Lessons

Lesson Info

Intro to Manual and TTL Flash Modes

we said this over and over again flash exposure is flash output that's how it's affected and then your ambient light is shutter speed okay so here is where I'm going to get into the difference between tt on manual with speed lights and figuring out which is appropriate for you so I wanted to make a note that tt l is my short term for either e t t l or detail that's just different names depending on different systems so don't think that way is she talking about something that's different for me no it fundamentally all works the same there are a little bit of a difference but everything we're talking about it's going to apply the same concepts all right so with a speed light you have manual exposure and tt l here is the difference for manual exposure when I set the ratio of the power output on the back of the flash it stays the same and gives me the exact same amount of light no matter what so if I say one one twenty eighth power that's actually the lowest amount of flash output that I c...

ould get on manual I put on one one twentieth every time I flash it's one one twenties and we'll just stay there until I change on my trigger or the back of the flash it's set manually and it sticks there the values that you have are basically going ahead and dropping by stop so you've got full power one half one fourth one sixteen one third to one fifty four one twenty that's what you'll see on the back of your camera where in the back of your flash when you're trying to set manual output if you have one of those wireless triggers systems if you have that you can set this output from the trigger still it's not like it's just on the flash itself you can set it from a trigger all right so you got that so far eso it's controlled infractions of full power this is what you will see on your flat the m symbol and the one over whatever whatever power you chose so just like yesterday you know on the back of my studio strobe had numbers um it has I believe that one's four through ten in and of themselves they don't really mean anything to you so yes you could do calculations if you want to look it up it's not practical it's not useful it's the same thing like one one twenty eighth I it doesn't mean anything of how bright you're going to be lit it's just the amount of light it spitting out how close I am to you what modifier I have on changes how much light actually hits you so the exact same thing as yesterday when I wanted to make sure that the flash exposure was correct I used a meter on my subject and then varied the output of that strobe to get the exposure correct it's the exact same thing when you have your flash on manual you would do a test with that meter and if you were ambient light you're ambi exposure was at three point five I want to test and make sure that this right here is also three point five and in some pictures if I'm really far away with a huge modifier in front and I'm triggering on somebody maybe ten fifteen feet away on full power it might read three five and then if I change a different modifier and I come close maybe at one sixty fourth it's three five on you like those numbers don't intrinsically mean anything they're just amount of water in the bucket and we talked about that yesterday so my amount of water in the bucket if I have a full bucket back here and I throw it still might not quite reach you guys but if I've got a little itty bitty bucket you might just get justus wet if I'm standing right next to you so there's all these different factors that come into play so when you're looking on the back of your camera looking on the back of your flash and you're seeing all of these different ratios they don't really mean anything but how much water is in the bucket that I'm throwing so that is manual let's take a look at a couple other things here all right teo means you tell the camera you told you told a flash on the camera together listen I've got the ambien exposure I'm taking care of that would I want you to do is help me figure out how much late to spit out how much water to throw to get the correct exposure on my subject so I am letting the flash and camera talk to each other to decide how much water how much light to spit out for each photo and without me making any changes let's say that I on my camera I leave teeth seal exposure compensation zero which just means give me what you think is correct exposure that's that's all that means zero tell me what you think is right if I'm shooting my subject from let's say ten feet away it will spit out one amount of light one amount of water and if I don't change a thing I don't touch anything on my flash and I back up and I'm all the way over here it's going to give me a different amount of like because it's still trying to give you the correct exposure even though I've changed my distance here is what happens if I'm shooting in manual and I'm just going to the bucket of water thing again okay so if I'm shooting on manual and I'm here and I throw my bucket of water you get a certain amount of wet and I back up way over here and I saw the bucket of water you're going to be significantly dimmer significantly dryer because it's on ly throwing that same amount of water on manual so unless I change it based on where I am where I move your exposure will change from the flash where as we teach yell it knows here I want her to be a certain amount of wet a certain amount of illuminated it'll spit out one amount of lighter water and then without me changing anything it knows she wants the same amount of wetness over here throw more water to reach her further away so those are the differences between the two t ell is foryou event shooters for sure because if you're moving around and persons dancing every step they moved from you would be a completely different exposure especially if you have the first one set for sydney kambara you especially if I have for detail my first exposure set right here this is where I determine aren't sorry for manual I determined my manual flash exposure for this distance at this distance if I back up to hear she is a quarter as bright because of our inverse square law doubled the distance I quartered the power that is going to be completely impractical for any type of event photography or how about this okay let's pretend I have a white wall over here I don't but let's pretend that I d'oh okay can I bring you over here eh so I'm the camera she's my subject I turn and I point the flash at that wall okay so what I do is I figure out once the light bounces from the wall to her is at the correct exposure and I can go ahead and meter that and give it a test if we take two steps this way if we move this far we've just about doubled the distance now because I've taken a half distance further and she has so it has to travel that much for it's just you can't you can't bounce light you can't work with moving subjects so if you were an event photographer or where you have