Canon Broadcast Lenses at the Olympics, and Why They Can Cost Upwards of $200,000

[Vern]

Thanks for the YouTube suggestion on fluorite lenses, Talys (https://www.youtube.com/watch?v=p7hs6DiMoWQ).

In chemistry, 'almost right' can be quite wrong - don't sprinkle sodium and chlorine on your steak instead of sodium chloride!

 

[AlanF]

According to the article in Popular Science: "Fluorine is a naturally-occurring element but grows in tiny crystals, so Canon produces its own fluorine in large quantities".

Fluorine (sic) can't be a simple typo for fluorite as fluorite is not an element. Fluorine does freeze at -219.67 oC to give crystals, but that is even colder than the Canadian winter.

Well, it's PopSci : To be fair, it's a bit confusing because both fluorine and fluorite are used in high-end lenses; the former in anti-smudge coatings and the latter to create extremely-low-dispersion lens elements.

It's not the element fluorine that is used for anti-smudge compounds - fluorine gas would attack the glass. The "fluorine" used to coat the lens is a fluorinated hydrocarbon, most probably a silane.

 

[AlanF]

Popular Science: "Fluorine is a naturally-occurring element but grows in tiny crystals, so Canon produces its own fluorine in large quantities. The company has been using the material since 1969."

Maybe not - fluorine is a highly reactive and toxic gas. Fluorite is a crystalline form of calcium fluoride.

They were almost right. They could have written, "Flourine is a element that is naturally found in flourite crystals. Canon artificially produces these crystals in large quantities..."

As you pointed out, flourine is a halogen and a gas at any natural temperature on Earth. Since it reacts to water vapor, it can't be found naturally occurring in our atmosphere.

There is a very cool youtube that shows how Canon makes the crystals, hand crushes them, and takes you through the whole process of lens-making. I fluked onto it as a recommended video on my NVidia Shield, LOL.

They were not nearly right at all - the account was chemically illiterate. Fluorine reacts with many of the atmospheric gases. By the way, what is "flourine"? Is it found in bread?

 

[AJ]

OK I saw 59 lbs. but did the article ever say HOW big these are?

"It weighs 59.5 pounds, and is 10 inches wide and tall and 24 inches long."

At 800mm and f/4, the front element needs to be at least 20cm in diameter, put that into a box and you get that 10" figure.

Good Canon glass costs about $1000 per pound (e.g. Canon 600/4 costs $12k and weighs 12 pounds)
So this broadcast lens should cost $60,000 in my estimation.

 

[IglooEater]

OK I saw 59 lbs. but did the article ever say HOW big these are?

"It weighs 59.5 pounds, and is 10 inches wide and tall and 24 inches long."

At 800mm and f/4, the front element needs to be at least 20cm in diameter, put that into a box and you get that 10" figure.

Good Canon glass costs about $1000 per pound (e.g. Canon 600/4 costs $12k and weighs 12 pounds)
So this broadcast lens should cost $60,000 in my estimation.

Well now that’s an interesting way of looking at it, but that feels right within an order of magnitude.