What is the correct way to express aperture and focal length?

[Bill Burk]

52mm equivalent? That seems to be popular these days with fewer optics actually being designed for 35mm but everyone wants to compare to it.

210mm f/5.6

If we were talking about a fluid's container... I wouldn't write ga's tank or gas's tank.

[Steve Smith]

"f/2.8" is the 'proper' way to write photographic apertures.

The 'proper' way would be the way it is marked on the front of just about every lens I have ever seen. i.e. with the aperture as a ratio.

e.g. 1:1.4 f=50mm (50mm Nikkor-S)

or 1:5.6/210 (210mm Symmar)

If we were talking about a fluid's container... I wouldn't write ga's tank or gas's tank.

I have seen a sign outside a house offering items for sale. One of the items was a Ga's barbecue.


Steve.

[E. von Hoegh]

Or F:6.8, as it is marked on one of mine.

[Eric Rose]

Do you have a binder full of optimal lenses?

[Sal Santamaura]

...Also is it "len's aperture" or "lens's aperture" for a single lens?

..."lens' aperture."

"Lens'" is the possessive plural...

"Lens" is singular. "Lenses" is plural. See Dan's response above.

...I don't think it's necessary to use an apostrophe at all, "lens aperture," meaning the aperture of the lens, is fine. But if one felt compelled to use the possessive it would be "len's aperture" when talking about a single lens.

Frank's question offered a binary choice (from which I selected one, while some other posters sidestepped) that could apply to a description reading, for example, "this lens' aperture operates smoothly after being cleaned/adjusted and is free of incorrect lubricants."

When describing a single lens, the same thing could be said completely omitting those first two words and instead beginning the statement with "aperture operates smoothly after..." Either are perfectly correct.

Unnecessary words may offer creative writing critics something to complain about, but aren't necessarily wrong.

[E. von Hoegh]

Do you have a binder full of optimal lenses?

?? Me??

[E. von Hoegh]

I have seen a sign outside a house offering items for sale. One of the items was a Ga's barbecue.


Steve.

Did someone named "Ga" live in the house?

[Steve Smith]

Did someone named "Ga" live in the house?

Possibly.

Another sign outside a café near to me was advertising on its breakfast menu, the usual sausage's, egg's and bean's but the writer obviously got carried away with his apostrophe writing and added toas't.


Steve.

[Sal Santamaura]

...Another sign outside a café near to me was advertising on its breakfast menu, the usual sausage's, egg's and bean's but the writer obviously got carried away with his apostrophe writing and added toas't...

Why on earth would the writer have used apostrophes for the plurals sausages, eggs or beans either? None of those are contractions or possessives.

[Steve Smith]

Why on earth would the writer have used apostrophes for the plurals sausages, eggs or beans either? None of those are contractions or possessives.

It's a common crime here, usually committed by shop keepers and market traders. Sometimes referred to as the greengrocers' apostrophe (I hope I put it in the right place there!).

From Wikipedia:

Superfluous apostrophes ("greengrocers' apostrophes")

Apostrophes used in a non-standard manner to form noun plurals are known as greengrocers' apostrophes or grocers' apostrophes, often called (spelled) greengrocer's apostrophes and grocer's apostrophes. They are sometimes humorously called greengrocers apostrophe's, rogue apostrophes, or idiot's apostrophes (a literal translation of the German word Deppenapostroph, which criticises the misapplication of apostrophes in Denglisch).

Some people seem to automatically write an apostrophe before an S regardless of context.


Steve.