This is pretty slick - I am going to try this over the next week or so and see how it works. THe forum write up looks pretty promising. The PDF documentation that is downloadable from the forum starts like this:
If you are tempted to answer “yes”, read on.
Here is the link to the ML Forum post:
In essence, ML permits you to set up your exposure so that, for a single click of the shutter release, half of the sensor data is acquired at ISO 1 and the other half acquired at ISO 2. So, for example, you could use ISO 100 and 800 and shoot a scene that will read off half of the sensor at ISO 100 and the other half at ISO 800 (alternate sensor rows - actually alternating every two sensor rows to get the complete RGGB sensel block). This means you are capturing a single image, including motion blur and moving objects with two exposures simultaneously. The tradeoff is half vertical resolution, as the above quote indicates, as well as aliasing in the highlights and shadows, where the skipping of lines is more evident.
I look forward to trying this.
The workflow required to convert your raw image to something useable is provided by additional applications or adaptation of existing open applications (like EXIFTool and dcraw).
Previous extension of DR with ML (especially for video) used alternating ISOs but per frame - that is, capture frame 1 at ISO 1 and frame 2 at ISO 2 and combine these two frames into a single frame and repeat. This leads to some complex frame blending issues that have been pursued and solved in novel ways, thanks to John Hable (GingerHDR). A1ex's dual ISO readout is an equally clever approach that promises even better coping with motion with extended DR.
A1ex never ceases to amaze.