คำตอบที่ 74
The above picture shows the Canon EF 70-200mm f/2.8 L IS USM Lens (left) compared to the Canon EF 100-400mm f/4.5-5.6 L IS USM Lens extended and retracted along with their lens hoods. Both lenses have Wimberley P20 Lens Plates mounted on their tripod rings. Canon L lenses generally come with a lens hood included.
Canon L lenses are top quality pieces throughout the line. They typically have wide apertures (fixed throughout the zoom range for most L zoom lenses). Canon L lenses share a rugged build quality. The build quality combined with wide minimum apertures usually result in Canon L lenses being heavy.
The image quality of the Canon L lenses is generally as good as it gets. Contrast, sharpness, color, bokeh (background/foreground blur quality), flare, CA (Chromatic Aberration) ... All are excellent. Full Frame camera body owners will especially find L series lenses to be (on average) significantly sharper toward the edges of the frame compared to lesser lenses.
In general, Canon L series lenses focus fast. The wide maximum apertures (smallest number) and fast, quiet USM motors (Ultrasonic Motors) enhance focusing speed. The Canon 85mm f/1.2 L USM Lens and the Canon EF 180mm f/3.5 L USM Macro Lens are two exceptions to this rule.
Many in the Canon L lens series are black in color. According to Canon, this reduces heat gain when a lens is used in bright, direct sunlight. White reflects more light than black - thus, less heat gain. The black lenses look great (my opinion of course), but attract attention. Again - watch for them the next time you watch a sports event on TV or in person.
Full time manual focusing (FTM) is another feature typically present in the Canon L lenses. You can let the camera autofocus, then manually adjust focus yourself prior to the shot - without lifting your finger from the shutter.
Many of the Canon L series lenses share a 77mm filter size. Because of this, sharing filters such as the B+W Circular Polarizer is possible with many of the lenses in this lineup. More space in the bag and money savings result.
Canon L lenses typically have a non-rotating front element. This is important when using certain filters.
When coupled with the right camera body (generally Canon's 1-Series bodies), many lenses in the Canon L Series provide water resistance.
