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Lesson 4 from: The Photography Starter Kit for Beginners

John Greengo

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Lesson Info

4. ISO

Lesson Info


last section on the sensor very much related to I s O. Because we're gonna be still talking about the sensor. So I s O. And there is a little bit of controversy in the photographic world, whether it's ice so or I s O. But I'm so used to calling it I s O. That's what I'm sticking with. It is the sensitivity of the sensor, and it's basically a standard so that when you have eso in a canon or Nikon or Fuji or Sony or anything else, if you're standing there with your buddies all shooting pictures, you could have one person call out via e isso such and such a particular shutter speed in a particular aperture. And you should all get the same exposure if you're pointing your camera at the same thing. All right, so it's a standard, and we're not gonna get into it. Kind of the baseline standard for most cameras is I s 0 100 This is that what's often called the native sensitivity of the sensor? There are a number of cameras that are I s 0 200 noticeably, Leo, your Fuji camera has a some of the ...

night cons, especially older night cons have a native sensitivity of so 200. It doesn't necessarily make them better or worse. They're just different from there from I s a 100. When you move it up to 200 we're doubling the sensitivity of the sensor. That is the effective. So if you make no other change in your camera other than going from 100 to 200 I s O, your picture is gonna be twice as bright, all right? And it's not that you're letting in twice as much light. It's that the sensitivity of the sensor has been magnified. If you can kind of think about a microphone, you know, back in the back control room here, a creative life, somebody has control of my microphone. If I was to hold it out further from me, they could turn up the sensitivity. Now it might pick up some other noises, but they could change the sensitivity of the microphone. And we can do that on our cameras with the I S O setting of our camera. When we go up to 400 it's four times a sensitive, so it's a linear change. We just double the number. We double the sensitivity and so we can do that on up and up and up. And cameras, as of late have been getting very, very sensitive for low light work. The range that you're going to see might be anywhere from 50 up to 25,000. The lowest numbers are going to be the optimum image quality, and the highest numbers are going to be the highest sensitivity. So they're very good under low light conditions. So if you were to go from 400 to 800 you double the sensitivity, and we also call this a full stop of light. You need a full stop higher. I s o somebody might say you need to lower your I s 01 stop. We would go from 400 down to 1 of those feature differences between an entry level and an intermediate camera is that an intermediate level camera will have third steps on the ice cells. These aren't completely necessary, but they're kind of nice when you're trying to get very specific about making settings on your camera. And so your typical say, 600 to $800 camera may not have these options, but you'll definitely see them on cameras that cost $2000 Enough. Now, some of you will notice that numbers are either grayed out there not available, or that you have to go into the custom functions or the set up of your camera toe allow you to get into these extra high numbers, and they might rather than give you a number, Call it H one or high one. And now, frankly, this is kind of goofy. Uh, the manufacturers should just give it a number because it is a number high one, if you see it on your camera, is one stop higher than the previous number. So in the case here, if 6400 is our highest number and we have high one, it would be simply 12,800. Now, there are some cameras that have a low setting an L one or low one, And for many cameras, I s A 100 is the lowest number, so they'll have low one, which would be 50. But this varies from camera to camera. So you have to take a look at your camera to see what the ISOS that you can get you are. And on most cameras there will be a feature buried within the cameras feature set, usually under camera settings called eso expansion, and it allows you to use the extra low and extra high numbers. And I always like turning those on because it allows me to go to those areas if I need them. I generally don't need them very often, so it's not critical that you go in and turn that that option on now. Another option that all the cameras have these days is auto eso auto eso is where the camera will look at what you're doing and try to make a judgment call. What I eso is best. And in my opinion, the camera does not do a very good job at guessing the right I sl and what it's doing on how did Well, how does it How can it possibly guess what would be the best? I s. So what it does is just just one very simple little thing. It looks at the shutter speed that you have, and if your shutter speed is below 1/60 of a second which is kind of a hand holding rule of thumb. Then it just bumps up the I s. So it has no understanding if your cameras on a tripod or if you're wanting a shutter speed lower than 1/60 of a second, and so it doesn't really understand what you are doing with your camera. And if I could just step aside from this for a moment, there is nothing that your camera does automatically for you that you can't do yourself. So if you learn how to work your camera, you can outsmart, outshoot your cameras built in abilities, the processors, the computer programs that are built in they might gnome or if you don't know anything about photography. But once you start learning, you will quickly surpass the intelligence of your camera. And that's where you start making control of your camera. And so I don't recommend auto I s O for anyone who's really wanting toe learn their camera and learning how to take control of it. I kind of think of it as like an automatic driving a car. Do you think people who race cars would like automatic driving their car? Not a chance they want very specific control about what gear their car is it? And so if you want to take control of your photography, you need to take control of your S O. Granted, there are exceptions when you can use auto eso and it helps you in a short term situation. But I'm just gonna recommend Get out of it, folks, Let's go manual. Let's get serious. All right, Now with these eyes so changes I've mentioned very briefly that there's an image quality difference between shooting them. So let me show you some test shots that I did with a reasonably high end camera. And I shot it at a variety of different ISOS and we cropped in and blew this up. And frankly, you're not going to see any difference in the top row because the cameras really good