lens throat diameter

Started Jul 21, 2017 | Discussions
cosmicnode Veteran Member • Posts: 3,805
lens throat diameter

Many discussions about systems, new mounts, suitability of current mounts to add ibis and other features rely on sizes quoted on wikipedia.

https://en.wikipedia.org/wiki/Lens_mount

However the lens throat diameters are not all directly comparable, there are two dimensions involved, the first is the inner diameter of the lens mounting face and the second is the internal diameter of the mounting lugs of the bayonet.

Some of the quoted sizes on wikapedia are for the inner diameter of the lens mount face the Sony E mount is one of these, some are quoted as the inner diameter of the mounting lugs of the bayonet Nikon is one of these.

I first noticed this discrepantcy when I found that it is possible to mount a Sony bayonet onto a Nikon body, others report that dumb items such as Nikon bellows can be directly mounted onto Sony bodies, so the mounts are similar.

I propose that in order to get correct dimensions owners of various different camera systems measure these two dimensions inside the flange and list them here,

Here is the correct sizes for a Nikon F mount

inside flange mounting face 46.5mm

inside bayonet mounting lugs 44mm

You can see here that the diameter inside the bayonet lugs is around 44mm. measured with a digital vernier it is actually that and what Wikipedia says.

This is the size inside the mounting face and is reading 46.5mm this is the reading taken with a vernier, Wikipedia does not give this dimension which is directly comparable with the Sony

Please measure your mounts for these two dimensions, the more people who measure will comfirm the accuracy of other peoples measurements and lead to a better understanding of the differences between systems.

There is a discussion on the Fuji forum about why there is no IBIS compared to the Sony mount because of the mount but are the dimensions used comparable.

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Mike.
"I say we take off and nuke the entire site from orbit, it's the only way to be sure."

 cosmicnode's gear list:cosmicnode's gear list
Nikon D300 Nikon 1 V1 Nikon D800 Nikon D500 Olympus E-PL8 +12 more
Doux Vide
Doux Vide Contributing Member • Posts: 921
Re: lens throat diameter

I don't have any precision means to measure my mounts, but I can tell you that the mount diameter is NOT the reason why Fuji doesn't implement IBIS.

OP cosmicnode Veteran Member • Posts: 3,805
Re: lens throat diameter

Doux Vide wrote:

I don't have any precision means to measure my mounts, but I can tell you that the mount diameter is NOT the reason why Fuji doesn't implement IBIS.

Just take a simple measurement use a tape or a plastic ruler will do. I'm not suggesting anything about the fuji mount,I have just seen mention of comparisons with other mounts, but I would be interested in the measurements.

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Mike.
"I say we take off and nuke the entire site from orbit, it's the only way to be sure."

 cosmicnode's gear list:cosmicnode's gear list
Nikon D300 Nikon 1 V1 Nikon D800 Nikon D500 Olympus E-PL8 +12 more
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