Firmware update for EF-M43 (Windows)

Firmware upgrade for Canon EF-Micro Four Thirds Smart Adapter^TM

RELEVANT PRODUCTS

This information is for the following models:

• Canon EF-BMCC T Speed Booster® (model : MB_SPEF-BMCC-BM1/MB_SPEF-BMCC-BT1)
• Canon EF-BMPCC T Speed Booster® 0.58x (model : MB_SPEF-BMPCC-BM1/MB_SPEF-BMPCC-BT1)
• Canon EF-BMPCC4K T Speed Booster® ULTRA 0.71x (model : MB_SPEF-m43-BT8/CINE: MB_SPEF-m43-BTA)
• Canon EF-BMPCC4K T Speed Booster® XL 0.64x (model : MB_SPEF-m43-BT9/CINE: MB_SPEF-m43-BTB)
• Canon EF-Micro Four Thirds Smart Adapter^TM (model : MB_EF-M43-BM1)
• Canon EF-Micro Four Thirds T Smart Adapter^TM (model : MB_EF-M43-BT2)
• Canon EF-Micro Four Thirds T Smart Adapter^TM II (model : MB_EF-M43-BT4)
• Canon EF-Micro Four Thirds T Smart Adapter^TM CINE (model : MB_EF-M43-BT3)
• Canon EF-Micro Four Thirds Speed Booster® (model : MB_SPEF-M43-BM1)
• Canon EF-Micro Four Thirds Speed Booster® "S" (model : MB_SPEF-M43-BM2)
• Canon EF-Micro Four Thirds T Speed Booster® ULTRA 0.71x  (model : MB_SPEF-M43-BT4/CINE: MB_SPEF-M43-BT5)
• Canon EF-Micro Four Thirds T Speed Booster® XL 0.64x  (model : MB_SPEF-M43-BT3/ CINE: MB_SPEF-M43-BT6)
• Canon EF-Micro Four Thirds T Speed Booster® ULTRA 0.71x II  (model : MB_SPEF-M43-BTC)
• Canon EF-Micro Four Thirds T Speed Booster® XL 0.64x II  (model : MB_SPEF-M43-BTD)
• Canon EF-Micro Four Thirds T Speed Booster® SUPER16 0.58x  (model : MB_SPEF-M43-BT7)

Disclaimer: These release notes only highlight significant changes to the firmware. There may have been other changes that are not documented.

ABOUT THIS DOWNLOAD

• Name: Firmware update V4.90 (#2179) for Canon EF to Micro Four Thirds Smart Adapter^TM/Speed Booster® 
• Release date: 14 Jan 2026
• Benefits and improvements: 
  • Fixed regression of 5-axis IBIS malfunction.

• Name: Firmware update V4.80 (#2160) for Canon EF to Micro Four Thirds Smart Adapter^TM/Speed Booster® 
• Release date: 9 Jan 2026
• Benefits and improvements: 
  • Mark II and CINE Smart Adapter only: (experimental) PDAF and IBIS improvements with selected lenses, by additional lens profile data that is specifically tailored for each lens. Visit our web site for a list of supported lenses. The LED turns pink to indicate that your lens is supported. A white LED indicates that no matching lens profile is found but it will operate in the same way as in the previous version.
  • Fixed compatibility issue with LAOWA 180mm f/4.5 1.5X Ultra Macro APO.
  • Fixed regression of IBIS malfunction with Laowa 100mm F2.8 CA-Dreamer Macro Lens
  • Corrected SP designation of some Tamron lenses in EXIF, such as Tamron SP 70-300mm f/4-5.6 VC USD A005.
  • Mark II and CINE Smart Adapter only: Fixed issue where a Canon EF-S10-18mm f/4.5-5.6 IS STM or EF-S 17-55mm f/2.8 IS USM may blackout and fail to show any aperture on OM-1. (EF-S lenses require modification to fit on a Speed Booster.)
  • "Combine OIS and ES for Panasonic" and "legacy AF for Olympus" are now 2 separate options in Metabones App; these options may disable video AF we recommend leaving them OFF; both options must be OFF to enable Blackmagic autofocus.
  • When using Blackmagic API to remote-control a Blackmagic cinema camera, there shall be no focus position updates when it is only the aperture that is being changed.
  • Mark II and CINE Smart Adapter only: add support for the Metabones API / Cooke /i board temperature command 'P' which monitors the CPU temperature.

FIRMWARE HISTORY

• More firmware history can be viewed in the archive: here

SYSTEM REQUIREMENTS:

Operating Systems

The latest version of the firmware update is compatible with most commonly-used versions of Microsoft Windows:

• Windows® 10 1809 or newer (64-bit)
• Windows® 11

A micro-USB cable is required to connect the Smart Adapter^TM or Speed Booster® to the computer.

While performing the firmware update, don't disconnect the USB cable, otherwise, the adapter may become inoperable due to sudden disconnection. In most cases, an adapter made inoperable by an interrupted firmware update can be fixed by performing the firmware update again.

Don't connect the adapter to any camara or lens while performing the firmware update.