Canon Lens Family

[My 30D with EF-S 17-55mm f/2.8 attached]

Let's talk about the lenses! Canon used to have only one product line - the ultimate EF family. Entering the digital era, Canon started to manufacture crop body cameras, at that time, it rolled out another product line - EF-S family.

EF lenses can be used in all Canon camera bodies. However, EF-S lenses can only be used on the crop camera. The kit lens that comes with Rebel family is EF-S 18-55mm IS lens. EF-S tells us this lens can NOT be used on the full frame body like EOS 5D.

Some facilities got linked to EF and EF-S links are: USM and IS.

• USM means UltroSonic Motor, this was used in some newer lenses to provide silent auto focusing. Befroe USM, the auto focusing process is very loud. There are also different USMs. The best one is the so-called "ring" USM, which gives you the fastest and the most silent focusing.
  
• IS means Image Stabilization, this is used to counter the vibration from hand held shooting. Normally IS is more important on longer zoom (like 200mm and up).

The best lenses in EF family got the designation of "L" (stands for Luxury). The most famous lens might be EF 70-200mm f/2.8 IS L. L lenses are easy to be recognized since if you look at the front unit of the lens, you will find a red ring around the lens barrel. The L lenses are built to last and their optical performance is second to none. The only down side of these L lenses is they are very expensive.

For some reason, Canon decided not award any lens in EF-S family with "L" designation, even for a very popular pro grade lens like EF-S 17-55mm f/2.8 lens. Many pros agreed EF-S has L lenses' performance but Canon just doesn't build it like a L lenses so they are not weather proof like L lenses.

In my opinion, people who own crop bodies can start with EF-S 18-55mm lens but eventually should upgrade to EF-S 17-55mm f/2.8 lens. This lens cost around $1000 but once you have it, you won't go back to the kit lens. Not only if this lens gives you much better image quality, it's f/2.8 will be very handy in low light situation.

The next lens should be EF 70-200 f/4 IS L lens. This lens costs a bit over $1000. I don't have this version but I used to have the non IS version (sold it in 2008) and I still own the f/2.8 version and you just can't go wrong with these 70-200mm lenses.

The last lens to come along should be the ultra wide lens like EF-S 10-22mm lens. I have this lens and the image quality is really good and I Really think it's at the L lens level. Due to the crop factor, this is the only ultra wide lens that can really do ultra wide angle shooting for crop body (10mm became 16mm). I think EF-S 10-22mm and EF-S 17-55mm are the best EF-S lenses in the family. I won't consider other EF-S lenses.

Many people debate whether one should buy EF-S lens considering in the future maybe all the cameras will be in full frame format. Well, Canon just released a high end crop camera 7D, looks like Canon doesn't have a plan to abandon crop body any time soon. My theory? If you need EF-S lenses, buy them without fear. Many people are with you. If one day Canon announces they won't manufacture any more crop body, that would be the time to sell the lenses on e-Bay.

The last thing, don't buy junk lenses, you definitely will regret. You can starve yourself for two years and buy a good lens but don't buy cheap lens.

Let me say it one more time, don't buy junk lenses......