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Lesson Info

Wizwow's Rope Meter

we're going to find out a single exposure on a flash single exposure because using the inverse square law that scare anybody scared the hell out of me first time I ever first of all it had the word inverse innit I'm saying it was inverse what the world is in verse and then it was squared kind of remembered squared being really kind of hard to figure out and then it was a law three in a row was very very simple to get your arms around when you can see it so we're going to see the inverse square law with this this bad but we're here and we're gonna take off a speed light and measure it just like I would for um for all my speed lights if I was to make one of these and I'm gonna try to do here is to get one exposure and we moved from this and understanding that light does the same thing every time we can figure out explosions was that saloon a pro one sixty yeah that's plenty right about here fraction work thanks sir because light does the same thing every time we can apply a very simple m...

athematical equation to at the inverse square law we can take this and do this with any and every like that we have doesn't replace your light meter boom maybe maybe if you were a little studio shooter and you had a small studio in a couple of speed lights than you were shooting with this you could create lately create one of these and never have to worry about a meter again because it's going to do the same thing every time so what we're gonna do is we're gonna find f four on this camera guys you got kind of fun what I'm doing here come back here we're gonna find f four on that flash are are we have bread away at one tenth power okay we want one eighth power when you're doing this you weren't doing the eighth power the reason is if we do it at full power we're gonna have a very long strength if we do it in eight power and and if we have a very long string the only way we can do is go down if we started an eighth we can use the same string if we want this not to be brighter we can go up a nacho down a notch zoomed huh fifteen right in the middle of his own okay and we're gonna take a flash meter reading yeah right about here four point oh free right about here who two point nine that would be great because we're gonna make up for gonna cut it right here gonna make up for a couple of inches and knots here this gives me enough for reading one eighth power the strength what if I set that on one quarter power what is it now blank faces if it goes up by one stop wait double the power from an eighth to a quarter we went up by one stop at four becomes five point six because we've doubled the power of this all of our f stops and shutter speeds are in doubles powers our main shutter speeds of death stops yes our digital cameras have thirds of a stop that's fine so if we don't have four is and we know where our light is we also know where f ate is and face in the middle two stops away from f four it's twice as close to the camera four times more light f a I said camera I met light so that's our half eight knot right here and we've got four back here somewhere between f ace and f four is what five point six where do you think that's going to be it's going to be in the middle now there's going to be somebody out there on the interwebs going to say no it's not in the middle it's five point six not six yeah it's also coming out of a speed like we're going in the middle okay trust me so I'm gonna take this little guy right here no matter what I do I wasn't doing it the wrong way okay this way way so we got four we've got five point six we've got half eight and in between the light and f ate is two stops eight eleven sixteen sixteen hoops right up here this is in the book by the way in the handbook the pdf yeah we create that here and then between sixteen and faa is eleven what I like about doing this little rope thing here is when you teach somebody something literally anything I believe you khun tell him about it you can show him a picture of it then you can let him touch it that's the inverse square law you could hold it in your hand look at the difference between us that's a whole stop here because it's farther away from the light that's a whole stop when it's closer to the light lights falling off faster closer to the light then back here we're on live television right so I'm gonna hook this here put my meter here at f a a all right give me the thumbs up should be a fate right all right oh my eight points years here eight point zero zero according my minolta flight thank you for coming everyone way have f ate at this not when I teach this at the workshops I'll have people say oh so we always find faa no no no no no this is f ate and I s o one hundred and I s o two hundred this is f eleven this is not a tool for youto always put your light in the same spot this is a real light meter so what if four at s o four hundred what is this sixteen now sixteen twenty to thirty two if this is we're backto s a one hundred this's f eight and this is half eleven where's f ten about their f nines right about there just thirds of a stop you can visually do that where's two point eight well to point a is double this so it's two point eight is here handy this becomes you set up a light you pull it out first you have to ask yourself what I want to shoot it at that's that's terrible right dangling participle there at what exposure would I like to choose to make my photograph shoot you shoot out there you make that decision based on your ambien if you're using ambien are you based he based it on what you want the photograph to accomplish do you want shallow depth of field do you want deep depth of field if I was going to do a head shot I might want shallot up the field if I was going to do a head shot with maybe two people had one a little more this's only imagine um it it doesn't mean that you always have to shoot a deaf aid or always have to shoot it f eleven here you always just simply come in and say ok if I have my subject sitting here and I have my flash their bare flash it I can shoot it at f ate what if I wanted to shoot a fooling shot obviously that can't be this close because coming in shot well we can shoot it at five point six or we can raise the so the two hundred and shooted a deaf aid here or we can raise toe for hundred and shoot it out f ate here it's just one exposure gives us everything one rope to rule them all like that the lord of the strings no way just not gonna work way have so much information here that we can use and then you take your modifiers shoot through umbrella goes where between the light and the subject right it kills two stops it was little soft boxes they killed two stops and a little diffusers they killed two stops are we seeing a pattern now some of them were going to kill the stop in a third or I mean stopping two thirds maybe they'll kill two thirty two and a third stop but believe me they're gonna get you in the ballpark and getting in the ballpark is what you want to be able to do you don't want to spend time futzing around with the light you know just take a shot and see what it looks like okay I know I've