# Sony E-mount: 18 mm flange focal distance

> What is the Sony E-mount flange focal distance?

- Category: Cameras & lenses › Lens mounts & filter threads
- Kind: Standard part
- Basis: Published numbers only (sources per row); no bayonet geometry is published, so no file
- Page: https://xemstudio.com/objects/sony-e-mount/ · JSON: https://xemstudio.com/api/geometry?object=sony-e-mount · Plain text: https://xemstudio.com/objects/sony-e-mount/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no printing tolerance added.

## Notes

- Flange focal distance is the distance from the mount's reference face to the image plane; adapters and extension tubes must add exactly the difference between two mounts' flange distances to keep infinity focus.
- No file: the bayonet's lug widths, angles, depths and locking geometry are not published by the maker, so nothing is drawn. Only the published numbers are given.

## Sizes

| parameter | value | from |
|---|---|---|
| flange focal distance | 18.00 mm | Flange focal distance table; XDCAM-User |
| throat / inner diameter | not published by the maker in a source I could verify (left out) | — |
| coupling | bayonet | — |
| formats | full frame (FE) and APS-C (E) lenses share the mount | — |

## Where the files are

- Wikipedia: [Flange focal distance (table of mounts)](https://en.wikipedia.org/wiki/Flange_focal_distance) — web — CC BY-SA 4.0 (text); dimensions are facts
- XDCAM-User (Alister Chapman): [The E in E-mount stands for eighteen (18 mm flange back)](https://www.xdcam-user.com/2019/11/27/the-e-in-e-mount-stands-for-eighteen/) — web — Publisher's page; dimensions are facts

## Questions

**What is the Sony E-mount flange distance?**

18.00 mm.

## Fits with

- [Canon RF mount: 20 mm flange focal distance, 54 mm diameter](https://xemstudio.com/objects/canon-rf-mount/)
- [Nikon Z mount: 16 mm flange focal distance, 55 mm inner diameter](https://xemstudio.com/objects/nikon-z-mount/)
- [L-Mount: 20 mm flange focal distance, 51.6 mm diameter](https://xemstudio.com/objects/l-mount/)
- [Lens filter threads: M40.5 × 0.5 to M112, pitch table and thread rings](https://xemstudio.com/objects/lens-filter-threads/)