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Understanding Light Quantity


Studio Lighting Basics


Lesson Info

Understanding Light Quantity

Let's, talk a little bit about, like, quantity. I think, like quantity is a is a topic that's not discussed enough because everybody has the world of ah, raw file that has a great range of totality is available, uh, through a cr throughout room, that whatever you're doing for for editing and you can bring up blocked up shadows and you can bring down blown up highlights. There are some things that you can do and we all know that we've been doing this now for most of us, we've been in the mainstream of digital now fifteen years. So I try. I crossed over to the dark side. They used to call it the dark side. Fifteen years ago, in july, I shot my last roll of film and, uh, and the transition was tough because the fall off the range of contrast, uh, changed a little bit. Let me let me draw something here on the board. Let me just show you, uh, give you a little bit of an insight on this. This this curve of highlight to shadow. So in the world of film this fall off was kind of like this. So t...

his would be the bottom are what they called in those days that would be the toe of the film. And up here this was the shadow of the found this is the high life area up here. Well, the distance from there to there you know, if you look at it that way was about like that. So so you got this dynamic range with a certain distance from highlight to shadow digital comes along. I like in a racer that actually works. I'm real weird. I've got a couple of little idiosyncrasies. I hate things that I only have one job and they don't do it very well, like on a racer, all they do is erased. I think half of don't work it's the only job how come they don't work? Okay, sorry, I'm weird like that. So digital comes along and the whole range of dynamic range of contrast changed. I've still got the shoulder and I've still got the tow, but the range is closer together, right? I had to discover this along the way. We all did all of a sudden everybody's blown out there highlights and they're blocking up the shadows and nobody can figure out what's going on holy moly! And then some people say, I'll never I hate this one! Go back to my film, don't do that get a handle on the digital and there's nothing better than the digital I would never shoot a roll of film again I really I've bought film and I keep thinking okay, I'm gonna go get it I'm going to start shooting some films and I'd never do it because it's just too much trouble I mean, I used to have to shoot a roll of film I don't have a lab in my town a pro lab that would process one twenty two, twenty films so my my my world was all about shooting roll film put in an envelope a prepaid envelope sent it off to my lab and I waited two weeks for the film to come back with the five by five proofs for my square format hostile blood cameras. Then when my client would place the order, then I would send the negative back to the lab and then it was four weeks before the finish order would come back. So it's six weeks in production time, plus the amount of time that the client was making their decisions. It was two, three, four months before I could deliver and build them for the job capitalist pig. Remember gotta find a way to get some money coming in the door and that took forever that process. So but my point is this that dynamic range has changed, and this is the mount much, much more narrow, so take a look at this next slide and let's talk about this for a second so here here is the I like to think of this is the five stops of usable contrast, meaning usable, meaning that that there's detail from highlight to shadow look at this next, so approximately five stops or values of life on the photographic paper, this is not what the camera can hold. This is not what your eye can see. This is what the paper can hold. How much do you think you can see? Any ideas? You can see almost twenty stops of light, subtle changes in about twenty stops, and you know that if you're ever going to a movie theater on a saturday afternoon on a bright, sunny day, when you walk in from the parking lot in the movie theater, we're carrying your popcorn in your big fat diet coke with extra because that's, where you're supposed to order and your popcorn filled with imminent as you walk in the theater, you're I just went from f thirty two and you walk into the theater and it is so dark, your eyes still down here somewhere closed, and you've got to stand there and wait and wait, and you're looking to screen just begging for a brightly lit scene in the film or the commercial so that your aiken slowly a jeff, so you can even find out if there's any place to sit. Right? You guys know what I'm talking about? You know me stops there are difference from that dark, dark dark room to that bright, bright, bright life uh lot and your eye eventually adjust because you get that auto exposure thing you got that auto iris thing going on it'll open up open up, open up until you can find the seat and then it still continues to open up until you can recognise your neighbor two or three rows down right that's what your aiken do your camera? How much do you think your camera can hold? How many? How many values or stops of of contrast you think your camera can hold from like the black? Any ideas? Any guesses? Does anybody speak? I'm just curious. I think probably six, seven, eight, nine some people say some of the higher in cameras can shoot eight nine some six some it doesn't matter the point is everything that you do. You have to think with the end in mind how's this going to be used? What are you going to make a print? Well, if you're gonna make a print, then you better control this toe within those five stops because anything else out of that is going to fall apart if you think about it h t percent gray is mid range it's the midpoint of the log rhythmic curve and that's the way photography is based on a log rhythmic right so that it's not fifty percent great it would be fifty percent grave we didn't have this world of of this log rhythmic that we live by where every number is doubled as opposed to every number you add one where you know it's not one two, three, four, five, six seven it's one, two, four eight, sixteen thirty two that's the way we live and as a result of that that puts eighteen percent gray middle gray right about there okay, so that when you open up and that's middle grade ten percent one opened up one stop that puts it right about there that's about thirty six percent on the curve this is on this dynamic range curve that's what? I came up with it I didn't make this up you guys this is just tested and and I found this to be as true as I can get. If I open up again and double the double the brightness I got to go up to seventy two percent which puts me right about there seventy two percent and that's way up there with its white with detail at plus two above mid range eighteen percent close that down cut that in half two there that's about nine percent cut it down again four and a half percent that's black with detail that's where this all comes from I didn't you know like I say this is I didn't make the news I'm just reporting the news here but it's funny that that scale right there and knowing that this fall off works right here all of it I cannot keep in perspective and I use a light meter more than anybody that I know I have friends I have friends who are high end photographers who will never use a light meter and some have been on the show and and uh and we battle back and forth and I'll tell them everyone smoking on thatjob I didn't use a meter and now they'll tell me on the job okay, well I did oh no one you know so it's really funny we have these ongoing battles it doesn't matter whatever works for you works for you, but for me I'm like I'm like a carpenter without a measuring to tape if I don't have my meter with me how can I measure this with of that cabinet that I'm about to cut if I don't know what the exposure's going to be? How can I guess eighteen if how can I guess f eleven I can't guess at eleven so just something I just wanted to chime in and let everyone know that we are going to be doing a light metering demo on our third day of this class so we are looking forward to that we always get a lot of questions about light meters and like you said, a lot of folks don't use them so tune in if that's something that you want to learn and I won't be using them today this afternoon and I'll be talking about the exposure that I'm used and that I'm getting in why I'm getting it but we're going a little bit more death assed way move on through the week so yeah, thanks for bringing it up who so this just makes sense and once you master this what you'll find is you never miss an exposure again and that's my point my point is I am all dialed in and I don't miss my exposure's ever and I'm not genius I just do it works and I do it the same way every single time I take a picture so I can't fail the pictures that you're going to see when the when the guys in the control room here run these video segments on wednesday they put all these still pictures into the video there my raw files while we're on location they just grabbed my cf card out of my camera I didn't touch him so these air you're seeing the real skinny here um and they look pretty good so I mean I would go in, enhance a few things and make a few little small corrections but not because I miss exposure of color rounds so okay doesn't make sense so far any questions about that? This would be a really good time to ask him so I don't work questions anyone? Well, I actually had a question from a little bit before when we were talking about light modifiers I see a lot of people treating uh dr boxes and peel ums parabolic modifiers as somewhat interchangeable um can you talk a little bit about you know what when you would prefer one over the other and why yeah yes oh unlocked a bank I think is knocked a bank is a lot more of a large round octa shaped soft box whereas appeal m type thing or any kind of a satellite type thing uh if I remove the front skin from that octa for example it's a different like quality it is uh uh it is a much more it has a much, much snappier look it's a much more commercial look uh it's a lot less forgiving light and you better know what you're doing when you pull one out because it can get you in trouble real quick but when done right it's just like the beauty dish it works beautifully again like an umbrella these things do stand light everywhere and if you don't have a soft grid are some way of controlling the light it does kind of spill and get away from you I have done. I've got some portrait's with the big eight footers and seven footers with only one source at full length of my models and they looked brilliant. Uh, it's, just a nice, nice source, but that silver lining on those really, really goes a long way toward helping you large and soft, yet still snapping crisp and I guess that's the word for it it's kind of crisp and has a look that you know, some soft boxes and dr banks no, no different as you get him too close and they get too big, they get what I call a little bit mushy. We don't want to get mushy. We just want to get a little bit soft. So there's a difference between soft and mushy and sometimes that silver lined, plm looking satellite look king source. And in my new world of ellen chrome there's one called the light motive and the light motive is this big giant thing with instead of octa it's got sixteen runs it's almost a perfect circle and the catch light is unbelievable. I this light source. So we'll talk about a little bit further as we go into the week, but, uh yeah, I know it's just it's it's just under again it's, you got to do the testing and we're going to talk a lot about how we do a lot of testing later in the week I brought I brought a special model that's got his own shipping case over there and we'll talk about him a little bit later in the week so um so yes so here's the here's the situation with the meter and that is watch this this is this is where what I do with my my handheld meat I'm using this iconic uh l seven fifty eight d r which I think is the smartest meter in the world is dean collins used to say it's the smartest man in the world until you drop it and then it becomes the stupidest meter in the world but when you're not dropping it, they works pretty well and what I've always done is I've always aimed to the dome of my meter toward my primary source of illumination. In other words, in other words, if I've only got one light on the set, I want to make sure that there's no shadows on the dome and the only way to make sure there are no shadows on the dome is toe aim the dome toward the source and then if I do what the meter says I don't ever missing and the argument is well, wait a minute, wait a minute we were always told your full statement at the camera okay, camera works fine as long as your main light is within forty five degrees of the camera but if your line is off camera further over and you came back to the camera going over expose your file you can save it but you're gonna miss dinner with your family so what's the point I want to use the meter and do it right the first time you don't have to fix it later so we'll talk a lot more about meeting like a czar as we go on through the week but know that I know that it is a control and it is a tool that I refused to work without and I've been doing this a while I can't get my exposure I can't look at bingo yeah, that looks like about sixteen sixteen sorry I'm not that good. Not many are so that's it right there and it's just great great little source a great little tool um I call it the reality meter you're in camera meter is based off of a reflective value of eighteen percent grade or average average grade between average average atonality between white and black that's what your cameras programmed weather spotter matrix metering, our center waiter or whatever it is it's based off of a reluctance value of the mid tone if you've got a bride's standing in a white dress in front of a white cake with white tablecloth in front of white curtain and your own automatic you're in trouble because the meter's going to go let me give you some more great well there's no grain this picture it's all white so you're under so you have to go over exposing your flash compensation to outsmart the smart cameras. So anyway, I hope that all makes a little bit of sense, but but the incident meter is a reality meter and always give me that kind of exposure out of the camera, which is just a dead on dead on exposure. Obviously I don't have to go through the lesson of understanding your history rams you guys all we've been doing this, we've been living with mr graham's now for several years, so we understand the quick history ram at a glance, but I do know that my work is best when that history graham has a gap on the right and a gap on the left even if it's a little gap, any gap at all will do as long as I've got a little gap right? A little gap left makes sense means that there's detail it's a full range image with full details I'm not I'm not clipping my highlights and I'm not blocking out my shadows on the left so you're you're going for your blacks to be that four and a half percent instead of a full black depends on the job there are some jobs that require, and I really want that that I really want the impact of the darker shadows and let him go to black I don't care, but I'm not gonna let my highlights burnout ever, but I have no problem letting the left block up a little bit, no problem, but but not the right. Okay, that makes sense, okay, there's a little feature that is a small, little known feature that most people don't know about, and I'm not gonna dig into it a lot right now because we're gonna have time, but we will throw out this week, and that is on that meter right there. If you look there's a little tiny percentage number that pops on that percentage number is all the all of the meters from psychotic and what's great about it is it tells me what the percentage of flash is relative to the ambience, so if I'm outdoors and I'm going to use flash and I take this and take a reading and it says whatever the number is, don't even think about the number, whatever the numbers, if it says thirty percent, I know it's going to be a phil flash if I used that after shutter speed combination, there is the twenty to thirty percent is going to give me a little bit of a feel flash and if it is, and if it says fifty percent I know it's the equal brightness of my subject and the ambiance from the flash they match and then if it says uh, seventy to eighty percent, then then my flash is very, very clearly a main light, not a feel like any longer, so I live and die by that percentage meter, yeah, question was going to say I had until very recently psychotics, lowest end meter, which like you were talking about earlier, you get what you pay for with the lower and stuff there actually is one that doesn't have that and that's the one I had, I just didn't want somebody watching you, you know, you're right there is forever to figure out that it didn't have a because I thought they all did and not all not the other brand meters have that either, but some do have, and on that one, even there's a there's a on all the flash meters there's an interesting little scale on the bottom that most people never see and there's a little tiny row of aperture numbers across the bottom that's pretty much it you'll miss it if you're not paying attention and when your flash fires it'll give you two of those little pointers ones where the aperture is and I mean and mints and one is worth flashes and you can kind of watching. Move those pointers, how far apart you wanted to be. Or just look at the percentage numbers. So, anyway, it's really, really important to understand your exposures, and that meter will be your best friend. If you do it. If you do it well and do it right, I think I can be your best friend.

Class Description

Lighting equipment doesn’t come cheap, so it is crucial you get your money’s worth. Learn how to make the most of your investments in Studio Lighting Basics with Tony Corbell.

Tony is a celebrated photographer, educator, and author. In this class, he’ll help you get more out of basic studio gear. You’ll learn:

  • How to use off-camera speedlights
  • The basics of studio lights including; mono lights and pack lights 
  • Combining studio lighting with natural light
  • The properties of light 
  • How to position lights for varied results and styles
You’ll learn practical ways to work with strobes and light shaping tools and get tips on creating the exact look you’re aiming for. Tony will also help you overcome any hesitations you have about purchasing and setting up your own lighting equipment.

If you want to get more looks out of your existing gear or want to know which gear you should invest in, don’t miss Studio Lighting Basics with Tony Corbell.