EF Mount Compatibility – Please Read

PLEASE NOTE: Several Blazar lenses fitted with the official Blazar EF mount have a large rear protrusion that can prevent proper mounting on certain EF cameras and adapters. This applies to: Remus 33mm, Cato 40mm, and Mantis 25/35/50/75/100mm.

When EF Compatibility Is Unlikely (Incompatible Example)

• Older DSLRs that use a physical mirror and/or mechanical shutter assemblies.
• Speed boosters or EF adapters that contain optical elements, drop-in filters, or similar modules.
• Electronic EF adapters with internal contacts, boards, or housings that extend into the mount.
• Cameras/adapters with any parts that protrude deep inside the EF throat. If components extend past the inner mount boundary (see “Incompatible Example”), Blazar EF lenses may not seat or lock.

When EF Compatibility Is More Likely (More Compatible Example)

• Passive (non-electronic) EF adapters with a clear, open throat.
• Cameras/adapters that have no glass elements, drop-in filter modules, or internal parts sticking into the mount (see “More Compatible Example”).

How to Self-Check Before You Buy

1. Review the protrusion specs: Each Blazar lens has a technical diagram listing its rear protrusion for PL and EF mounts.
2. Compare against your camera/adapter: If your body/adapter’s maximum supported protrusion is greater than the lens protrusion, mounting should be possible.
3. Inspect the mount cavity: Look for electronics, glass, or mechanical parts extending past the inner mount circle—these are common points of interference.

Need the Drawings?

You’ll find technical diagrams for all Blazar lenses—showing rear protrusion measurements for both PL and EF—below on this page. Use these to confirm fit with your specific EF camera or adapter.

Questions?

If you’re unsure about your setup, contact us with your camera model and (if applicable) the exact adapter brand/model. We’re happy to help verify EF compatibility before you order.