subjects moving maybe like little kids running around well that's what happens when I shoot kids they run around ever I'm really bad at photo I think it's maybe you have more control than I do but in general for events when your subject is moving in you're moving teacher I was going to be the way to go okay what are the downsides cause ttcl sounds awesome you can go rest yes okay so what are the downsides of tio t l l is taken control away from you you're leaving something up to chance and so you're saying flash camera talk to each other I want you to make some decisions here some common things that happened where your flash gets messed up let's say is there something metallic lying around you guys can bring me I don't just something randomly metallic um let's say that I am photographing you I've got my flashing uh off camera over here and I've got it set on tt l exposure okay and as I'm illuminating you the flash hit something medal right here and it sees a reflective surface and it actually thinks that's what I'm taking a picture of so we'd seize that medal it's really really bright that'll work perfect I don't know we'll say ignore this reflector you can hold it right here for me thank you so let's say that a metal table you know like one of those uh stainless steel cooking tables all right so the flash hits that and it goes well that's super bright and it will put out almost no light at all but I was trying to turn to letyou it doesn't it doesn't know that it doesn't exactly know what I'm pointed that so the flash might see that and give me the wrong exposure another thing that might happen is if you are at night all right and it's you again you have a flash off camera and you're at a reception at dark and I'm photographing and the subjects are pretty far away from me it might just read the black abyss and just full power nonstop because it just says well in this scene is so dark I'm kicking light out I'm not seeing anything as bright as I think it should be and it just over exposes I got that it's hon photographing people that are further away late at night because it just sees black this and it's like well I was trying to let this whole scene but it won't work so those air instances when it's not so smart you get stephen I don't make you stand there with that um so there are certainly downsides and there are times when you have to like in your head go okay so what is going on maybe you're like why is it underexposed oh there's a metal thing in the front or a bright white thing that it thinks I'm tryingto light they're insisting instances like that so teo is totally fine to use if you know when it'll mess up and how to outsmart it which I think is kind of like aperture priority sometimes aperture priority for exposure might just be easier but you got to know when it won't work manual is great when you have control because you're going to get exactly what you want you just like you take her studio shows you can meet her it to make it perfect and so that is four great for portrait ce and group shots another place where tt l messes up is if somebody is wearing all white and all black which maybe wedding right if you have a group of guys all wearing black how your camera and flash works is you guys have probably heard a little bit about exposure is aiming for like eighteen percent gray what that means is if it sees all black suits and it is dark outside they have little little heads right then compared the whole scene so it will probably and titi I'll give me way too much like because it reads that there is so much black there it thinks that's trying to get it up to a grey oh and I'll have a heavily overexposed picture or similarly a bride in a white dress against a wall it reads white and it won't put out enough flash so how do you outsmart it if you are shooting t teel how you outsmart it is the same way basically that you outsmart africa priority for africa priority right when you're shooting I'm not talking anything about flash right I'm talking about district cameras exposure when you're taking a picture and you're like wow it's just consistently too dark you use something called exposure compensation and so what you can do is you can say okay camera whatever you're looking at you're like a stop under I don't know why but at a stop light in and breaking it up with your flash when you're on t ell you have the exact same thing except for it's called flash compensation that feels the only difference so you can say men with photographing these groups of guys in the black suits against a black background I don't know why the flash is kicking out way too much light I can tell it minus two stops through two stops less than you're kicking out or the same thing is if I am doing a portrait I'm lighting you you're lit by the sun on one side of your face I don't want to have zero compensation and light the entire satellite shadow side because then it's totally flat and I just killed the lighting all I want is just like a kick of light into the shadows I can use my flash compensation to say you know what give me minus one stop I want to fill in the shadows so that they're not dark black but I don't want to completely flatten them out so that's what you're working with exposure manual you're controlling absolutely everything to saying spit out a certain amount of light or water but as everything moves distances you had to make a lot of changes we're just really impractical for things that are moving with ttcl it's helping you out and it's guessing but you've gotta outsmart it and know when to add flash compensation toe add more light or to take it away and to know what's going to screw it up and it may be in those instances switch over to manual just so you can outsmart it for those cases so that is my and of one more slide that is my overall talk about how those two are different so tco basically it determines what it thinks is the correct flash exposure and that is that zero compensation so if your flash compensations zero here to think flash tell me what this is supposed to look like coarse like I said it doesn't always know um and the flash compensation is usually all the way down or it depends on your system all the way down to minus three or all the way up to plus three on some systems it only goes up plus two or minus two depends on what you have this is an example on nikon where you could set the flash compensation in the camera other ones like on the back of this trigger here you can see that I have the flash compensation set to minus one point seven which is minus one and two thirds stops and you can see over there the thing that's circled is on the back of your flash where it would show your exposure compensation are your flash compensation which reads evey which means exposure value so when you see evey just think flash compensation am I going so here it's plus one and a third stop and you'll see t t l or some some types inversion that you teal I teo teo that's what this will look like