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Spotting

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Critters:
What causes the mottled spotting in lower light? I've done multiple black calibrations but that doesn't seem to improve things.

Here's a gif showing it against a white door:

tesla500:
Hey Critters,

That's a calibration issue, we have contacted Luxima, the image sensor manufacturer, and they suggested adding 3-point calibration to fix the issue. We're currently using 2-point calibration. This is high priority on the list of things to fix.

Basically, due to variations in the semiconductor production process, some pixels have a response that is non-linear, with slightly less response when dark compared to in brighter light. As a result, they need more gain applied, but only in dark areas. The 3-point calibration will do this.

To minimize this for now, try to avoid using analog gain as the problem is worse at higher gain, and expose your images as bright as possible to bring up the pixel levels. Applying gain afterwards will also make the spots more noticeable.

David

Critters:
Great to hear it's a software fix, keep it up! :)

Camoit:
Please keep us informed on this fix.
This would be an issue my editor would see and ask me about it. Now that I know about it I have seen them in other youtube videos.

JamesB:
After some careful testing today it is clear the camera will show much fewer spots when over exposed or near over exposure. As David said above the 3 point calibration should fix it.

Image quality is the most important aspect of any camera and fixing this is top on the list, rest assured this is getting worked on. 

Some cameras will show more than others and there is an irregular pattern from each sensor.   I worked on After Effects to try to correct it and while cloning is a kind of fix, it introduced several hours of trial and error to get the shot to a place where I would be able to say it is acceptable.  It would take about 4-5 hrs of cloning to get a 30-second static shot clean which is what I did (Do not recommend it!).  The other fix I found where it was much faster is the "dust and scratches" filter in After Effects.  Only problem is resolution is decreased severely by applying it.  After it, however, it mostly cures the shot but makes it look posterized and water color like even at it's lowest setting.

After the dark dot issue is fixed and based on the incredible footage I was able to gather today, I would say the camera + sensor are extremely good in detail, color and dynamic range.

Some sample frames from today!

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