Latest Magic Lantern hack brings super wide dynamic range to Canon cameras
posted Wednesday, July 17, 2013 at 12:57 PM EDT
The Canon specific firmware hack Magic Lantern has been on a roll lately. Earlier this year, it announced the ability to pull Raw video from some cameras, and now a programmer has added a function that could dramatically boost the dynamic range (to a reported 14-stop reach) for images and videos shot with the Canon 5D Mark III and the 7D.
This breakthrough comes from "A1ex," an admin over at Magic Lantern, who revealed a tool called "dual ISO". Rather than tying the entire sensor of the camera to a single ISO, this instead allows for it to alternate lines of pixels between two different ISOs. By setting these very far apart, at, say, ISO 100 and ISO 1600, you could rescue detail out of dark areas, maintain your highlights, and keep noise to a minimum.
But there are some downsides from the process. For one, moire is boosted substantially, the Raw files have to be run through a special process, and it does hit your resolution, too. This is also very early in the process, and there are some potential dangers. As A1ex says in the original post:
This code changes low-level sensor parameters. In the technical doc you can see how this method messes with the feedback loop for optical black, for example. Therefore, it's safe to assume it can fry the sensor or do other nasty things. My 5D3 is still alive after roughly one week of playing with this, but that's not a guarantee."
If you're interested in this process and how it works, there's a 20-page PDF that runs through all the technical information — but the takeaway is that this should give your camera a full 14 stops of dynamic range, keeping all the detail from both lights and darks.
Right now, it only works with video on the 5D Mark III, and will do photos on both that and the Canon 7D. But hopefully now that the feature has been released, people will be able to tweak, improve, and stabilize it.
Here's a brief example showing some of what it can do: