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Canon Lenses: The Complete Guide

Lesson 20 of 58

Canon Lens Composition


Canon Lenses: The Complete Guide

Lesson 20 of 58

Canon Lens Composition


Lesson Info

Canon Lens Composition

so beyond kind of the standard glass can and developed ultra low dispersion glass. And so dispersion is when light hits a lens and it disperses it goes off somewhere else. And we don't like that because we're losing that light source. Okay, so they designed ud glass to correct for this chromatic aberration of light hitting glass and kind of taking off doing its own thing. And so there's a full list of lenses. And for those of you who by the class and get the pdf, you don't have to write all these numbers down. You go back and you can just look at this slide number and you can pull up the whole list of these air lenses that have ud glass and one of the things I really want to make sure getting this list right current and up to date of which ones have all this in here. So this is a significant improvement over normal glass because image quality, less chromatic aberration, less dispersion of the glass as we shooting images, improved contrast, improved sharpness because of this type of gla...

ss that is in there and there's a type of class we're going to talk about next called fluoride, and this is a much cheaper glass to use in that. So it's a relatively affordable way of improving the quality of the glass of our lenses. Now, this is originally called you D, and they have since made subsequent improvements to it and they now call it Super You d class. And so, if you see super you d that's this higher in type glass. But then along came fluoride. Alright, So fluoride is a rare earth element and it isn't in a fairly elite collection of lenses that you'll see listed here on the left of your screen. And fluoride is a rather interesting element is that you're going to get pretty much know chromatic aberration at all if you use it Excellent. Let's put in all of our lenses. One fluoride element has the power of to you d elements. Awesome. We just saved money and wait by reducing the number of elements in our lands, we're gonna make our land smaller now because we're using these fluoride elements. This is great news. Love to hear about this new technology. Very low refractive index, so refract Okay, what is refract reflect and we all know what reflect ISS. We see our reflection in a mere light bounces off of a surface. Okay, When you react to something, what happens, move along. Something happens. Okay, React to that. All right, So when light hits glass dispersion refraction, it takes often into a different direction. Very low refractive index, which means the light is going where it's supposed to go very low dispersion. This is all sounding really good. Here's a problem. Natural fluoride is too small for photographic lenses. So when you find natural floor, I I don't know what exactly looks like, but it's too small to just grind it and put it in a lance. It will work out for certain types of small microscopes, but it's not big enough toe work put in a regular lens. So Canon grows their own synthetic fluoride crystals that they put in their lenses. So in case you're wondering, why does this 200 to 400 lens cost $10,000 because they're growing Gloria class crystals to put in your lands? How long does that take? I don't know, but it can take quite some time. I know there are certain lenses that take more than 18 months from the beginning of the lens curing process. And so sometimes they're working on these lens elements, and they're in bats and heating up and cooling down, going through cycles for weeks at a time. And it takes four times longer to grind a fluoride element than it does a U. D or a standard glass element. They're very fragile, and they could be broken. And so they have to be able to be mounted in very strong lenses so that they don't get moved in the wrong way. And so imagine if you're breaking four times the amount of glass every time you're trying to grind it. That's gonna increase the cost of that lens quite a bit. And so the lenses, as I say, this is a pretty lofty line of lenses that are using these fluoride elements, but you will see it listed as one of the elements that is part of that lens design

Class Description

Working with interchangeable lenses can be both exciting and daunting to all levels of photographers. Canon® Lenses: The Complete Guide with John Greengo will prepare you to select the right lens and get the most out of all of your lens investments.

John Greengo is the master of making complex photography concepts easy to understand and in this class, he’ll bring all of your Canon EOS DSLR lens options and operations into focus. 

You’ll learn about: 

  • Focal length and aperture
  • Canon zoom lenses
  • Which lens accessories to buy
  • Third-party lenses
  • Maintaining a lens system

John will cover the full range of Canon lenses, from ultra-wide to super-telephoto, zooms to primes, fisheye to perspective control. You’ll learn how to match the right lens to your needs and get insights on the best ways to use it.

