Dave Plowman (News) wrote:
In article ,
Mike Clarke wrote:
There was a discussion on here maybe earlier this year, maybe last
year about whether the thread on a tripod/camera was 1/4-20 Whitworth
or UNC. ISTR we got into discussions about thread angles and somebody
pointed out that Wikipedia was (allegedly) wrong.

Thing is, I can't remember who had the last word, and I can't find the
discussion on Google Groups.

It's Whitworth. I've just fished out one of my ancient cameras that dates
back to the early '50s when the standard was Whitworth.

It may have been in the UK - but the UK was never a major camera maker?

AFAIK the thread is the same everywhere. Certainly my tripod has fitted
fine on a German, a Japanese, and an American camera.

So I googled...

"I think you will find that 1/4" BSW (British Standard Whitworth) is
close enough to 1/4-20 UNC (Unified National Coarse) to be considered
interchangeable for non-critical applications such as this (if this
were an airplane, I'd think differently). The differences are out in
the third decimal place, being on the order of 0.005" or less.

This interchangeability is fortunate, since BSW is considered
obsolete and is approaching extinction (Britain having gone metric),
while the UNC should be around for a good while longer. Certainly
tooling in UNC is a lot cheaper than BSW." (this was in a discussion
about Rollei, so not toy cameras)

http://en.wikipedia.org/wiki/Tripod_%28photography%29

"The de facto standard threading for the screw that attaches the camera
to the tripod is Whitworth 1/4"-20 for small cameras or Whitworth
3/8"-16 for larger cameras. (This otherwise obsolete thread system is
similar to the Unified Thread Standard still used in the USA, but with a
different thread angle.)

Most cameras and tripods—even those manufactured and used in countries
which use the metric system exclusively—are built with Whitworth tripod
threading."

HTH

Andy