70-200/4 IS USM, colour of casing

[okief]

Hi, just bought this lens and was surprised the casing is not white, but a sort of light beige/khaki colour.
Is this normal...?
And really, I don't care as long as the optics are good, but white does look kind of nice...
many thanks
okief

[JM Tran]

hey there, Canon uses what it calls Putty White for that lens, its an off white colour

[okief]

thanks JM Tran
any idea why, is it to differentiate it from the non-USM perhaps?
cheers

[JM Tran]

thanks JM Tran
any idea why, is it to differentiate it from the non-USM perhaps?
cheers

According to my knowledge, the scientific approach was that the putty coloured L lenses were meant to endure harsh conditions, and its ability to reflect heat from its colour is an advantage, for not heating up the internals of the lens and its elements inside to cause warping or become un-adhesive etc. Someone here can explain it better than me anyway!

It makes sense in reality when you think about it, wearing a white shirt under the sun your body will be more cooler than wearing a black shirt which will absorb more heat and rays.

[Xenedis]

According to my knowledge, the scientific approach was that the putty coloured L lenses were meant to endure harsh conditions, and its ability to reflect heat from its colour is an advantage, for not heating up the internals of the lens and its elements inside to cause warping or become un-adhesive etc. Someone here can explain it better than me anyway!

You've basically covered it.

Most of Canon's white L-series lenses (the super-teles in particular) contain fluorite elements, and fluorite doesn't like heat!

As most people know, white reflects heat and absorbs far less than darker colours.

Of course, I'm sure that Canon also uses the distinctive white of its lenses to its advantage from a marketing perspective. People notice those lenses, even if they don't know what they are. They stand out on sporting event sidelines.

Sure, while it could help in the marketing department, the white colour has a far more practical use as explained above.

And to demonstrate, here is a post on dpreview.com showing thermal images of lenses -- both black and white:

http://forums.dpreview.com/forums/re...ssage=12671815

The heat radiation difference is quite considerable between white and black lenses left in the sun.

[la lumiere]

Didn't Canon change the colour from bright white to putty white this year?
I thought I read that the newer lenses (2nd half 2010 onwards) are the slightly darker colour
.

[Xenedis]

I've heard the mark II versions of the IS-enabled super-teles have a different colour, but I've not seen one in person yet.

I have two white teles and they're both the same colour.