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Fundamentals of Photography

Lesson 29 of 107

Lens Quality

John Greengo

Fundamentals of Photography

John Greengo

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Lesson Info

29. Lens Quality


Class Trailer
1 Class Introduction 23:32 2 Photographic Characteristics 06:46 3 Camera Types 03:03 4 Viewing System 22:09 5 Lens System 24:38 6 Shutter System 12:56 7 Shutter Speed Basics 10:16 8 Shutter Speed Effects 31:57
9 Camera & Lens Stabilization 11:06 10 Quiz: Shutter Speeds 07:55 11 Camera Settings Overview 16:12 12 Drive Mode & Buffer 04:24 13 Camera Settings - Details 10:21 14 Sensor Size: Basics 18:26 15 Sensor Sizes: Compared 24:52 16 The Sensor - Pixels 22:49 17 Sensor Size - ISO 26:59 18 Focal Length 11:36 19 Angle of View 31:29 20 Practicing Angle of View 04:59 21 Quiz: Focal Length 08:15 22 Fisheye Lens 12:32 23 Tilt & Shift Lens 20:37 24 Subject Zone 13:16 25 Lens Speed 09:03 26 Aperture 08:25 27 Depth of Field (DOF) 21:46 28 Quiz: Apertures 08:22 29 Lens Quality 07:06 30 Light Meter Basics 09:04 31 Histogram 11:48 32 Quiz: Histogram 09:07 33 Dynamic Range 07:25 34 Exposure Modes 35:15 35 Sunny 16 Rule 04:31 36 Exposure Bracketing 08:08 37 Exposure Values 20:01 38 Quiz: Exposure 20:44 39 Focusing Basics 13:08 40 Auto Focus (AF) 24:39 41 Focus Points 17:18 42 Focus Tracking 19:26 43 Focusing Q&A 06:40 44 Manual Focus 07:14 45 Digital Focus Assistance 07:35 46 Shutter Speeds & Depth of Field (DOF) 05:18 47 Quiz: Depth of Field 15:54 48 DOF Preview & Focusing Screens 04:55 49 Lens Sharpness 11:08 50 Camera Movement 11:29 51 Advanced Techniques 15:15 52 Quiz: Hyperfocal Distance 07:14 53 Auto Focus Calibration 05:15 54 Focus Stacking 07:58 55 Quiz: Focus Problems 18:54 56 Camera Accessories 32:41 57 Lens Accessories 29:24 58 Lens Adaptors & Cleaning 13:14 59 Macro 13:02 60 Flash & Lighting 04:47 61 Tripods 14:13 62 Cases 06:07 63 Being a Photographer 11:29 64 Natural Light: Direct Sunlight 28:37 65 Natural Light: Indirect Sunlight 15:57 66 Natural Light: Mixed 04:20 67 Twilight: Sunrise & Sunset Light 22:21 68 Cloud & Color Pop: Sunrise & Sunset Light 06:40 69 Silhouette & Starburst: Sunrise & Sunset Light 07:28 70 Golden Hour: Sunrise & Sunset Light 07:52 71 Quiz: Lighting 05:02 72 Light Management 10:46 73 Flash Fundamentals 12:06 74 Speedlights 04:12 75 Built-In & Add-On Flash 10:47 76 Off-Camera Flash 25:48 77 Off-Camera Flash For Portraits 15:36 78 Advanced Flash Techniques 08:22 79 Editing Assessments & Goals 08:57 80 Editing Set-Up 06:59 81 Importing Images 03:59 82 Organizing Your Images 32:41 83 Culling Images 13:57 84 Categories of Development 30:59 85 Adjusting Exposure 08:03 86 Remove Distractions 04:02 87 Cropping Your Images 09:53 88 Composition Basics 26:36 89 Point of View 28:56 90 Angle of View 14:35 91 Subject Placement 23:22 92 Framing Your Shot 07:27 93 Foreground & Background & Scale 03:51 94 Rule of Odds 05:00 95 Bad Composition 07:31 96 Multi-Shot Techniques 19:08 97 Pixel Shift, Time Lapse, Selective Cloning & Noise Reduction 12:24 98 Human Vision vs The Camera 23:32 99 Visual Perception 10:43 100 Quiz: Visual Balance 14:05 101 Visual Drama 16:45 102 Elements of Design 09:24 103 Texture & Negative Space 03:57 104 Black & White & Color 10:33 105 The Photographic Process 09:08 106 Working the Shot 25:29 107 What Makes a Great Photograph? 07:01