and shoots all of those lower esos very easily. Let's go straight up to 25,600. In this example, you can see that it is very grainy, like this is what we call noise, and the problem is, is that the sensor is not receiving enough light and it's trying to make up information, and it's not doing a very good job of it. And so, with whatever camera you have, my general thought is that whatever your highest I eso is it's junk. You don't want to use it. And the same thing with the next highest one. You come three down from your highest isso and that's probably the highest I e isso that you will want to use If quality is pretty important in the picture. Why are these here? Emergency Bigfoot stepping off of a UFO at night time. 25,000 if I needed I'm gonna use it, OK? Because we're gonna be balanced in these with our shutter speeds. What's better? A blurry picture or a noisy picture? I don't like either one, but I really hate blurry pictures. So I would take a noisy picture, has a little bit more noise so long as its sharp and clear to see. So let's take a look at how I set I esos and for what sort of situations. When I'm doing landscape photography, my cameras on a tripod and my subject is not moving. That's when I met I s 0 100 because I want the maximum image quality from my sensor and most of our cameras. 100 is where we're gonna get maximum image quality. So if I do make a large print and I blow this up, we have very fine detailed information and no noise in the shadow areas. When do I goto s 0 200? Well, when I can't use a tripod and I'm moving around any time I go out in a boat kayak, a ferry, any sort of boat, I'm probably at I s 0 200 cause I need just a little bit of faster shutter speed. A little bit of edge in order. Help have that faster shutter speed to stop that action of the boat moving around in other things Pretty much. Any time I shoot sports, even outside indecent daylight, I go upto eso 400 because I need a faster shutter speed. And in that case, I'm gonna need that high rise. So So if you shoot sports outside is just a starting point. If you shoot indoor sports, you're easily going to be at 16. 32 or maybe even 6400 depending on how bad the lighting is in that arena. under low like lower lighting levels. I don't have too much of a problem going upto eso 800. I think any camera over the last three years has pretty clean image quality at I s 0 800 And so I'm always wanting to keep This is lowest possible, But I don't I don't fret too much going upto eso 800 because when I enlarge that, it's still very clean information. And I'm getting very good results in any shot posted on the Web or on an HD screen. You're not going to see much difference there as we get into lower light situations, especially where I have some needs with some shutter speed. These girls are dancing up here and I don't mind a little bit of blurriness, but I don't want too much that you can't tell what's going on. I s 0 1600 Now, as I start enlarging certain sections of this image, you're going to start seeing noise in the underside of the Space Needle. It looks a little chunky and it's not quite as smooth as it is in reality. And so we're starting to lose a little bit of quality here it's acceptable in that shot, but we are starting to lose it. I s 0 3200 I mentioned I was in a nightclub shooting pictures at 1/60 of a second. But this is S 0 3200 And as we enlarge this little portion of the mic, you can start to see that the mic is very rough. Looks like sandpaper because our sensor is not getting as much light as it would like to get when you reduce it down. And size is not that big a deal. I s 0 6400 This is the highest that I would shoot. I wouldn't say it on a regular basis, but I don't fear going up to 6400. But I know if I make an enlargement, look at all that noise in there. That's a very, very rough image, you might say, because we've taken that sensor all the way up to 6400. Probably wasn't the first thing you thought about when you saw the image. But be aware that you wanna stay. Keep these as low as possible. So why do we choose a specific I s Oh, well, it mostly comes down to technical reasons. If you want the optimum image quality, you keep it as low as possible. If you need a higher sensitivity, you move it up to it. So my guidelines are very, very simple. Just keep the eye isso as low as possible and the reasons that you would raise it up from the lowest setting. You have to potential reasons 99% of the time. It's because you need a faster shutter speed. But every once in a while it's because you need more depth of field. Now. We haven't explained this more depth of field part, but we'll get to that in a section or two. But most of the time when you're raising up in I A. So chances are you're thinking about. I need a faster shutter speed because I'm hand holding it or I'm trying to stop the action of something out in front of me that I'm shooting. So let's see what sort of questions this spurs yes, are the is related to the sensitivities we used to see in films you'd buy when we had film cameras. Yes, it iss exactly. If you remember by 100 speed film for a sunny weather and 400 for action and maybe for really low light. It's very much like that. It works in a slightly different way behind the scenes, but it's the same effect in the longer. The one difference I would say now is that when I was shooting film, 816 100 was considered pretty high cutting edge, low light film. Nowadays that would be 32 64 even higher. Any other questions from our in studio audience? So question from online? When do you select the eso? Is that the first thing you think of when you see a photo? Or is it the last thing you think? Think of when you see when you go to take a photo. The question Well, the shutter speed the I s o in the aperture of the three controls that a really important and a lot of times for me the I s o is the first thing I said. It has to do with the environment that I'm shooting in. If I walked outside on a beautiful hike Nice sunny day. My camera would be it. I s a 100 as I get out of the car. All right. Now, when I go into a dimly lit restaurant, I would immediately be thinking, Oh, it's really dark in here. Maybe I s 0 1600 or 3200. And so depending on the environment is kind of the first. That's one of the first settings I said. Now, a lot of times I'll find myself in a situation where it's not quite right, and I need to make some compromises, and we're gonna have a fun little time making these compromises later on, and I'll adjust it later on. But generally it's kind of like what type of pictures in my shooting right now what type of environment and light. Um, I'm working it, and I realized, for somebody who's brand new to it, they're going like I have no idea. But if you just watched what we went through, that's that's your little primer for Okay, this is probably where your eso should be out

