Canon enthusiasts have reason to celebrate as the highly anticipated EOS R6 Mark III is reportedly scheduled for announcement in late November 2025. Industry insiders point to two potential announcement dates: November 16 and November 26, though exact timing may vary by region. Canon EOS R6 Mark III is set to compete with the upcoming Sony a7 V.
Alongside the EOS R6 Mark III, Canon plans to introduce four new RF-mount lenses throughout the month. While all four may not launch simultaneously, three have been identified with strong confidence based on multiple sources and leaked survey data from Canon India.
Canon appears to be finalizing development of a highly anticipated RF 300-600mm f/4-5.6L IS USM lens, with sources suggesting an announcement could come before year’s end. This variable aperture telephoto zoom has been in development for over a year and represents a significant addition to Canon’s RF mount lineup.
Key Specifications and Features
The lens is expected to maintain f/4 aperture from 300-400mm, transitioning to f/5.6 from 400-600mm. While variable apertures typically concern some photographers, the anticipated size, weight, and cost advantages may make this compromise worthwhile for many users.
Pricing estimates place the lens between $6,499-$6,999 USD, though Canon enthusiasts hope it arrives under $6,000. Teleconverter compatibility remains unclear, but if the lens works with Canon’s 1.4x extender, it would provide an effective 840mm f/8 option for wildlife photography.
Market Positioning
Industry sources previously indicated this lens would “cannibalize” sales of the existing RF 100-500mm f/4.5-7.1L IS USM. The significant price gap between these models means many photographers might save longer to acquire the faster, longer-reaching option.
The RF 300-600mm would complement Canon’s recently announced RF 100-300mm f/2.8L IS USM, creating a comprehensive telephoto system without requiring teleconverters.
Development Timeline
Patent applications have surfaced showing supertelephoto RF designs with variable apertures, though none match this lens exactly. Canon rarely reveals exact optical patents before product announcements, making specific details limited.
With the lens reportedly undergoing final testing, photographers may not wait much longer. Canon appears poised for multiple announcements in coming months, beginning with the Cinema EOS C50 next week. For wildlife and sports photographers seeking extended reach with professional build quality, this lens could prove transformative.