Lesson Info

Lens Quality

All right, a final little section here on lens quality. And so we talked about the angle of view, we talked about the aperture, but there's also a few things that impact the image quality that you're gonna get from any particular lens. So, first off, we wanna talk about some of these optical challenges in making lenses. And we wanna have lenses with the highest resolution possible, and there is no rating on this, as far as a number, when you buy your lens, but lenses tend to be getting sharper because we have higher resolution cameras now. And so there are some older lenses which are quite nice but on newer cameras, with higher megapixels, they don't stand up as well as they used to back in the days of film and lower resolution sensors, and so that's one of the things that we're getting just inherently in the newer lenses. Some lenses deal with flare better than other lenses, and so when light strikes the front of the lens, it causes ghosting and light hitting different parts of the se...

nsor, and so this is why you wanna use a lens hood, and why some lenses are better corrected for lens flare than others. I talked about diffraction, when we stop our aperture down. And so what happens is that, when we stop our aperture down, the light hitting those aperture blades gets diffracted, sent in slightly different directions, which causes just a little bit of blurriness. So stopping down to f22 and 32 is not recommended, unless you really need it, because it's gonna cause a loss of sharpness on any particular image. Chromatic aberration. Chromatic, color. Aberration, ghosting. Color ghosting will occur when you are shooting a solid object that has light behind it, and so as the light comes around the solid object, the light kinda gets a little misdirected, and it doesn't land in the right spot on the sensor, and you get this color ghosting. Now, this can be corrected sometimes in camera. You can turn on chromatic aberration correction, or you can do it in post-production in a program like Adobe Lightroom. Hit the checkbox and it knows what lens you have, how bad that problem is, and can automatically fix it. Or you can even go in and manually fix it, where it looks for edge lines of a certain color and corrects it and de-saturates it, basically. And so it's something that'll happen even with the best of lenses in bad conditions, you might say. Distortion is something we talked a little bit about before. Barrel distortion is more common on wide angle lenes and pin cushion distortion is a little bit more common on telephoto lenses. And all lenses should be perfectly corrected, but the reality is is that all lenses have a little bit of distortion, and to fix this, programs like Adobe Lightroom will have a little checkbox or they'll have a slider where you can fix this up later. In most images, you're not gonna notice this is a problem, but if you have buildings and straight lines, you might see that and you might wanna correct for that, if you have a lens that has a bit of an issue with these. Vignetting is something we talked about earlier. It's a darkening of the corners, and sometimes we like it and sometimes we don't like it. It depends what type of photograph it is, and what you want from the photograph. This is a problem of fast lenses, wide angle lenses, and cheap lenses. In the early days, some of you might remember, we had TVs that had rounded corners, and that's because the image was really dark and blurry in the corners, because the lenses weren't very good at getting sharp edges. So they just said, "Well, let's just make it like this." And there were some TVs that were round, because they had really bad lenses, I think, at the time, and they couldn't get anything sharp from the corners of them. The bokeh, the quality of the out of focus area, and you know your getting picky about lenses when you're worried about the bokeh of this. And I'm not even going to get into the how do you pronounce it thing. There's a whole thing on the internet about it. I call it bokeh, it's my class, that the way I like to call it. (instructor and students laughing) So, a good bokeh is gonna have a smooth and creamy out of focus area. The bad bokeh, you might be able to see an outline of the aperture, and it's a little bit more jittery and less smooth, and so this is something that some people will grade and qualify. There is no number on this, it's just more of a feeling, it looks more smooth than it does over here. On the right hand side, it's not very good. It kind of goes bright and dark very, very quickly there. And so some lenses are a little bit better than other lenses. Construction of the lens. This is really important to me. I like working with a lens that feels good in the hand, that's comfortable, that focuses smoothly, has nice click stops on the apertures, things like that. And so, metal lens mounts, because I tend to change lenses a lot. The less expensive lenses will use plastic lens mounts. I like a real focusing ring with a rubber grip on it, so that I have a good area to grab onto. Distance scales, and there's other factors in here we'll talk more about as we talk about lenses. But there are some pretty big differences between the lowest end and the highest end lenses. And so, it's not just optical quality, it's the entire quality of that entire product that you're gonna be looking at. And so, when it comes to the optical hierarchy, of what are the best lenses and what are the worst lenses, it generally falls into this category of professional prime lenses, and so a prime, like a 200mm lens, is gonna be a really high quality lens. Next up is gonna be a prime lens, just your standard 50 or 35mm lens. They're not necessarily quote unquote pro lenses, they're just prime lenses. They're gonna be very, very sharp. Next up are your professional zooms, your 24-70, 70-200, 2.8. Kind of next down on the list of sharpness are gonna be your standard zooms. Now, the difference between the 18-55 and the 200... Noticeable, but not huge. You could shoot a cover of next month's National Geographic or whatever magazine you wanna think of with any of these, would be my guess, if it's a good subject. But when you get into the pixel peeping, you will notice greater sharpness with those primes, and especially those high end primes. The lowest on the list are the superzooms, the ones that zoom a really large range, you know, the jack of all trades, master of none philosophy. If you design a lens to try to do everything, sharpness is going to suffer a little bit. And what I have found is that teleconverters will take any lens and lower it by one step on this list. And so, what you probably don't wanna do is put a teleconverter on an 18-200 superzoom lens. Kind of falls off the chart then. But, if you use it on a high quality lens, you'll be getting decent results still, but it's gonna lower it just a little bit from its original native abilities without using teleconverters. We'll talk more about teleconverters in the gadget section in this class.

