in this Article I want to talk for a few minutes about getting a correct exposure now let's back up just a second and make sure we know what we're talking about when we're talking about an exposure an exposure is basically taking a picture and the settings that you're using to take that picture so that it looks the way you want and that's what a correct exposure is a picture that you've taken that looks the way you want so it doesn't necessarily have to look the same as what your eyes are seeing for it to be correct to you but in this case we are going to use that as an example based on what my eyes are seeing I'm going to set an exposure of a scene and just kind of walk you through the options you have to change to create a correct exposure and things to watch out for as you do that so let's just real quick I'm in scene intelligent Auto I'm on the green a we're just gonna stay here for just a second I'm gonna press the live view button and here is the scene we're looking at we have some flowers and for those of you who have watched my other Articles you know right now I'm sitting under this big skylight.
it's an overcast day so I have nice diffused light coming in these this jar of flowers is at the edge of that skylight and beyond that it starts to get pretty shadowy fairly quickly you can see there's a ruler and there's something white back there we're gonna be able to see those things in a moment but here's what the camera judges to be a correct exposure of this image and it's pretty close but you know you the camera doesn't always decide what's best and in this case to talk about all of our options that we have to change I want to switch to manual and so that's what I'm gonna do now I'm gonna rotate the dial to M and you should follow along feel free to follow along I think this is going to be worth a lot more worth your time if you have your camera in hand and it doesn't matter if you have a Canon ti or a Nikon the the general settings that we are talking about are identical for all of these cameras so here I am in manual mode and very nicely across the top now I have the three options that I want to talk about when you're setting an exposure your first is your shutter speed that is the length of time that your shutter remains open when you take a picture right now it is set on one five hundred of the second because last time I was taking pictures that's what I had it set on and it remembers that and it keeps that there until you change it next I have aperture I'm just no press Q and high like that aperture is the opening the size of the opening of the lens it's expressed in a fraction we're not going to go in details to talk about that right now but I'll just say that the smaller the number the larger your opening lenses generally go from somewhere around depending on how much you pay one point to one point four all the way up to twenty to thirty six in that general range the F one point for F f those are very large openings almost as wide as the lens glass itself on the other end of the spectrum the f- f- for you to insert a pin through that's your range F five point six is you know kind of a medium over again expressed in fractions and finally your final option here is your ISO the sensitivity of the sensor now I know that's not great it's not very explanatory since I'm saying two words and trying to use both of those in the same definition but the the larger the number the more sensitive that sensor is that little piece of electronic equipment in your camera to the light coming in and it's a fact it's a doubling factor so at ISO at ISO it has twice as sensitive as it is at ISO at it's twice as sensitive as it is as it is as I'm gonna stop stuttering over my words there and let's just go back to our main screen so let's press life.you now and it's showing us this is one of the reasons why I really think life view is a great learning tool I've said that in other Articles that's showing us the exposure we would get with these current settings the shutter speed across the bottom five hundredths of a second our aperture . and our ISO of if we have pressed the shutter you can see that the camera helpfully says this is where I think your exposure is relative to a correct one correct one should be right there in the middle what the camera thinks is a correct one and again remember what the camera thinks is a correct one and what you want is a correct one are not always the same often they're very similar when you're just trying to take regular pictures but they're not always the same and I don't know if you notice but it didn't move a little bit based on the amount of light coming in through the skylight whether or not it's bright brightening the scene or darkening the scene so let's start to adjust our values of these settings to get a more correct exposure first thing I'm gonna do the shutter speed is already selected one five hundredth of a second is pretty fast I can go a lot slower than that before I run into any kind of negative effects do you know what those negative effects might be did anybody out there say motion blur now that is correct in this situation the camera is sitting still it's taking a picture of very still life nothing is moving so you could go to shutter speeds very very slow so it's multiple seconds and there wouldn't necessarily be any negative impact on your image and that would still give you a correct exposure let's do that disre fun let's go all the way down and take a picture one second long I dialed test one now my image of course is really overexposed I'm going to go to that makes the sensor as less sensitive as possible and now by holding down the AV