When using silent mode (simple, DNG) and the intervalometer I get a certain amount of black frames. For example, in 300 frames I got 14 fully black frames. The reason for the appearance of black frames could not be established. Black images are formed in an arbitrary order.
I was also able to find a workaround. 1. Run intervalometer in simple. 2. Waiting for 1 frame. 3. Change simple to full-res and turn into LiveView mode. 4. Waiting for 1 frame. In this case, we get a completely white frame and RAW ERROR. 5. Change full-res to simple. 6. The rest of the session goes by without black frames.
Canon 550d, firmware 1.0.9, magiclantern-Nightly.2018Feb04.550D109