Lessons

Lesson Info

Background Isolation and Depth of Field

so we talked about isolating things based on brightness but going out when it's really bright out lot of contrast out in looking for what is the sun catching and saying what if we just show you that let the darker stuff go black or do the opposite what's in the shadows may we just want to show that and let the bright stuff go white we do that by changing exposure compensation which just means let's brighten her darken the exposure and taking another picture now let's look at another method I use for isolating a subject from its surroundings and that would be with depth of field depth of field describes how much of the scene is acceptable sharpness some people will say how much of the scene is in focus that's not quite right in that on ly the spot where you actually focus is in focus in anywhere other than that it's starting to get softer and softer it's just a matter of how soft is acceptable so it's just kind of a technical thing but I'll just say acceptable sharpness or is just how m...

uch of the images sharp so if I want to isolate something I could make everything else be out of focus and by doing so whatever sharp is what my eye is going to be drawn to hear I'm just at a winery and that's one of the vines that I'm focusing in on I just thought it was an interesting shape especially with the fall color behind it uh here I can get these in focus or at least I don't have the far one and focus or I can isolate and that is just by changing my aperture setting lower the number goes with the aperture the less stuff is going to be sharp the higher the number is the more stuff will be sharp but what you should realise is when you look through your viewfinder you're seeing the equal into what's known as wide open wide open is the lowest number that that thing can go to the aperture setting so when you look through your viewfinder that would be the equivalent to shooting with lowest number that your aperture scale goes to and it depends on the lens how low that number is on in expensive lenses that will probably be half four that's the lowest it'll go to when you get teo more expensive zoom lenses that will be up two point eight and if you buy prime lenses the kind that don't zoom at all that can go down to f one point four in that kind of thing um if you're not used to that scale you see if I have it this is the scale of f stops that let me open that I'll make every other number a different colors it's little easier to look at if you look at the way the numbers work with your f stops every other number you notice it's just doubling the number so you got f one f two four f ate f sixteen that kind of stuff but each time you go to the next setting here you are either doubling the amount of light coming in your camera or cutting the amount of light in half so what that means is he started out at f eleven and you decided for some reason needed to change and you wanted to go to f sixteen that's goingto let half assed much light into the lens of your camera so in orderto have the picture look justus bright you'll have to do an exposure that's twice as long because if you're using lame half assed much light come in to get the same amount of light total you need twice as long oven exposure so anyway these air the ranges of f stops you find on most lenses and in general if you want a limited depth of field if you want to have the background end up being soft you need to be on the lower range of these numbers the lower you khun go the easier it is to knock the background out of focus and that has do also with what lenses you buy a lenses that are relatively inexpensive will have the lowest number it'll go to is one of these two right here usually when you zoom the lens the lowest number it can go to will vary between these two as you get the longer range of the zoom where you're zooming things in closer and closer it will say that the lowest you can go to his five six as you goto wider and wider angle it'll say lois didn't go to his four it'll changes you zoom lens if you spend more on your lens it's a zoom lens then you can keep it a two point eight regardless of what the zoom lens is set to and just know the lower you can get this to go the easier it is to knock the background out of focus and that's why some people don't buy zoom lenses instead they buy ah prime lines where it doesn't zoom it all just got one number on it and they end up buying a one point four or you can also get a one point two of kind of in between here and that makes it much easier to knock the background out of focus so let's talk a bit about that you go back to where I was in my images here because of a few different things you need to know about when it comes to trying to knock the background out of focus we're tryingto isolate something using a shallow depth of field the first thing is the farther away the object is uh the harder it will be to knock the background out of focus if you want to not bet the background out of focus it's best to magnify the image the more you magnify the image the easier it is not the background out of focus so with a wide angle lens you need something really close to the lens put something of foot in front of the lens focus on it the background will start looking like it's out of focus but if you put that thing five feet away there'll be no way to get it out of focus because do you remember on a wide angle lens and a remember when I looked at the focus scale in here that told you how many feet away you're focused once you get up to the marking where should say five feet instead it's got an infinity symbol which means everything beyond that would be in focus as well so with a wide angle lens we need to get something really close to the camera lens in order to get anything in the background out of focus so if I'm trying to do it with a wide angle lens I need to move up within maybe a foot of it uh whatever the closest focusing my lens could go to my lens here can focus the less than a foot away so I could get something you know somebody's face maybe a foot away from the camera background I could get out of focus if I focus right on that thing that's close but otherwise I'm gonna have to move in closer to the subject and then I'm gonna have to take that aperture setting and I'm to lower it to the lowest setting it can go to and I'm going to start getting more limited depth of field so this is it see this is f sixteen this is a four watch this little area back here sixteen for now this particular lends the lowest I could go to us for because it was um or inexpensive lens and so in order to get anything more out of focus I need to move even closer because the closer the more you magnify it the less step the field you have in general and so if I'm at the lowest I can go already and I need even more out of focus magnify the image more get closer to the subject zoom lens mohr or anything like that it will be easier to get things out of focus question do you ever use the um dips of field for you yeah I'll talk about that too right now we're talking about limiting the depth of field in what I see through the viewfinder