Unofficial DSLR upgrade gives better movie control
A firmware upgrade by a group of filmmakers has been released to alter and improve the performance of a number of DSLRs, including the EOS 5D Mark II. Magic Lantern makes a number of changes to the existing system within the DSLR, including modifications to how the audio is controlled.
An audio level indicator has been added, as well as headphone monitoring, to allow the user to control the amount of distortion the camera records. The camera also performs an amount of audio control itself using Automatic Gain control, or AGC. A number of filmmakers have found issues with the camera increasing gain in periods of silence and clamping down too harshly when the sound frequency increases. Magic Lantern remedies this by altering how the AGC operates, replacing the camera’s internal amps to allow the sound to be controlled by an external unit.
In terms of image quality there are a few exposure aids added to the firmware, including a live waveform that operates in a similar manner to a live histogram by giving a preview of the light levels on a graph.
The firmware can be upgraded via a Compact Flash card, although its worth bearing in mind this is an unofficial modification so may be susceptible to faults. Magic Lantern isn’t a permanent upgrade so can be easily removed if problems occur.
More information can be found at the Magic Lantern Wiki