Samsung NX K mount adapter error in report

[Dark_Mist]

G'day,
in the news section of AP dated 23/02 there's a story about a K mount adapter being available. It goes on to say "As the adapter will increase the space between the lens and the body there will be some focal length magnification, but at the moment it is unclear quite what factor will be created."

This is just plain wrong. The increased space between the lens and the body might stop the lens from focusing to infinity but that's all. Any apparent focal length magnification will be the result of the sensor being smaller than a 35mm film frame and will affect all lenses even those mounted without an adapter.

[Wheelu]

Indeed, and the SLR based lenses will require extra space, so focusing to infinity should not be a problem.

[Benchista]

Indeed, and the SLR based lenses will require extra space, so focusing to infinity should not be a problem.

The key point is if the back focus of the lenses is correct with the adaptor in place, which is quite likely for the reasons you give. However, if not, it will require an optical element to give infinity focus, and this optical element would introduce a true focal length multiplier.

[Dark_Mist]

Good points, although an optical element should only be required if the required registration distance between the rear element and sensor is too short.

[Damien_Demolder]

Yes, sorry for the confusion. That story was written at about two in the morning after a long day. At the time I wasn't able to get it confirmed that the adapter thickness would make up the difference for the back focus of 35mm lenses (obvious, but these things need to be checked) or that the glassless unit I was looking at was a final version.