TeriTerryTarry
Well-Known Member
- Joined
- Dec 4, 2015
- Messages
- 661
- Reaction score
- 254
- Country
- United States
- Dash Cam
- Several action cams
The SJ4000 Wi-Fi has menu settings for ISO and Exposure but what do these really mean? I know that ISO has to do with sensitivity to light - the higher the ISO the greater the sensitivity. But when you change the setting, what's happening inside the camera to make this change come about? The sensor is not something that is programmable, i.e., it always does the same thing the same way, correct? Does changing the ISO setting have something to do with the programming of the image processor? On the SJ4000 the settings are 100, 200, 400 and Auto. Is 200 twice as sensitive as 100, and 400 four times as sensitive? Are these only relative terms specific to this camera or are these actual industry standard numbers comparable across all digital cameras? Does the setting apply to recording videos and shooting photos?
When I tested exposure with my camera I found that they fell into three groups with all the photos within a group having the same exposure despite the camera having multiple settings. This is no doubt a camera defect but if it had been operating properly one would see a gradual but noticeable change with each setting. But a change in what? It can't be an aperture setting because the camera has no moving parts. Is it the equivalent of shutter speed? But action cams don't have shutters. Therefore exposure must have something to do with the programming of the signal processor, but what? On the SJ4000 the range is -2.0 to +2.0 in 1/3 increments. And again does it apply to both videos and photos?
When I tested exposure with my camera I found that they fell into three groups with all the photos within a group having the same exposure despite the camera having multiple settings. This is no doubt a camera defect but if it had been operating properly one would see a gradual but noticeable change with each setting. But a change in what? It can't be an aperture setting because the camera has no moving parts. Is it the equivalent of shutter speed? But action cams don't have shutters. Therefore exposure must have something to do with the programming of the signal processor, but what? On the SJ4000 the range is -2.0 to +2.0 in 1/3 increments. And again does it apply to both videos and photos?