got to figure out what I'm going to do it's deliberate first we decide what we want then we place the light the light becomes a function of power and distance shutter speed does not enter into the equation we're not talking about shutter speed here were just talking about the power of the light the shutter speed does what it deals with that light the ambient light when you go to take a photograph what's the first setting you think of aperture that's being aperture first thing I have to set because it's the very first thing it's the thing on the image that you are going to see the most if it's a still photograph of a head shot I'm not going to see the difference between a sixteenth of a second two hundredths of a second in that photograph I'm not it's not going to show I'm not going to see the difference in I s so it's not gonna show but I'm to see the difference between shooting at one point eight shooting at sixteen so I choose my aperture first visualize it before I've even set my subject down visualize that aperture then I know what I need to shoot it at so in a room like this what would we do we'd probably find out what our ambiance is and then you have to make a decision where you wanna place that gambia we're going teo teo bring out a ah young lady here and we're going to start with a soft box and we'll come right back to this string real quick and I should show you how we're going to use this string but I do want to bring her out with soft box first because even though we're using a pro photo in h amira soft box this is fairly high end stuff we're going to pull it right out of the way and we're going to use my favorite lighting tool in the whole world comes from target or tar jay as my wife likes to say hey shower curtain liner and you always buy the cloth shower curtain liners if you buy the plastic shower curtain liners two things happened number one machi three things happened but I can't talk about the fire legal thing you know you signed uh number one if it's cold outside and you have a plastic shower curtain folded up in your trunk I just like to see you unfold it you know it's stuck right it's forty degrees and the second thing of his summer time has been really humid outside you pop the trunk they are can investigate for a dead body if you got a plastic shower curtain liner just thinks like heck you get the cloth shower curtain liners the hanging fold him up threw him in a suitcase what have you they do but amazing amount of different work for me I can take him on a wall with gaffer's tape if I like the people if I don't like the people dr duct tape um because it pulls the paint off and when we wake put it on the floor and like the floor up get something down there we can put a light through it's a very great tool but well actually put it before this so we're going to the same shot on a pro photo and then on a speed light with a shocker okay so we have our young lady over on this side wait take some questions before we absolutely we move over alright um nikon rick is wondering how would you measure a flash with the camera meter and a light meter thank you and that's that's also in the pdf uh you use a great card so instead of the meter at this end you simply put your camera right next to your flash so that the flashes illuminating that great card and so I would recommend you put it on the stand and you keep shooting that great card until you have one spike dead center of your history graham because then that great card is giving you back middle grade we've done it both ways and actually found that were within an inch maybe an inch and a half every single time so it's very very accurate so if you don't have a meter use that great card and go for the center I use one eighth power because when I have my string I now khun go up in power or down in power and I could go up in I s o which changes globally everything I can move it farther away etcetera and I started fifty millimeter zoom and the reason I started fifty millimeter zoom is with invariably every strobe I've tested with the exception of the nine hundred sb nine hundred seems like some will and some won't but everyone I've tested if I zoom out like pulling out eighty five millimetres you'll gain about two thirds stop because it focuses the light and if you pull it all the way back two twenty four you'll lose about two thirds or a full stop because it's spreading the light farther so you have all of these different that's a great question because that just went right past me you have all these different variations that you can use now you khun also lower the power by zooming the head back on those little tiny soft boxes that go on the front of these things you think would make any difference if your if your head was zoomed out all the way to eighty five or if it was back in twenty four it doesn't but if you zoom it out the eighty five and you put that little lumet quest on the front you get practically a full stop more that's pretty cool isn't it a full stop we only have seven stops I mean our world is two eight four five six eight eleven sixteen that's our world twenty two that's it some of you guys yeah I gotta f two okay good for you so extremes on those at both ends I also have one that goes to an f one hundred twenty eight so view camera lens so we have all of these variables to play with and that's what makes a speed light very a very powerful tool very powerful tools these are not toys half of that some of these things cost more than the big ones you know so it's a very powerful tool works really well I love these in the studio once I get outside the m e becomes so powerful that these are a pain in the butt for me so that's a question absolutely a lot of folks have that yeah a vintage designs mrs thanks for that camera meter history graham to measure the light thanks again done okay cool any cushions in the audience so far alright um and let's see moore how does the how does the measure changes at different zoom values back to that um I've found that almost like I said almost every one of them when you pull it all the way out you'll get two thirds of a stop more and if you go all the way back you'll lose about two thirds to a full stop uh I use the cannon flashes and they have that seventeen millimeter thing we if you pull the little diffuser out drop it down you can't zoom after that zoom has turned off you're automatically in seventeen that that'll kill about a stop and a half but it really spreads the light out but they're all about the same if you're talking about every little increments that's the little dicey because we don't have never measured that I've just gone full in back you mentioned the s p nine hundred which is the one I have why is that one day if I have found so many different variations with sb nine hundreds I can't tell you I've had some sb nine hundreds you zooming out to two hundred take the reading and it's practically the same as it was when is zoomed it fifty and and uh photographer had three of them the second when he put it down zoomed out the two hundred was a stopping a quarter more whether it was his units or not but I've found across the board that that it's inconsistent as faras as that