Gain settings

[mlysbakken]

The custom has become that we start threads about things we know much about, but I thought I'd make a new one for something I'm still not entirely sure about. The idea is that people can share their results and knowledge regarding different gain settings.

To kick it off:
In the menu of the f35 it's iindicated that a gain of 12dB equals an ISO of 2000, and that the dynamic range is still 800 %. Through my tests I've found that 12dB adds a surprisingly "low" amount of grain, but it's hard to say how many stops are gained. The dynamic range seems to remain intact.

Here are some stills:

0 dB


3 dB


6 dB


9 dB


12 dB



EDIT: Wow, dvxuser's compression really killed those pics...

 

[TheWakePlace.com]

Gain and more exposure in an image doesn't always mean more dynamic range. Sometime in something like a Log setting, its hard to see any data loss when you up the gain. From my own experience shooting at higher gain settings on the F35, you are taking yourself further away from a true black in the image (if there is one to be had) and the image will become a lot more contrasty as a result to get the desired look.

The F35 gain does work surprisingly well when there is a light source though, really allowing you to maintain a natural look. I feel your first image actually has a more realistic and nicer exposure and tone to it, and the 12db image looks pushed (obviously as thats what you're showing here), but the gain should be used with caution regardless gf noise. Everytime you change that gain level, you are effecting every channel that the camera is picking up. Depending on your workflow, you can sometimes get away with it having beautiful results....

 

[Hunterqual]

What settings did you use for the test? Assuming slog, but what flavor of codec/bitrate? Noise suppression off/on?

... I realize this was awhile ago now! There are so many settings options and codec variables that it would help to be specific about these things.

 

[JMtheDP]

Bizarrely, I only ever use high gain when I have plenty of light to spare. The bottom couple of stops of the image suffer the biggest noise increase. So, outdoors in daylight, overall noise is not objectionable (to some) at 12db. At night, with little light though, the whole picture becomes a mess.

 

[mlysbakken]

Slog in DNxHD, if I remember correctly. No noise suppression, but James is right about the results being entirely different when you've got a darker base image. I'm not going to touch the gain very often on this camera.

 

[Hunterqual]

Cool, thanks. I've often wondered why Sony added those gain settings (and modified them in the firmware update), because they do not seem to be usable. I have trouble imagining the productions at the level that this camera was intended putting themselves in a situation where they would be forced to rate the camera above 800. This doesn't seem to be the camera to film a scene by candlelight, but maybe I'm missing something. Noise suppression does seem to help.