Film Vs. Digital Camera Sensor
So, there's three things you need to know to create beautiful film photos. You need to know your light, you need to know your film, and you need to know your lab. So we're gonna start with know your light. Okay, here we go. So, how is film different from a digital sensor? So, if you were to do a Google search of this, those words exactly, you'd probably pull up about 100 or so articles telling you why one medium is better than the other. I actually don't think one medium's better than the other. I think that they both have benefits, and they both have drawbacks and limitations, but they are very different, and remember when I was telling you a little bit of my story, and I said when I first started shooting digital, I knew right away, like, this isn't working. What I had done with my film for years and years and years suddenly didn't work with my digital camera, and that's because film and ... Film reads light, sees things differently than a digital sensor does, and one of the biggest ...
differences is in exposure latitude. So, with a digital camera, it's actually easy to overexpose your image, accidentally overexpose your image, lose information in your highlights and all of that. And digital photographers know this and oftentimes are taught to actually err on the side of a little bit of underexposure, right? So you don't lose those detail in the highlights and you can pull it up. That's a thing that people do. The opposite is true with film. (laughs) So, this is like a huge difference. So, most professional grade film stocks, especially professional grade color film stocks, have tremendous exposure latitude. It's crazy, and so it's actually kind of hard to lose detail in your highlights. In fact, most photographers will intentionally overexpose their film, and I'm gonna show you why in just a second, because that's not an issue, but underexpose your color film, so treat it like you're treating a digital sensor, and you're gonna end up with kind of a big muddy mess. It's not pretty, so with film, instead of erring on underexposure, you err on overexposure, which feels weird when you're first starting, but this is why. So, this is an example, this is a seven stop exposure test that I did with my digital camera and with a roll of film. I think this is Portra 400 here. And this is what I'm talking about. So, this is what would be considered the perfect exposure for both the film test and the digital test, and you can see by three stops over, he's losing his face. He's just got nostrils, which isn't a great look for anybody. (laughs) Whereas down here, when you're three stops over with the film, you're fine. There's still plenty of detail in those highlights. It looks great, whereas here, you're at your perfect exposure by under one. This is still usable, you could pull that up. This is probably still usable, honestly, if you're pulling it into Photoshop or something. But look what happens to our film. So by film, with the film, by under two, you're starting to get kinda muddy shadows, color shifts, that sort of thing, and certainly, by three, you're just at a ... Kind of a big, muddy mess, where you've got a lot of grain in the shadows, and you've got a lot of weird color shifts going in. So this is what I'm talking about. It's almost like it's opposite. So when you're going into film, you kinda have to stop thinking like a digital photographer, start thinking like a film photographer. So, I wanna show you, the next slide is an example that I did of a 10 stop exposure test, but before we do that, I just wanna warn you that it features my posing doll, Betty, and she can scare people a little. (laughs) This is not a real baby, obviously, but she sits really still, and she allows me to take her picture, and my children don't. So, anyway, this is a 10 stop exposure test, you guys, with three of my favorite color film stocks. Fuji 400H, Portra 400, Portra 800. But, I mean, isn't that amazing? So this box speed would be that perfect exposure, right? And by five stops over, you still have detail. You're not losing anything. I mean, can you imagine five stops over in a digital sensor? It would just be white, right? But I get into underexposure, and it's kind of a mess, so film has tremendous, tremendous latitude in those overexposures. There she is again, she's amazing! You're gonna see her all day. Now, I wanna show this slide for a couple of reasons. First of all, yes, you can overexpose your film all day long, and you're not gonna lose detail, but I don't want you to think that that means that you can just overexpose the heck outta your film and be fine, 'cause that's not actually true either. So, when you get into what's considered extreme overexposure, so when you are at plus five, plus six, plus seven, you're not gonna lose detail in the highlights, but you are going to start to get some color shifts. You're gonna get this kinda increase grain, a little bit of color shifts. Fuji will go magenta, Portra will go kinda yellow-orange, Portra 800, depending on its scan, can go either way. So, there is this kind of sweet spot for overexposure, and I think that this is important to learn for a lot of reasons, but one is, I read this all the time on forums, where people say that they want their film to have this bright, light, airy look, right? So the theory goes, "Okay, I want light and airy, because it's pretty, and it's kind of like what's fashionable right now, so to get that look, I'm gonna overexpose the heck outta my film to get light and airy," and that makes sense if you're thinking like a digital photographer, 'cause that's exactly what happens with a digital sensor when you overexpose. So, example, what I'm talking about. So, taken moments apart, exact same light, exact same settings. These images are technically overexposed about three stops. So, blown out, bright, so that's why people think, like, "Okay, well, if I really overexpose my color film, I'm gonna get these light and airy images." But that's actually not necessarily true, because here's three stops over, and it's looking fine. So, isn't that amazing? So, then the question is ... So, if overexposure doesn't necessarily make light and airy, then what is going on there? Well, we're gonna get into this in a minute, but if you really want bright, light, airy images, that has a lot more to do with how your film is scanned, and what your lab is doing, more than it does with how you're overexposing your images, so then the question is, "Well, okay, well, if that's the case, if overexposing my film doesn't have anything to do, necessarily, with creating a light, bright, airy image, then why do film photographers overexpose their film all the time? Why are we even doing this, right?" Well the answer is because, when you're working with film ... There's Betty! It's more about the information that you're putting on your negative when you overexpose. So, when you overexpose with the digital sensor, you lose information on the sensor. That's why you blow things out. When you overexpose the right amount with a film negative, however, you actually add information to the negative. You create what's called a dense negative, and this is what that looks like. So, again, we have perfect exposure here, and you see how, as we go into overexposure, the negatives get darker and darker? It's creating negative density. It's almost like a thicker negative, like a negative is a real live thing, right? And so, especially when you're in this window, which is kind of the sweet spot for overexposure, you can see, if you look at the negative, that when you're overexposing, plus two's kinda my sweet spot, you have detail in your highlights, which you want, you're not blowing detail, but you also have a ton of detail in your shadows, which you want. That's why you're overexposing your negs, so you have detail in both your highlights and your shadows, which is gonna give your lab more information to use when scanning, or it's gonna give you more information to use when printing, if you're doing your own printing. Now, but look here, box speed, when you start underexposing, you create what's called a thin negative, which means you're losing detail. So, again, this is kind of how film and digital sensors are opposite. So you can see here, at minus one, we still have some detail in the shadows, but by the time you're down here, there's just nothing left, and that's why you get that weird grain that comes through. Here's another view of it, so you can really see it. So, again, box speed, this is a great exposure. You've got highlights, you got shadows, you got detail, but if you look over here at plus two, you can see every little hair. You just have a little bit more detail in that shadow. And here, you've got that real thin negative. So, isn't that fascinating? So, when overexposing your film, when shooting your film, the key, then, is to overexpose so that you're creating a good, dense negative, 'cause that's what you want, without overexposing so much that you're introducing color shifts or increase grain. Does that make sense? So, how do we do that, right? Okay, well there's a lot of different ways that you can do that. A lot of people will overexpose by just simply rating their film at something different. So, I dunno how many of you read film forums or film boards. People talk about this all the time. They're like, "Oh, I'm shooting Fuji, I'm gonna rate it at this, and then I'm gonna do this, and I'm gonna ..." And it gets really complicated really fast. Lemme just explain what rating means first, and then I'll tell you how I do it. So, when you're rating ... So, box speed of your film. Your film's gonna come to you with a number on it. So you get a box of film, it'll say like, Portra 400 or Portra 800 or Fuji 400H. That number is the number, the ISO number, what used to be called ASA number, that was given to the film by the manufacturer that tells you that film stock's sensitivity to light. So, if you buy a 400 speed film, the film company, the manufacturer, is saying, that's a 400 speed film, this is its sensitivity to light. When you choose to rate your film something other than box speed, you are treating that film as if it has a different sensitivity to light. Does that make sense? A little bit? So if you're shooting a 400 speed film, and you want to rate it at 200 ... So, rating it, what I mean by that, is you would pick up your camera, if you are programming it in your camera, you put it in, your camera says, "This is 400 speed film," and then you go in manually and say, "Oh no, camera, this is 200 speed film." Or, you pick up your handheld light meter and it asks you to put in your ISO that you're shooting at, right? If you were putting in box speed, you put it at 400, but if you are rating it something other than box speed, you would change that number. Does that make sense? So, rate it this way, so take 400 speed, rate it at 200 or 100, and you are automatically overexposing it by a stop or two. Go the other way, and you're automatically underexposing it, depending on how many, okay? So what a lot of people will do, and you'll see that you'll read about this all the time, on the forums, is that they'll take a 400 speed film, and they say, "Okay, I'm going to rate this at 100." So, that automatically overexposes it by two stops, which would be great, I'm gonna go back for just a second to Betty here, so, they're starting here. They're saying, "Okay, I'm already overexposing it by two stops," which is great, this is a happy place for film in that overexposure. What then happens, though, and where sometimes people go wrong with this, is then they use their metering to overexpose even more, and so, either intentionally or unintentionally, they put themselves into this area of too much overexposure. Sometimes it works great, sometimes it doesn't. Honestly, it's kind of a matter of preference. I, personally, don't do that. So, what I do, is I control my overexposure with metering, I do it all with metering. So, when I am working with a film stock, I always rate my film stock at box speed, and then I control my overexposure with metering, and the reason is, is I wanna start here at box speed. And I'll show you when we get into metering, why you do it this way, but I always want this to be my starting point, because then, I can come over here, and even if there's a three stop difference between my shadows and my highlights, then my highlights are gonna be here. I'm gonna be in that perfect window for overexposure, where I'm gonna be getting a really good, dense negative, without introducing color shifts or grain. Yes?
If you're trying to underexpose or overexpose using ISO, how do you decide where to set the number if you want to add plus two, plus three, or something like that?
Yeah, that's a great question. Well, it's kind of a matter of preference. So, I recommend kinda memorizing a chart like this. In digital cameras, there are settings where you can do, like, a third stop, a half stop, you know, different increments. I like to use my brain and work in just full stops, 'cause it's easier, so you just know that if you're at 400, it's usually like the half of the film speed, so if you're at 400, and you halves it, you're at 200, then that's one stop overexposure. Does that make sense? I don't know if that's answering your question. So, as far as like how to know what to do, it's a personal preference, right? Which is kind of one of the reasons why I don't mess with rating my film. I know a lot of people do, I don't. I like things to be really simple. I always tell people I'm lazy by nature, and so I just want things to be simple and done in camera, and I don't do this, because it does get confusing, or sometimes, you're like, "Okay, I'm gonna rate my film at 100, awesome," but then suddenly, but then you put yourself in a situation where there's no way you can shoot a 100 speed film, right? So why handicap yourself? I work inside a lot, so I'm using a lot of window light. I need those extra two stops, and I know that I can be up here at and get a good reading in my shadows, which I'm gonna show you in a minute, and have perfectly exposed, so I'm not gonna do this, because I don't wanna handicap myself. Does that make sense, what I mean by that? I know that's kind of confusing. Are there any questions about this, kinda online? 'Cause I know this can be confusing.
Question had come in from Micah Armstrong, who said, "Regarding ISO, I never quite understood what sensitivity has to do with the speed, to be honest. Does it just mean that, because it's more light sensitive, it's faster at catching the light?
Yeah, that's a great question. Okay, so let me see if I can explain this. Trying to put on my teacher hat. So the ISO number tells you the light sensitivity, so it has a lot to do with how the film is made with the silver highlights and all of that, which, I don't even know if I could adequately explain that, to answer that question, so just know, the smaller the number, the less sensitive to light. So, if you see a smaller number, that means you need more light to get a good exposure on that film. Like, there's this beautiful black and white stock that Ilford makes, Pan F, and it's a 50 ISO, and it's beautiful, but it's a 50 ISO, right? So that means I need a lot of light if I'm gonna shoot that film. So that's what those numbers tell you. If you have a higher number, it's more sensitive to light, so in theory, you don't need as much light to get a good exposure for it. Does that make sense? Does that answer that question?
Yeah, thank you.
Yeah, absolutely. So, where was I? So we were talking about, okay ... How do you properly expose, then? So, the goal should always be to have your exposure area around here. You're not gonna lose your highlights here, so if you make a mistake, if something goes wrong, and you accidentally overexpose your film five or six stops, which, by the way, I've totally done, you're fine. You're not gonna lose anything. But just know that from a negative standpoint, trying to create a good negative, let's go back and look at this, you really wanna be here, 'cause you see what happens over here? Like, it almost gets to the point, the more you overexpose, your negative is almost too dense. It gets so dense that the sensor is having a hard time, the sensor has to come in on the scanner and push all that light up through that negative to get a reading, and when it's so dark it can't do that, that's why you start getting weird color shifts and increase grain.