Canon L Series Lenses

This was a free two hour class offered by Canon and Keeble & Shuchat with Jennifer Wu about Canon’s L lenses by Jim Rose and nature photography tips from Jennifer. I originally heard about this from Jim when he came to COBA to discuss about CPS membership. As an added treat, Canon brought twenty four L lenses, including the Canon EF 500mm f/4L IS USM and the Canon EF 800mm f/5.6L IS USM, and five bodies (three 1D Mark IIIs, one 1Ds Mark III, one Canon XSi, and a Canon EOS 5D) for everyone to try. Also Jim brought a pre-production Canon EOS 50D with the new Canon EF 18-200mm f/3.5-5.6 IS zoom lens.

Canon EOS 1D Mark III with Canon EF 800mm f/5.6L IS USM
Canon EOS 1D Mark III with Canon EF 800mm f/5.6L IS USM

The Canon L Series Lenses

The class started off with Jim Rose discussing about what makes Canon “L” lenses so special from the normal consumer level lenses. He also confirmed that the “L” does, in fact, stand for Luxury. What defines a L lenses is the existence of:

  • Two or more Ultra-Low Dispersion (UD) elements (and/or)
  • Fluorite Element (and/or)
  • Ground and polished aspherical elements

Fluorite is a natural occurring element, but usually not enough in quantity to be useful, so Canon has developed a method to “grow” them. It takes at least two ultra-low dispersion to equal one fluorite element. The fluorite element eliminates almost all chromatic aberrations.

Wide angle lenses and “fast” lenses (f/1, f/1.2, f/1.4, f/1.8, f/2) experience spherical aberrations which causes the images not to be as sharp until they are stopped down to apertures of f/5.6 or f/8. By using aspherical elements, this counter-acts the spherical aberration effect and can also make zoom lenses smaller in size. There are three types of aspherical elements:

  • Molded aspherical element: round glass is super heated until near melting and is poured into a molding and allowed to cool thus making a molded aspherical element. This process makes creating aspherical elements cheaper, but not as good quality.
  • Replicated aspherical element: a piece of specially created resin is glued to the round glass to create an aspherical element. This types of aspherical element tends to appear in the consumer grade Canon lenses
  • Ground and polished aspherical: glass is grounded and polished until they meet the aspherical criteria. Very expensive and appears exclusively in the L line.

The Canon L lenses are designed to be durable withstanding: torrential down pour rain, extreme temperatures, snow, grueling wear and tear. All the L lenses use ring type Ultra Sonic Motor (USM) focus motors. This is the fastest type of auto focus that Canon has. Jim also spoke of the f/4 zooms (17-40mm, 24-105mm, and 70-200mm) and offering customers a choice in lighter weight equipment at a lower price with the same L quality. Jim also spoke briefly of Canon’s “S” line, the EF-S mount lenses specially designed for the crop sensors.

Jim also spoke of the tilt-shift lens and it’s uniqueness in the Canon line. Also someone in the audience had asked why only one of the three tilt-shift lenses offered by Canon is designated as a L and Jim’s response was: 1) L designation is given to lenses who fit the above requirements and 2) not all lenses require fluorite or ultra-low dispersion glass to achieve optimal quality. Thus, the 45mm and 90mm tilt-shift lenses are not L quality lenses because they do not contain fluorite or ultra-low dispersion elements.

Nature’s Elusive Beauty

Jennifer Wu

Jennifer Wu gave a great PowerPoint presentation on capturing Nature’s Elusive Beauty, the one moment in which the scene is perfect, the lighting is just right, the colors are popping, the scene is ready to be captured.

Jennifer shoots with a new Canon EOS 1Ds Mark III and a Canon EOS 5D. Her lenses are the Canon EF 17-40mm f/4L USM, Canon EF 16-35mm f/2.8L USM, Canon EF 24-70mm f/2.8L USM, and the Canon EF 70-200mm f/2.8L IS USM. She does very little post processing, usually dodging and burning and does not remove anything from the scene with Adobe Photoshop or up the saturation in anyway. She uses a circular polarizer and neutral density filters.

Some of the bullet point tips she offered:

  • Finding locations: Internet, guide books, asking the locals
  • Things to consider: seasons, fall colors at peaks, when flowers are in bloom
  • Get local advice: call ranger stations (rangers have most likely hiked every inch of the area and done it repeatably where they would know the best times to visit), visitor shops to find the answer to questions
  • Scout the area: scenic routes, pullout areas, off the side of the road
  • Get off the beaten path. Don’t just come to a pullout area, get out, take a picture, and leave. Walk around a bit, get a different angle.
  • Things to consider for photographing: weather, clouds and light (arrive before a storm-clearing storm, fog create mystery, rain-saturated colors, snow-first dusting on mountains (versus white covered mountains), wind and movement
  • How to create perspective: lens coverage, distance to subject, and camera angle
  • The lens you choose is about the type of coverage you want
  • Focus using hyperfocal distance to get things near and far in focus.
  • Always use a tripod for maximum sharpness.
  • Camera angles: look down, look up, get low. Create depth with wide angle lens by getting up really close.
  • Use ND and Polarizers. Polarizers for foilage, water, and midst
  • User manual with spot metering on 18% grey of red or blue. Aim for exact exposure, not under or over. Shoot RAW and aim for f/16.
  • Foreground elements: fill the subject with the foreground element.

One of Jennifer’s other favorite types of photography is star photography. Here are some great tips she offered for photographing stars:

  • To avoid star trails and get points of light: Take 500 divided by focal length of the lens (if you are using a crop sensor, you have to take that into account and get the actual focal length) will give you the seconds to set your camera to get points of light. Anymore and you will have star trails
  • Use wide angle lenses at 30 seconds or less.
  • Shoot at wide open aperture (f/2.8, f/1.2 if you can)
  • For moonless night, set ISO to 3200, with moon (depending on how bright), set ISO to 200-400
  • Use your ISO to change exposure and not aperture or shutter
  • Turn your camera’s noise reduction on which is great help
  • After you take a night shot, let your CMOS sensor cool down for at least 30 seconds or you may have additional noise in your picture because of the heat on the sensor
  • Set your white balance to custom kelvin from 3200-3800 to give the nice bluish sky
  • WB custom 4200 works really well at the beginning of sunset, but not at 3 AM
  • Try focusing on the brightest star and not on a tree or foreground element. If nothing to focus on, set to infinity and back off a bit.


This was a very informative free seminar sponsored by Canon. It was also an introduction course for those who signed up for the Canon Field Workshop the next day. Jennifer Wu has some absolutely stunning landscape shots and is able to articulate her technique and give steps and advice and not boring useless technical details.

As an added benefit, we were able to try all the twenty four lenses and four bodies and all the participants were given a free copy of the newly updated EF Lens Works III book that includes the new Canon Mark 3 bodies and new lenses. Awesome.


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