Class Description

Short on time? This class is available HERE as a Fast Class, exclusively for Creator Pass subscribers.

As a photographer, you will need to master the technical basics of the camera and form an understanding of the kind of equipment you need. The Fundamentals of Digital Photography will also teach something even more important (and crucial for success) - how to bring your creative vision to fruition.

Taught by seasoned photographer John Greengo, the Fundamentals of Digital Photography places emphasis on quality visuals and experiential learning. In this course, you’ll learn:

  • How to bring together the elements of manual mode to create an evocative image: shutter speed, aperture, and image composition.
  • How to choose the right gear, and develop efficient workflow.
  • How to recognize and take advantage of beautiful natural light.

John will teach you to step back from your images and think critically about your motivations, process, and ultimate goals for your photography project. You’ll learn to analyze your vision and identify areas for growth. John will also explore the difference between the world seen by the human eye and the world seen by the camera sensor. By forming an awareness of the gap between the two, you will be able to use your equipment to its greatest potential.


a Creativelive Student

Love love all John Greengo classes! Wish to have had him decades ago with this info, but no internet then!! John is the greatest photography teacher I have seen out there, and I watch a lot of Creative Live classes and folks on YouTube too. John is so detailed and there are a ton of ah ha moments for me and I know lots of others. I think I own 4 John Greengo classes so far and want to add this one and Travel Photography!! I just drop everything to watch John on Creative Live. I wish sometime soon he would teach a Lightroom class and his knowledge on photography post editing.!!! That would probably take a LOT OF TIME but I know John would explain it soooooo good, like he does all his Photography classes!! Thank you Creative Live for having such a wonderful instructor with John Greengo!! Make more classes John, for just love them and soak it up! There is soooo much to learn and sometimes just so overwhelming. Is there anyway you might do a Motivation class!!?? Like do this button for this day, and try this technique for a week, or post this subject for this week, etc. Motivation and inspiration, and playing around with what you teach, needed so much and would be so fun.!! Just saying??? Awaiting gadgets class now, while waiting for lunch break to be over. All the filters and gadgets, oh my. Thank you thank you for all you teach John, You are truly a wonderful wonderful instructor and I would highly recommend folks listening and buying your classes.


I don't think that adjectives like beautiful, fantastic or excellent can describe the course and classes with John Greengo well enough. I've just bought my first camera and I am a total amateur but I fell in love with photography while watching the classes with John. It is fun, clear, understandable, entertaining, informative and and and. He is not only a fabulous photographer but a great teacher as well. Easy to follow, clear explanations and fantastic visuals. The only disadvantage I can list here that he is sooooo good that keeps me from going out to shoot as I am just glued to the screen. :-) Don't miss it and well worth the money invested! Thank you John!


Dear John, thanks for this outstanding classes. You are not only a great photographer and instructor, but your classes are pleasant, they are not boring, with a good sense of humor, they go straight to the point and have a good time listening to you. Please, keep teaching what you like most, and I will continue to look for your classes. And thanks for using a plain English, that it's important for people who has another language as native language. Thanks again, Juan