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Sigma MC-21 Lens Mount Converter/Adapter (Sigma EF to Leica L-Mount)

  • mfr: SIGMC21C
  • SKU: 89E969
In Stock
On Sale | 8% OFF
EDU Discount Available

Available options:

  • Free standard shipping

    *Orders placed before 3 PM EST Mon - Thur will ship the same day. Orders placed beyond these hours will be shipped the next business day. Exclusions apply. See shipping policy

  • Free Local Pickup

    Please call for store stock availability.

    Requests made before 2:30 PM EST can be available for next-day pickup. Learn more

Additional options:

Product highlights

  • Converts Sigma's Canon EF lenses to Leica L bodies
  • For use with Leica L-mount camera body
  • Expands Sigma lens compatibility list to 29
  • Optimizes AF drive, aperture control and other functions
  • Easy to use, informative interface with LED display
  • No firmware updates necessary for converter
  • Interior flocking prevents internal reflections
  • Retains EXIF data for lens settings
  • Includes tripod socket for your lens

Sigma MC-21 Lens Mount Converter/Adapter (Sigma EF to Leica L-Mount)

Leica camera owners with L-Mount systems rejoice! The Mount Converter MC-21 allows you to use your Sigma Canon EF-mount compatible interchangeable lenses with the Leica L-mount camera body. The gadget incorporates the digital data necessary to provide fast and smooth AF for compatible lenses as well as OS features and functions of the camera that help control peripheral brightness, correct transverse chromatic aberration and distortion.

Ideal for Professionals

Mount Converter MC-21 is ideal for professional photographers who use different camera systems depending on the subject, as well as amateur photographers who enjoy using a variety of camera systems. Increasing the compatibility of lenses with different camera systems makes these assets more valuable than ever.

29 Lenses Compatible

The Sigma MC-21 increases the number of Sigma lenses available for Leica system camera bodies. It makes 29 interchangeable lenses usable with L-mount cameras.

It is compatible with autocrop functionality. You can mount an APS-C size image circle DC lens to a 35mm full frame sensor camera and still have immediate use for shooting.

Excellent Autofocus Performance

AF-S mode enables extremely fast, accurate and smooth autofocus performance. The MC-21 Mount Converter is not compatible with AF-C mode.

Includes Necessary Data

Mount Converter MC-21 incorporates the data necessary for each compatible lens and uses a dedicated control program to optimize AF drive, aperture control, and other functions. It is compatible with functions of the camera that maintain peripheral brightness and correct transverse chromatic aberration, distortion, and more. Future lenses will also come pre-loaded with data for operating them with the MC-21, meaning no firmware updates will be needed on the MC-21.

Easy-to-Use Interface

The LED display on the Mount Converter MC-21 makes it easy to know whether an attached lens is compatible or not. It will light when compatible. The LED also lets you know when a firmware update is available for your lens.

Exif Data Compatibility

Lens type, focal length, F number and other tags are embedded as Exif data in the image file.

Eliminates Internal Reflections

The barrel's inside surface is covered with flocking. This guards against reduced lens performance from internal reflections.

Includes Tripod Socket

The Sigma MC-21 adapter allows you to attach a tripod. This is useful when using lenses that aren't built with a tripod socket. You can mount the tripod to the MC-21's tripod socket, making your lens tripod mountable.


Converts From Canon EF
Configuration Core
Color Black


Customer Questions
No Questions


Returns are incredibly simple. Please log into your account, find your item you wish to return and follow the prompts to make a return. If you do not have an account, click here to find your order and make a return.
You will receive a full refund when you return an item in its original manufacturer’s packaging, undamaged and unmarked. If the item you are returning is priced at less than $35, you will be charged a 15% restocking fee. Please note you will not be refunded any shipping charges. 
You have 30 days to make a return. During the holiday season, from November 1 to December 31, we extend the return window to 60 days. 
If your order has been noticeably damaged in transit, we strongly recommend that you refuse delivery and notify us immediately. Claims for missing items or items damaged in transit must be made within 48 hours of delivery. If there is carrier damage, please contact [email protected] with your order number and a description of the damage. 
Oh no! Please contact our customer service team so we can resolve the issue immediately. You can call us on 1.800.221.0828, email us at [email protected], or send us a message here.  
We do not currently offer exchanges. Please return the item you purchased within 30 days and order what you’d like instead. 
If you ordered a kit, you must return all components and accessories to receive a full refund. 
If you ordered a product that included a free item, you must include the free item with your return. If not, your return will not be accepted and you will not receive a full refund. 
We currently only offer camera repairs at our Brooklyn store. The item must be dropped off and collected in person as we do not accept shipped items for repair. For more information, please call our Brooklyn store on 1.718.431.7900. 
Most items can be returned within 30 days for a full refund. Click here to read our full return policy. 

Shipping and Returns

Same Day Shipping

All orders placed by 4PM( EST), Monday through Thursday, and by 11AM (EST) on Friday, are shipped same day. Orders placed outside these times will ship the next business day. We do not ship internationally or to Puerto Rico, Guam and other US territories at this time. For more details click here.

Free Two-Day Shipping

We offer free expedited shipping on thousands of items within the continental USA (this does not include Alaska and Hawaii).

Flexible, Easy Returns

If you're not happy with your purchase for any reason, our flexible 30-day free return policy makes it easy to get a full refund. Click here to view our return policy.

Ratings and reviews

Sigma MC-21 Lens Mount Converter/Adapter (Sigma EF to Leica L-Mount)

Sigma MC-21 Lens Mount Converter/Adapter (Sigma EF to Leica L-Mount) SKU: 89E969

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