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Fundamentals of Photography

Lesson 30 of 107

Light Meter Basics


Fundamentals of Photography

Lesson 30 of 107

Light Meter Basics


Lesson Info

Light Meter Basics

Alright, in this section we're gonna be talking about exposure, which means shutter speeds, apertures, ISOs, and a bunch of other things as well. And so there's a lot of things to talk about. This is, as I said, I think it's the crux of the class. So here's a list of the things that we're gonna be talking about in here and... Let's start off with a light meter basics. So all of your cameras have light meters on them. Now, what's really important to a photographer is they wanna know how much light is landing on their subject. If we know that, we will know exactly the right combination of exposure settings to get a perfect exposure. Back in the day, we used to use a handheld light meter. This Incident light meter. And they still sell these. You can still buy them. And you can go out and you basically go up to your subject, you press the little metering button on it, and it's gonna tell you right there in clear numbers what ISO, what shutter speed, and what aperture to get the absolute pe...

rfect exposure because it knows exactly how much light is reaching that subject. But walking up to your subject is not always so easy, especially if you're photographing a mountain, you know. You gotta walk a long ways to get there. It's fine if you're shooting a portrait, but it's not very convenient. And so what cameras have these days, and for many, many years is a Reflected light meter. And what it does is it measures the light bouncing off of our subject going to the camera. Now this is not as accurate because now we have two sources. We have our light source and then how much light is reflected by our subject. And our camera doesn't understand what the values and factors are of these. Now, the metering system in your camera is located probably pretty close to the focusing system for a lot of the SLRS. With the mirrorless, it's slightly different. It's taking it off the sensor, but there's a sub mirror behind the main mirror where it's reading this sort of light as you are actively looking through the camera. Mirrorless cameras are just doing it off the sensor. Now what they're doing is they're basing what they see as far as the amount of light coming in your camera. It's based off of the Kodak 18% gray card. At least Kodak used to sell an 18% gray card when Kodak was a thing. But it's based off of a middle tone gray 'cause it was figured that the world is kind of average about that brightness. And so, it's a good middle tone brightness, but clearly not everything is middle tone gray. If you are shooting something that's gray then it's perfect. This middle tone is gonna give you a perfect exposure in the background. The lights, the darks you're all gonna see, perfect. Where things get a little bit more difficult and challenging is when you're photographing something that's really dark. What's happens is less light gets to your camera. The light meter in your camera says, oh my gosh this thing is dark. And then your camera using that information goes, well we better change shutter speeds, apertures, ISOs or something so that we get a neutral gray medium brightness subject. And so it wants to correct for this sort of problem. And it wants to lighten the subject up, and it lightens everything else around it up. And so if you're photographing something that's really bright, too much light is getting back to the camera and it's thinking, oh my gosh too much light. Let's darken this because nothing is really this bright, and it wants to average it back down, and what's gonna happen is it's gonna darken it, and everything around it. Which is why sometimes you photograph pictures in the snow, the snow seems kind of dark and dingy, and it isn't as bright as it should be. The camera doesn't understand snow is different than grass or anything else. And so what you have to be aware of as a photographer are things that are darker than average, and lighter than average. The metering systems are pretty sophisticated these days, so they're really good, but you just have to be aware of these situations that kind of fallout of the standard norm of what the camera is expecting. Now the way that this light meter works in your camera, and the way that you get to interact with it is in your viewfinder on most cameras down along the bottom, there's gonna be what is known as a Graphic Light Meter, which means there's gonna be a little indicator that's gonna move off to the side like this if it is overexposed by one stop. It might look like this if it is underexposed by two stops, and then there's the third stop increments in there as well. And then if it's right in the middle, that's where you're getting your even exposure. Now there are some cameras that don't use a Graphic Light Meter, they use a Numeric Light Meter, and it's just simply a number. And it would tell you if you're one stop overexposed, you're plus one. And if you are underexposed by two, it's minus two. And so if you have to pay very close attention to which number that is 'cause there can be a lot of different numbers in there that mean different things. And if you're at proper exposure, it's just zero. I prefer the Graphic Light Meter, because it's nice and visual, and I think those things are easier to work with. So take a look and your camera and see how your camera is reading the light. Now the way it reads the light in your camera is with the metering mode that you have selected, and most cameras will have two or three, or sometimes more modes selected. The traditional mode that was on most cameras to begin with was a Center-weighted mode. This was kind of the simplest metering system that they could develop. It's a little bit more sensitive in the middle, and less sensitive out on the edges. And so usually is measuring about 60% of the information on the inside, and the other 40% on the stuff that's on the outside of the circle. So it's just weighted more towards the center of the frame. And this was good for subjects that was of average brightness, and in the middle of the frame. Photographers then wanted to be a little bit more precise about subjects that did not fill up the frame. So the next thing we had was Spot meters. And so this was really good for smaller subjects that might be in front of a dark or light background. We can now measure the light on that one particular subject. And so Spot meters have been very, very useful for photographs in the past. For portrait photography, they might measure the skin tones knowing that skin tones are usually around middle tone gray, sometimes one stop brighter. They could very precisely dial in what shutter speeds and apertures they wanted. Landscape photographers would take a Spot meter out, and they would take multiple readings of the highlight areas, the shadow areas, and they would figure out the range of brightness that they are recording in one particular shot, and then they would select their exposure wherever they need to in that setting. And this could be a very time consuming project doing this, and then figuring it out, dialing it in and so it's not, you know, for your real quick picture taking but it was very, very accurate. Nowadays, one of the most popular metering systems is what I would generally call a Multi-Segment metering system. And what it does is it breaks the scene up into a lot of different areas, essentially Spot meters, and then it compares and contrasts each of these little boxes and builds an algorithm for what the entire scene looks like. And what it can do is it can kind of disregard one errant, right spot, or dark spot, but it gets a better understanding of the total brightness and the brightness variance from one area to the rest of the scene. And this is the type of system that will be accurate or close to accurate a very, very high percentage of the time. So looking at the three different options here, Center-weighted is good if you have something in the middle that is of average brightness. The Spot meter can be very helpful for pin-point metering if you need to get a metering system reading off of a very small area. But for the most part, a lot of photographers like myself use the Multi-Segment metering system, which by the way, goes by a lot of different names. Canon calls it an Evaluative metering. Nikon calls it Matrix metering. I think Sony calls it Multi-Segment metering. Lot of names like that, and a lot of different symbols, but generally there's a lot of areas that it's doing that measurement. It's gonna be really good. And with the advent of digital cameras, and being able to see those images on the back of the camera. It's pretty easy to see if things are working or not. For those of you with mirrorless cameras, it's even better. You can just look at the screen, and you can see if it's too bright or too dark in many cases. And I think these kind of traditional light meter systems, may not be around forever. I think there are better ways of reading light than these, but they do a good job. And the Multi-Segment metering system is how I leave my camera most of the time, and that's because I shoot manual exposure, and I'm checking the back of the camera as we'll get into the next section. But it's gonna do a good job the predominant amount of time. Some people like to switch over to Spot once in awhile, and not too many people are using Center-weighted, but it's there for legacy reasons, and there's a few people who like that.

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.


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


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