A couple of weeks ago I photographed the dashboard of a customer's luxury car (Daimler DS 420), but I'm not really satisfied with the depth of field of the photo, especially where the array of switches and gauges left of the steering wheel is:
Link to full-sized image: Daimler DS 420 dashboard
Parameters: f/8, 1/15", 28 mm, ISO 400. Canon EOS 70D + Canon EF 24–105 mm f/4 L IS
Illumination was quite good despite the fact that the car had a solid roof.
What's wrong here? Is there a method to make the field deeper without raising exposure time too much?