You asked
What is 15mm f8 on micro four thirds in full frame?
15mm on Micro Four Thirds gives the view of 30mm on full frame. For the same depth of field, f/8 there behaves like about f/16 on full frame. Exposure doesn't change: f/8 gives the same brightness on any sensor.
The same view on every common format:
- Medium format (44 x 33): 38mm at about f/20.3 for the same depth of field
- Full frame: 30mm at about f/16 for the same depth of field
- APS-C: 20mm at about f/10.7 for the same depth of field
- APS-C (Canon): 19mm at about f/10 for the same depth of field
- Micro Four Thirds (yours): 15mm at about f/8 for the same depth of field
- 1-inch: 11mm at about f/5.9 for the same depth of field
- 1/1.3-inch: 8.3mm at about f/4.4 for the same depth of field
- 1/1.7-inch: 6.5mm at about f/3.5 for the same depth of field
- 1/2.3-inch: 5.4mm at about f/2.9 for the same depth of field
Crop factors are by the sensor diagonal, rounded as they're usually quoted; a format with a different shape (4:3 against 3:2) frames a little differently across the width. More in the focal length converter.
Computed from the sensor sizes, not written by a model.