Highlighted rows differ between the two models.
| Specification | Canon EF 300mm f/2.8 L IS II USM | Canon EF 600mm f/4 L IS USM |
|---|---|---|
| Mount | ||
| Mount | canon-ef | canon-ef |
| Optics | ||
| Focal (difference) | 300 mm | 600 mm |
| Aperture (difference) | f/2.8 | f/4.0 |
| Prime | Yes | Yes |
| Stabilization | Yes | Yes |
Pick Model A if you need the brighter f/2.8 aperture for low-light performance or shallower depth of field, or if the 300mm focal length better suits your framing needs. Choose Model B if the extra reach of 600mm is essential for distant subjects, and you can work with the slightly slower f/4 aperture. Budget is nearly identical, so the decision hinges solely on focal length and aperture requirements.