Canon Lens Hoods
Canon have a large (and confusing) number of lens hoods. The names make some sense if you know the code. They all start with an "E", presumably for "EF" and "EF-S" lenses. The next letter is a "T" for telephoto, "S" for standard or "W" for wide.
The number refers to the diameter of the hood mounting ring. On most current lenses the fitting is a bayonet type mount, but earlier lenses had a clip on system and the long telephotos secure by tightening a thumbscrew.
The letter after the number refers to a specific design ("B" is different from "C" etc.) which is related to the angle of view of the lens it can be mounted on without vignetting. So an EW83B and EW83E hood have the same mount diameter, but the EW83E covers the field of view of a 16mm lens (full frame), while the EW83B covers the field of view of a 28mm lens (full frame), and so would cause vignetting if mounted on a 16mm lens.
The final designator (a "II" or "III" ) refers to a revision of a specific design (a "III" is more recent than a "II"), but "II" and "III" versions of a given hood are usually interchangable.
The following list probably isn't complete and doesn't include many discontinued lenses, but it's a start! I'll add to it as time goes on and I get more info.
| ES62AD | EF 50 f1.8 |
| ES65 III | TSE 90 f2.8 |
| ES71 II | EF 50 f1.4 USM |
| ES79 II | EF 50 f1.0 L USM and EF 85 f1.2 L USM |
| ET54 | EF 80-200 f4.5-5.6 USM / II |
| ET60 | EF 75-300 f4.5-5.6 II / USM 2 / USM 3 |
| ET62 II | EF 100-300 f5.6 L |
| ET64 II | EF 75-300 f4-5.6 USM IS |
| ET65 III | EF 85 f1.8 USM, EF 100 f2 USM, EF 100-300 f4.5-5.6 USM, EF 75-300 f4-5.6 and EF 135 f2.8 SF |
| ET65/B | EF 70-300 f4-5.6 DO IS USM and 70-300 f4-5.6 IS USM |
| ET67 | EF 100 f2.8 Macro USM |
| ET67/B | EF-S 60 f2.8 USM Macro |
| ET74 | EF 70-200 f4 L USM |
| ET78 II | EF 180 f3.5 L USM and EF 135 f2.8 L USM |
| ET83 II | EF 70-200 f2.8 L USM |
| ET83B II | EF 200 f2.8 L USM II |
| ET83C | EF 100-400 f3.5-5.6 L USM IS |
| ET86 | EF 70-200 f2.8 L IS USM |
| ET120 | EF 300 f2.8 L IS USM and EF 400 f4 DO IS USM |
| ET123B II | EF 500 f4.5 L USM |
| ET138 | EF 500 f4 L USM IS |
| ET155 | EF 400 f2.8 L IS USM |
| ET160 | EF 600 f4 L IS USM |
| ET161 II | EF 600 f4 L USM |
| EW54 II | EF 35-80 f4-5.6 II / III / USM |
| EW60 II | EF 24 f2.8 |
| EW60B | EF 28-105 f4-5.6 USM and non USM |
| EW60C | EF 28-80 f3.5-5.6 II / USM 4 / USM 5, 28-90 f4-5.6 II / USM II, EF-S 18-55 f3.5-5.6 |
| EW60D | EF 22-55 f4-5.6 USM |
| EW62 | EF 35-80 f4-5.6 III |
| EW63 II | EF 28-105 f3.5-5.6 USM, 28 f1.8 USM |
| EW65 III | EF 28 f2.8 and EF 35 f2 |
| EW68A | EF 28-80 f3.5-5.6 USM |
| EW73 II | EF 24-85 f3.5-4.5 USM |
| EW73B | EF-S 17-85 f4-5.6 IS USM |
| EW75 II | EF 20 f2.8 USM and EF 20-35 f2.8 L |
| EW75B II | TSE 24 f2.5 L |
| EW78 II | EF 35-350 f3.5-5.6 L USM |
| EW78B II | EF 28-135 f3.5-5.6 IS USM |
| EW78C | EF 35 f1.4L USM |
| EW78D | EF 28-200 f3.5-5.6 and EF 28-200 f3.5-5.6 USM |
| EW79B | TSE 45 f2.8 |
| EW83 II | EF 20-35 f3.5-4.5 USM |
| EW83B II | EF 28-70 f2.8 L USM |
| EW83D II | EF 24 f1.4 L USM |
| EW83E | EF-S 10-22 f3.5-4.5 USM, EF 16-35 f2.8 L USM and EF 17-40 f4 L USM |
| EW83F | EF 24-70 f2.8 L |
| EW83G | EF 28-300 f3.5-5.6 L IS USM |
| EW83H | EF 24-105mm f4.0 L USM |
| EW83J | EF-S 17-55mm f2.8 IS USM |
When full frame lenses are used with APS-C cameras, their field of view is reduced (via the "focal length multiplier" or cropping effect) and so they can often be used with a deeper (and therefore more effective) lens hood. For example the EF 17-40/4L takes the EW83E hood, which is designed for full frame use. However on an APS-C DSLR like the EOS 20D/30D, you can use the deeper EW 83DII hood, designed for the 24/1.4L on full frame without fear of vignetting. You can also use the EW83H (designed for the 24-105/4L on full frame).