Fotodiox Pro Lens Adapter - Compatible with B4 (2/3") ENG Cine Lenses to fit Micro Four Thirds (MFT, M4/3) Mount Mirrorless Cameras





Category: Lens Mount Adapter
- Description
- Specs
- Compatibility
- Notes
- • Mounts B4 (2/3") ENG Cine Lenses to Micro Four Thirds (MFT) mount mirrorless cameras; infinity focus or beyond allowed
- • Enhanced craftsmanship and high-tolerance construction for demanding professionals
- • Precise fit and solid connection; lens has no play, gap or wiggling when mounted on adapter and no adjustments required
- • Precision all-metal construction with chrome plated brass mounts for secure and solid fit
- • Limited 2-Year Manufacturer Warranty
This B4 adapter version is a simple mechanical adapter that lets a B4 2/3" lens mount onto a Micro-4/3 (Micro Four Thirds, MFT) camera body. There are no corrective optics built-in, so depending on the lens you attach, you will see vignetting.
This adapter gives you the ability to use your irreplaceable prime lens with your new camera and saves you the cost of purchasing new lenses. Fotodiox 'Pro' Series adapters are made with precision and pristine award standards to insure the perfect fit for your camera and lens and to endure professional use. There is No "play" between lens and Camera for a secure fit due to the leaf springs which emulate the camera body. The unique styling maintains/enhances professional appearance.
Automatic diaphragm, auto-focusing, and other functions will not operate correctly while using this adapter as it is not electronic. In this case, "stop-down mode" will need to be used when metering since the lens does not have the ability to have its aperture controlled by the camera body. Infinity focusing is guaranteed.
| Lens Mount | B4 (2/3") ENG Cine Lens |
| Body Mount | Micro Four Thirds (MFT) Cameras |
| Manufacturer | Fotodiox Inc. |
| Warranty | Limited 24-Months |
Lens Requirements: B4 mount designed for 2/3" sensor - look for a better grade lens that resolves to HD resolutions. Impossible to list them all here. Even in the SD era, there are lenses that resolve to HD quality. A little research will uncover numerous lens bargains on the secondary market. You can easily find B4 lenses on KEH, eBay, B&H, Craigslist and practically anywhere that sells used video production gear, with prices starting as low as $100.
- • Micro Four Thirds cameras have sensors that are larger than Super 16, which means you will get vignetting when you use this adapter and a B4 lens on your camera.
- • This is a manual adapter, so lens functions that rely on electronic communication with the camera body (autofocus, AE metering, image stabilization, etc.) will be disrupted.
- • Some camera models need to be set a certain way to work with our adapters or you may get a message such as 'Error Lens Not Attached - Check lens'. Please check the support articles on the Fotodiox Knowledge Base for possible solutions on a variety of camera.
- • 'Focus-By-Wire' lenses require power to engage the manual focus rings on the lens, since manual lens mount adapters do not power the lens, those lenses will not be able to focus.
- • All lenses will focus at least to infinity, some may focus a little past. If your lens is not in focus when the focusing ring is set to the infinity mark, this is due to how Focal Flange Distance (FFD) works and how we must compensate for all lenses of its mount type made over the years in different factories with slight differences in tolerance. Visually focusing using the viewfinder or camera screen is the best way to ensure proper focus - not the distance markings, as they may not match up properly.
- • Set your exposure manually or meter using your camera's Aperture Priority (stop-down) mode.
- • If your lens does not have a manual aperture control ring, the lens aperture will revert to its default position, which depending on the lens is either stopped down to its largest f-stop or opened up to its smallest f-stop.
- • All pictures are for illustration purposes only. Actual product may vary slightly due to ongoing improvements in design.
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