button I can dial the aperture way up and notice is the maximum for this lens and the camera is now saying that I am over exposing slightly from what believes to be a correct image but this is actually very close to the image that I want to create here and I'm gonna go ahead and press the shutter button it's going to take a picture it took one second to take that picture let's go and put that on the screen for a second and get rid of all of the info but you can see one second f- ISO and there's my image and everything is fine we should be able to zoom in on those flowers and they are a little bit brighter than I would like but everything is crisp and the image is just fine we should also notice that the plant in the background although dark is in focus we'll talk about that in just a second more now that was the example of going that but what if I was taking pictures what if I was holding the camera or if I was taking pictures of people moving well those are two different things so let's say first if I was holding the camera and taking a picture of this flower the one thing that you want to watch out for is shutter speed slow enough that you won't be able to hold the camera steady during them if I picked up this camera and held it for one second the image would be very very blurry the general rule of thumb is that your shutter speed should be a bit higher than your focal length right now I'm shooting with a millimeter lens my shutter speed should always be above the one time that you can break that rule and you're holding the camera is when you have a lens that has is then you can go a little bit slower but now let's say you're taking pictures of something that's moving somebody that's moving your kid toddler a dog running in the backyard now you're talking about shutter speeds that you want to be up around th of a second th of a second that's a pretty good safe shutter speed for movement unless we're talking about things that are moving very fast or you could go a little slower things are moving a little bit slower in this case you can see that my image is now very very dark so what I'm gonna do is I'm gonna roll my aperture increase my aperture of good bitte I'll go two to eight pretty close and now I can increase my ISO sensitivity to and those flowers in the foreground are a little bit brighter than I want I'm gonna go back down to for ISO and now you can see that my exposure is identical virtually identical and you can see that little exposure meter at the bottom virtually identical to the exposure I shot a minute ago that was a one second in f- but notice there are other differences now let me go ahead and take this picture and press play back here it is so exposure wise brightness it is very very similar however that plant in the background now is very soft and not in focus because I was shooting at such a smaller aperture so aperture increases and decreases the size of your lens opening and that allows an various amounts of light depending on the size of the opening but it also impacts your depth of field how in focus things are so how I approach each situation as I say well what kind of aperture do I want for this now I said it accordingly then I figure out the shutter speed I need and set that accordingly and then if I need to adjust my ISO to get the shutter speed where I want to be then I'll do that so that's usually my approach start with the aperture and an easy way to do this is to shoot on AV mode you set your aperture where you want the camera will set the shutter speed and you still have to shut your you set your ISO based on that you could also go to auto ISO if you want I'm not a big fan of auto ISO it makes this is again letting the camera have a little bit more control and the more control you let the camera have the more likely it is going to be to make a bad decision it's kind of a bummer we do have these really expensive really nice cameras but they they're just not as smart as us after a little bit of learning and understanding these different how these different settings affect our image quality so this was just a really quick simple look at changing those values talking a little bit about exposure I'm gonna come back with more Articles that talk in depth I'd like to have a series of kind of recipes but really it all depends on what you see and the factors of fast enough to avoid motion blur fast enough to avoid handshake the the aperture that you want for the scene whether or not you want to kind of separate somebody from the background or it's a Vista and you want to get all of it and focus and you're gonna be shooting at those really high numbers which is really small opening and then the ISO and the one thing you want to watch out for your ISO with your kind of entry-level DSLRs is still around ISO above that we start to get quite noisy and so if you can keep below that number and the lower the better usually then you're going to have a better a cleaner image but if you need to go higher to keep that shutter speed from getting blurry or getting long enough that your image is blurry then you're gonna want to do that because a slightly noisy non blurry photo is better than a blurry photo that's not noisy unless you're going for artsy blurry so I hope this was helpful if you have any questions about it leave a comment down below or find me over on the Facebook page I do appreciate you watching as I said more Articles of this sort coming soon and I do try to keep them as short as possible but and we're covering topics that are fairly we and I want to give them the time that they deserve thanks for watching.
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