The elusive Indextron

[old_tv_nut]

Originally Posted by etype2

We touch and hold the LCD screen in the center of the video image and the camera reads the light of that point and locks the focus and exposure. It gives the best results. By doing this it darkens the surroundings.

This is a good procedure for getting an exposure that is correct for the image, no matter how bright or dim. Since it should give correct exposure of the picture for all cases (by adjusting shutter duration), you should be able to do a quick experiment by setting the Indextron for a dim picture and see if this causes the iPad to expand the shutter time.