Firmware update for Contax 645/ Contax N-E Smart Adapter and Contax N-E Speed Booster ULTRA (Windows)

Firmware upgrade for Contax 645-E Smart Adapter^TM, Contax N-E Smart Adapter^TM and Contax N-E Speed Booster® ULTRA

RELEVANT PRODUCTS

This information is for the following models:

• Contax N-E Smart Adapter^TM (model number MB_CN-E-BT1)
• Contax N-E Speed Booster^® ULTRA (model number MB_SPCN-E-BT1)
• Contax 645-E Smart Adapter^TM (model number MB_C645-E-BM1)

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

ABOUT THIS DOWNLOAD

• Name: Firmware update V5.00 (#2041) for Contax 645/ Contax N-E Smart Adapter^TM  and Contax N-E Speed Booster® ULTRA
• Release date: 10 Oct 2025
• Benefits and improvements: 
  • Fixed regression of incorrect exposure when silent shutter is used in conjuction with certain continuous drive modes.
  • After updating Contax N/645-E Speed Booster/Smart Adapter to v4.00, Metabones App gives an error when trying to upgrade or downgrade to another version. Attach USB while holding down the push button on the adapter to update to v5.00.
  • Fixed issue with W-T scale/focal length display sometimes not updating on A7 Mark IV when the zoom ring is turned. (This is an Advanced-mode-only feature.)
  • Fixed issue with video AF occasionally becoming unresponsive.
  • Improved video PDAF and advanced mode AF-C PDAF performance at the corners and the edges of the frame.

FIRMWARE HISTORY:

• Name: Firmware update V4.00 (#2001) for Contax 645/ Contax N-E Smart Adapter^TM  and Contax N-E Speed Booster® ULTRA
• Release date: 1 Sept 2025
• Benefits and improvements: 
  • Fixed incorrect distance scale display when set to manual focus. 
  • Enhanced phase-detection autofocus in video mode. Check 'Enable continuous video AF, a.k.a. "Advanced" mode' in Metabones App to activate.

• Name: Firmware update V3.00 (#853) for Contax N-E Smart Adapter^TM  and Contax N-E Speed Booster® ULTRA
• Release date: 11 Nov 2022
• Benefits and improvements: 
  • PDAF performance improvement for A7 Mark III
  • Fixed incessant hunting with Planar 1,4/50 on Speed Booster. Camera is unable to autofocus at f/1.0 and the remedy is to display the unboosted aperture, f/1.4, instead.

• Name: Firmware update V2.00 for Contax N-E Smart Adapter^TM  and Contax N-E Speed Booster® ULTRA
• Release date: 10 May 2019
• Benefits and improvements: 
  • Fixed focus issue when Drive Mode is M (medium) or H (high) and Focus Area is set to Tracking on Sony A9 (ILCE-9) after upgrading camera firmware to 5.0. (NOTE: no autofocus between frames in Advanced Mode. Use Green Mode for AF-C still photography.)

• Name: Firmware update V1.00 for Contax N-E Smart Adapter^TM and Contax N-E Speed Booster® ULTRA
• Initial date: 10 Sep 2018

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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.