Canon Lens Hood Naming System

Okay, I know this is a mostly trivial question, but I'm a little baffled by

Canon's lens hood naming system. There is a general trend that the EW series is

for lenses starting in the wide-angle range regardless of where then end up,

the ES series is for 50mm lenses, and the ET series is for telephoto lenses.

BUT... There are odd exceptions, like the two 85mm lenses (85/1.8 = ET-65,

85/1.2L = ES-79II), the 90mm TSE (ES-65III), and the 18-55.

 

So, anybody know what's up with the exceptions?

In some cases a hood does double or treble duty, being shared between several lenses. Of course, that means it isn't optimal for all of them.

ES = Extra expenSive?

System?

This is all I know:

<br>

First letter <b>E</b> probably stands for EOS.

<br>

Second letter: W-wide / S-standard / T-tele

<br>

Number after that is the diameter of lens hood's mount on the lens.

<br>

The optional letter after the number (A/B/C/D) means the lens hood's shape.

<br>

"I" or "II" is the version of a lens hood. Versions with at least II will have black material on the inner side.

<br>

Some lens hoods have the same name because they fit 2 different lenses with good results.

***By material I mean a black cloth.

I have a bit of info on the naming conventions here:

 

http://www.lensplay.com/lenses/lens_hoods1.html

 

It is confusing. There's no way to tell if the shade is a clip-on mount (many of the early hoods were) or a bayonet mount (most of the newer hoods are) from the Canon part number.

<p>Mr. I'llnottell pretty much has it right.</p>

 

<p>The mount diameter is approximate; I have three EW-83(something) hoods, and some combinations of a lens and a hood that's nominally the right mount diameter but designed for a different lens are very snug fits (to the point where it can actually be difficult to get the hood on and off).</p>

 

<p>The optional letter is there to distinguish between mutually incompatible hoods which otherwise would have the same name; the first one has no letter, and subsequent hoods work their way through the alphabet. For instance, there are several lenses which are wide-angle lenses (and therefore use EW-## hoods) with an 83 mm mount (therefore EW-83) but which require different hoods, such as:</p>

 

<ul>

<li>20-35/3.5-4.5 (EW-83)

<li>24/1.4 (EW-83D)

<li>16-35/2.8, 17-40/4, EF-S 10-22 (EW-83E)

<li>24-70/2.8 (EW-83F)

<li>28-300 (EW-83G)

</ul>

 

<p>This is not a complete list of hoods whose names start with EW-83, but the range of focal lengths illustrates why they have to use different hoods. The 24-70 gets its own special hood, rather than sharing with the 24/1.4, because it uses an unusual zoom design in which the front element moves back toward the body as you zoom longer, allowing the use of a very long (for a 24mm lens) hood which automatically becomes deeper as you zoom longer.</p>

 

<p>As for Roman numerals, the initial release doesn't have one; subsequent releases start with II, just as with other equipment. I wouldn't want to bet that II always indicates flocking; in many cases, it does, but that's not necessarily a hard-and-fast rule. I'm not sure if the ET-65II did, for instance; I'm pretty sure the ET-65III does. Other changes that have sometimes been made in the past include allowing a bit more room around the mount so it will fit over the knurled edge of a polarizer (the original hood for the 28-105/3.5-4.5, for instance, had problems with this; the II hood didn't).</p>

 

<p>The TS-E lenses use wider hoods than their focal lengths would suggest because they're tilt/shift lenses, and so the hood has to avoid vignetting even at maximum tilt and shift. I'm not sure why the 85/1.2 uses a standard hood; it shares the same hood as its brother, the 50/1.0, but why Canon felt this was better than having each one use a hood that's specifically tailored to it, I don't know.</p>

Oh, so the exception with the 85/1.2L is due to the sharing of a hood with the discontinued 50/1.0L...

All I know is that if you search for the Canon number on the web, you will often find equally good non-Canon versions for a fraction of the price. Most of the third-party lens makers provide a lens hood, and Canon should do the same for their non-L lenses as they already do for the L ones.