Whether you are thinking about buying a new lens or just want to get the most out of what you already have, Canon Lenses: The Complete Guide with John Greengo will help you out.


  1. Class Introduction
  2. Canon Lens Basics

    John Greengo gets you up-to-speed on the basics of working with interchangeable Canon® lenses.

  3. Focal Length: Angle of View
  4. Focal Length: Normal Lenses
  5. Focal Length: Wide Angle Lenses
  6. Focal Length: Telephoto Lens
  7. Focal Length Rule of Thumb
  8. Field of View
  9. Aperture Basics
  10. Aperture: Maximum Aperture
  11. Aperture: Equivalent Focal Length
  12. Aperture: Depth of Field
  13. Aperture: Maximum Sharpness
  14. Aperture: Starburst Effect
  15. Aperture: Flare
  16. Aperture: Hyperfocal Distance
  17. Camera Mount System
  18. Canon Lens Compatibility
  19. Canon Lens Design
  20. Canon Lens Composition
  21. Canon Lens Shape
  22. Canon Lens Coating
  23. Canon Lens Focusing
  24. Lens Autofocus
  25. Canon Lens Image Stabilization
  26. Canon L Lenses
  27. Image Quality
  28. Canon Zoom Lenses: Standard
  29. Canon Super Zooms
  30. Canon Wide Zooms
  31. Canon Telephoto Zooms
  32. Prime Lens: Normal Lenses
  33. Prime Lens: Moderate Wide
  34. Prime Lens: Wide Angle
  35. Prime Lens: Ultra-Wide
  36. Prime Lens: Short Telephoto
  37. Prime Lens: Medium Telephoto
  38. Prime Lens: Super Telephoto
  39. 3rd Party Lenses Overview
  40. 3rd Party Prime Lenses
  41. 3rd Party Zoom Lenses
  42. Lens Accessories: Filters
  43. Lens Accessories: Lens Hoods
  44. Lens Accessories: Tripod Mount
  45. Lens Accessories: Extension Tubes
  46. Lens Accessories: Extenders
  47. Macro Lens: Reproduction Ratio
  48. Macro Lens: Technique and Choices
  49. Fisheye: Technique and Choices
  50. Tilt Shift: Techniques and Choices
  51. Make a Lens System Choice
  52. Choosing A Portrait Lens
  53. Choosing A Sports Lens
  54. Choosing A Landscape Lens
  55. Best Lenses for You
  56. Lens Maintenance
  57. Buying and Selling Lens
  58. What is John Greengo's Favorite Lens?



I so appreciate what a good teacher John is. I wish I would have known this much about lenses when I first started out buying my lenses. It was hard finding information about lenses. I didn't want to spend money on a lens I wouldn't use. The better understanding we have about our gear the better photographers we will be. I have never seen a class like this. Invaluable...yes I bought the class! I am really impressed with the high quality photography classes available on Creative Live!

a Creativelive Student

Have loved the other John Greengo classes I've watched & purchased - and this is another winner! Having been a high school/college science teacher, it is refreshing to take a course with someone who not only is extremely experienced, seems to be a computer having stored so much knowledge, but is equally concerned about making the information truly understandable to different levels. And he shares the information using every tool he can: slides, video, interactive presentations, and great quizzes. I learned so much about my Canon lenses - and lenses in general with their many components. I am excited about testing each of mine to see what macro ratio they handle, and especially appreciated the tutorial on testing each for their specific quirk that affects super sharpness. This class is great whether you own Canon lenses or not. Thanks John Greengo!


This was a great class not just about the lenses that Canon offers but also how each lens works. As usual, John's slides are alway informative and entertaining. There is a phrase: John has a slide for that! I am not even a Canon user and found this class to have great information for the use of each specific lens. Great work John! Thank you Creative Live for another great class!