Joaquín de prada in Opensx70 1 minute

Aperture and shutter speed conumdrum

This is my video. You judge. When I set a delay of 66mns on the arduino, is aproximately the minimum speed for which the SX70 goes full open to f/8.

So my question is… when do I start to meassure the time? What is the delay? Do I have to use EV to the faster speeds, given that the camera is not reaching f/8 but it would be nice to have a “fast” “speed” to use ASA600 film on daylight…

You can digg on an old patent and solve, in a way the aperture question, but, in reality only experimentation will tell. I have “cleaned” the graphic to try to enhance quality:

Fire image

So there has to be a delay? How much?