I find that when I focus the camera on a target with a lot of detail such as a screen displaying a lens test chart, the live view in the IDE will return a black white pattern of squares.
holding my hand in front of it (or defocusing the lens) immediately brings back a usable image:
I think this only happens when the sensor is in JPEG mode at a high quality setting (>80) with sensor.set_quality, and I am wondering whether it is related to the fact that images with high JPEG quality are often incompletely saved such as in this example (the image was even in black-and-white, even though the pixformat was set to JPEG, using 4.1.1 firmware):
or this example with an image saved while the board was not connected to the IDE (with a previous firmware, maybe 3.9 or 4.0, notice the gray bar at the bottom):
So: given that the advice in the documentation for people using the high resolution modes is to use the JPEG pixel format, and given that a high JPEG quality is desirable, how do we get to see and save a stable image feed from the sensor at these high-res, high-quality JPEG settings?