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Ratings and Reviews


I'm not sure my first review posted. But I LOVE this class! John Greengo is a great, engaging teacher who is really adept at representing the concepts visually and excellent at explaining them verbally. I love how he goes through examples with photographs he has taken. Even though I only have a Nikon Coolpix digital camera, it does have Manual, Shutter priority, and Aperture priority modes. Through his class I've gotten a really good sense of how to balance ISO, aperture, and shutter speed. It's a great overview for me especially since I am new to photography, I can play around with some of these settings, and I have a greater understanding of what I might need in a higher level camera in the future. Money well spend! (For $29, this is an absolute steal). John Greengo is an awesome teacher and I hope to take more of his classes in the future!

Megan Wagner

John is extremely articulate and is a great teacher with lots of visual aids and metaphors to help understand photography. I have been doing photography for a few years now and this class was a tremendous help in boosting my knowledge and refreshing my memory in multiple aspects of photography. The graphics that John uses are helpful and he even goes through images and asks which settings would be best to use and will go through the why. He makes things easy to understand and is very clear about the information he provides. I am so glad I took this course and I would highly recommend it even to an experienced photographer. Thank you John Greengo!

Victoria user-245035

I am a semi retired hair stylist who is finally following her passion of photography. I have taken a class here and there and stumbled on Creative Live and realized the potential of learning is endless. Love love love the way John Greengo teaches. I am finally beginning to understand and retain so much. Thank you John, your the best. I hope one day I can meet you up close and personal. Thank you!

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