EOS R8 Back focus distance

[Tony1965]

Does anyone know the back focus on the R8?

[shadowsports]

Hi Tony,

Can you clarify?  What are you trying toto do exactly.  Sounds like BBF but not sure.

[Tony1965]

From the face of the sensor to the flange for the lens. 

[deebatman316]

The RF Mount uses a 20mm flange distance. The diameter of the mount is 54mm which is the same as the EF/ EF-S Mount

[deebatman316]

What do you mean by back focus.

• The lens is back focusing. This is NOT possible on a Mirrorless camera. But it can happen on an SLR/ DSLR camera.
• Or do you want to setup BBF. This decouples the shutter and AF Start Button. The AF Start Button can be moved to the "AF-ON" or "★" button. 

[MikeSowsun]

“Back Focus” is sometimes used instead of Flange Focal Distance.

[Tony1965]

Does anyone know the distance from the sensor to the lens flange?

[Anonymous]

The sensor focal plane is marked on the camera body. You can measure from that mark to the lens flange. Focal Plane symbol is shown below:

[shadowsports]

Hi Tony1965,

Are you shopping for a new camera?  You have another post with a similar question:

Back focus - Canon Community

[MikeSowsun]

It looks like 2 questions have been merged. 

The distance from the sensor to the lens mount is called “Flange Focal Distance” but it can also be called “Back Focus”.

The distance is 44mm on Canon EOS SLR and DSLR cameras like the 80D.
The distance is 20mm on Canon EOS R series Mirrorless cameras like the R8.

You can find the distance for almost any camera on the Wikipedia page called Flange FocalDistance

“For an interchangeable lens camera, the flange focal distance (FFD) (also known as the flange-to-film distance, flange focal depth, flange back distance (FBD), flange focal length (FFL), back focus or register, depending on the usage and source) of a lens mount system is the distance from the mounting flange (the interlocking metal rings on the camera and the rear of the lens) to the film or image sensor plane. This value is different for different camera systems. The range of this distance, which will render an image clearly in focus within all focal lengths, is usually measured to a precision of hundredths of millimetres, and is not to be confused with depth of field.”