is what it looks like when it's wide open I mean lowest f stop number I can use and so most of time just looking in the viewfinder and seen ones to get not a focuses like it close to things is when we're trying to get everything in focus or get multiple things and focus then you'll see me using that so just know that the more you magnify things the closer you get things to the lens the easier it is to get them out of focus so here I am at cadillac ranch there's the ten cadillacs and I want the foreground to be out of focus well if I focus on the cars that really far away if I'm using a lens let's say a wide angle lens so I'm not sure what lens I used here but let's say it's not that wide it's probably a medium or a telephoto here but the stuff down below it is at least five feet away from the camera because I'm shooting from eye level and so below me it's at least five feet down there that is the background if I want the background out of focus why not get it closer to the camera get down on your belly and get that stuff really close to the lens because as you get close to the lens if I'm farc focused far away the stuff close to the lands is what's going to go out of focus if I'm focused far away so all I did was moved out moved down into my belly and people always laugh at me when I'm down on my belly they look at me really funny and all that kind of stuff but I'm getting a better photo than anybody standing on normal height so this compared to this did it again a different time when I visited uh cadillac ranch I've been there so many times I've probably been a cadillac ranch eight times or more I'd actually like going back to the exact same location over and over over again because the challenge is to create a new picture I haven't made before and if you go back the same time all the time you're challenged to come up with something better in different than we did before so hear again from a little bit up and then get really close to the lens by moving your lens down close to the ground and get more interesting foreground yes sometimes I go back same location and I give myself a limitation in this particular time when I went back I said I'm not going to shoot this from any less than about two hundred feet away and that was my limitation what could I do with that and then that was forced to figure out what the dio and it made it so if I can get better at shooting this one thing that I'm used to with those limitations and I get my brain around it I'll be better at shooting anything because I'll have I'll know how to think about that limitation here him in africa you know you can tell with the background since it's so out of focus that this was a little bit more of a telephoto lens let's see what it wass this was a five hundred millimeter I'm at f four which is I believe the lowest that it can go to and I'm focused on the lion and those air somebody buddies station a workshop in africa and those are some of the participants and this is what I got I wanted to show how close people are in all that s o let's extend that and here I have a serious alliance noticed the background the background you can't do that with a wide angle lens remember how you get more than five feet away and everything's in focus so instead of using o a wide lens that can cover everything what I did is I grabbed a long lens that could only show me a small portion of the image like only show me one lion it was a five hundred millimeter lens and I got one lie in it then I pan the lens over to the right click pan and lens over to the right click and I kept doing that until I got the entire scene and I stitched it as a panorama in that allowed me to get the entire scene that was there yet still get a soft background that I wouldn't be able to get if I used a lens that wasn't quite as long because the longer the lenses the more the background goes out of focus here's another one if you look at this one you see all the lions sitting there in the background is going semi soft in many areas now if I shoot the same general scene was just this is a stitch panorama if I shoot it with just one lens look at the difference it's not the same scene but it's a similar scene look at how sharp the background is compared to this you see the difference and by getting it where the background is soft then those very detailed trees in the background your eye isn't drawn to him quite a cz much sure you glance on him but there's not enough detail to keep your interest that long so your eye goes toward sharp whereas with this one there's a lot more detail in those trees so if my eye flicks up to one of the trees and michael cool what's this and just keep looking through the trees because there's enough detail to hold my attention whereas if I get him soft enough then that's not going to be the case so let me show you the actual images that I used to capture this with I have to switch over the light room to do that and I believe I have him here so this is what I'm often doing when I'm in a place like africa I have a really long lens on this is a lens I rented it is a five hundred millimeter lens only see if I had a telecom murder on it or not ah no I didn't okay sometimes I put that little one point for thing that makes my lens pull even it makes it act like a longer lens and I didn't have it on in this case but I sit here I have it pointed right there I have it all in the frame and I'm just waiting for one of you look at me because they're looking everywhere else and I'm going click every once in a while because I don't know if it's going to get any better if they're going to get up and start walking away so every once in a while somebody look somewhere else click I do it and then this guy right here turns his head to look over at me on lee for a millisecond and click I got him look great but this shot all by itself it doesn't really show me the whole environment so what I do is after I get that shot on the back of my camera is a button on a cannon it looks like a nascar six on a nikon I think it has some letters next to it like but would it be e l or something like that on on it but it's auto exposure lock and what that means is locked my exposure so if I point my camera something bright don't compensate for that if I point my camera something dark don't compensate for it used the exposure that you have right here when I had appointed this spot so I press this little button on the back of my camera one of the cameras pointed over here or not but on my camera it is ah button over here I'll leave that sitting there that looks like an ass tricks and if I press it it means lock my exposure until I press this button the second time and so therefore I know if I do a panorama across this area they're all going to be the same brightness it's not going to be varying as I hit other other things so let's look at some of the other images so now and also I click my lens over to manual focus otherwise it would start focusing when I pointed over here on the far things so click it over to manual focus hit that little button on the back of the camera to lock the exposure and therefore focus stays the same in the exposure stays the same that