You asked
What is 50 100mm on canon aps c in full frame?
50-100mm on APS-C (Canon) gives the view of 80-160mm on full frame.
The same view on every common format:
- Medium format (44 x 33): 101-203mm
- Full frame: 80-160mm
- APS-C: 53-107mm
- APS-C (Canon) (yours): 50-100mm
- Micro Four Thirds: 40-80mm
- 1-inch: 30-59mm
- 1/1.3-inch: 22-44mm
- 1/1.7-inch: 17-35mm
- 1/2.3-inch: 14-29mm
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.