Highlighted rows differ between the two models.
| Specification | Canon EF 100-300mm f/4.5-5.6 USM | Canon EF 70-210mm f/4 |
|---|---|---|
| Mount | ||
| Mount | canon-ef | canon-ef |
| Optics | ||
| Focal (difference) | 100-300 mm | 70-210 mm |
| Aperture (difference) | f/4.5-5.6 | f/4.0 |
| Prime | No | No |
| Stabilization | No | No |
Pick Model A if you need the extra reach (300 mm vs. 210 mm) and can accept the slightly slower aperture at the long end. Model B stays the better choice if budget is tight, a constant f/4 across the zoom range is more important, or the 70 mm wide end suits your framing needs.