy, except for one minor point: it can actually empty an entire "row of buckets" at once, not just one. | |
| Feb 24, 2011 at 20:43 | comment | added | Jukka Suomela | It might help a bit (or confuse) if you think that light = rain and a pixel = bucket. And in a CMOS sensor, the only way to check how much water you have in each bucket is to empty the bucket. You can only empty the buckets one by one, and it is raining all the time. The "movie mode" simply means that you are running around in the rain, emptying the buckets. The "photo mode" is different: first set up a cover on top of your field of buckets; then you go around and empty each bucket; then you remove the cover for a while and put it back ("exposure"); then you empty each bucket and measure them. | |
| Feb 24, 2011 at 18:35 | vote | accept | Andres | ||
| Feb 24, 2011 at 17:20 | comment | added | Jerry Coffin | Because there's isn't a command to "turn off" light sensitivity. There's just reading the data from a cell, which drains the charge in that cell. | |
| Feb 24, 2011 at 17:10 | comment | added | Andres | So, it's correct to say that in stills mode, the CMOS acts PARTIALLY as a global shutter (As all the light exposes the sensor as a whole, and then, when there isn't any more light hitting it, each line is read)? But why, if the camera uses an electronic shutter (which I guess commands the sensor when has to be light sensitive), still there is skew artifacts? I mean, if the sensor receives the light as a whole, then the electronic shutter hits, and then the lines are read, why there are rolling shutter artifacts? | |
| Feb 24, 2011 at 16:45 | history | answered | Jerry Coffin | CC BY-SA 2.5 |