makes sense and then I just start shooting around now these don't have previews loaded this is light room and it doesn't have high res previous except for the very first shot so these will look soft but if it had the high res images attached on the hard drive they would render in the and this would look sharp for the lions are but anyway I'm panning across like this and I do the next row like above it ok good up there really high in the trees that kind of stuff and I took all those shots in stitching together in order to produce something like this so I want a wide view but I want a limited depth of field where the background goes soft when I have a lens that can capture the entire frame if I look on the little focus scale by the time I focus on the lions I'm either at infinity or I'm really close to infinity where it means that we're really close to getting absolutely everything behind it and focus anyway and so it's not going to be all that soft it's gonna look like this in order to get that out of focus background I say let's grab a longer lens because longer lenses can't give me such deep sharp areas and so I grabbed that longer lens and I make it wider by stitching a panorama together and I was just lucky none of them got up now you know they didn't mess up that kind of stuff so that's the difference you want a perfect um when you're panning yeah are you you're on a tripod ru does that do you turn the camera like this or do you move the camera usually turned the camera ok but it depends on what it is I'm shooting I just shot the other day in a railroad um roundhouse with the rail cars come in and they turn him and then send it out on a different track and actually walked in an arc around that I wanted it tio have a certain wide look to the shot but most of time I'm just rotating the camera yeah cool thank you sure so all we've talked about isolating things in two different ways one is isolating it with brightness bye on lee letting the bright areas really have detail on lee letting the darker is have detail that's mainly when what's really bright outside it's more like noonday sun kind of time when you have that huge difference between bright and dark no if it was overcast or if it was some other condition where the brightness doesn't vary that much then I wouldn't be able to isolate in that way so I might instead decide to isolate with shallow depth of field longer the lens the main thing you need with to do this is two things you need your aperture setting to be low and then you need to magnify the picture you can magnify the picture in two ways one is moved closer to it if you have a wide angle lens that's the only choice you really have to magnify move really close to your subject otherwise if you have a long lens just zoom your lens to a much longer setting and then your magnifying the image it's as you magnify the image and get a low number for your f stop that you will start getting the backgrounds to go out of focus and it's more difficult with a wide lens than it is with a telephoto if you have a wide lens get something really close to the lens then others concepts I use when I'm in the field on the way I think about them is sometimes I try to connect a far in a near object because there's some sort of relationship between the two there's a person in the distance that's a firefighter and then there's a fire that's closer to the camera and I don't want the fire fire to feel like he's really far away or not even in the frame I want to make them feel like they're really close to each other even though they might not actually be and I think I showed you this image before were a long lens compresses space it makes far things in near things feel like they're at a similar distance whereas a wide angle lens makes things that exaggerates the distance between near and far objects so when it comes to that if I want to set up an image like this one then I got to be really careful it's can't just press the button and expected to work because when you grab a longer lens longer lenses is going to do that compression of space you also get less step the field you know less of a depth that's acceptably sharp so that means we got to start being careful with our aperture setting so in this case what I did is I backed up a ce faras I could go the farthest aiken goes where the freeway is right behind me if I keep going on the stand in the middle of the freeway lots of semi trucks going by I found whatever lens I could zoom to keep this gate in there this is actually a panorama of two shots to get this but if I could have backed up so I stepped onto the highway I could've gotten the whole thing in one shot then I get the lens and I say well which lenses it that's long enough that will keep this gate in there and I experimented the lens until I get that then in order to get both the gate and the cars and focus I'll say in focus but I mean sharp because there's only really one point and focus on what I need to do is realize that wherever I focus there's going to be one third of the area in front of the focus that will be a sharp in two thirds behind it so there's there's more behind that's going to be focused less in front so that means I put my focus on this front object get it sharply and focus I remember where that isthe with my fingers on the little zoom thing I heard that the zoom thing the focus ring and then I focus on them far thing and so I can see how far is that physically that I need to move my fingers to go between the two and then what I really want to do is focus a third of the way between those so a third of the way back so I would kind of pick an area about here to focus and sometimes I could do that just visually just k okay yeah that looks about right but what happens is the cheaper the lens you have the harder it is to judge where you're focused the reason for it is you know how the lowest number that your aperture setting window to the cheaper the lens but the higher that number will be it will be f four instead of f to eight well it makes it so more stuff look sharp to begin with through your viewfinder that's a little harder to tell exactly what's in focus as you get a more expensive lens where when you're looking through the viewfinder your f stop numbers they're going to be in lower itself to point eight it's f one point for your scene in the viewfinder less and less stuff and focus so it's easy to tell where that focus point iss is you get to cheaper and cheaper lenses it makes it so it's harder and harder to tell exactly where you're in focus there's more and more stuff looking sharp it's hard to tell exactly where the focus point is but if I could make it a third away in there now in most lenses if you just take your focus scale and you focus on the nearest item look on your little scale it's here focus on the farthest item and look on your little focus scale and then move this halfway in between you'll be pretty good because this scale is not linear it's not evenly distributed as faras the distances go and if you're about halfway physically between the two points it's actually more like a third in actual space it's kind of weird just the numbers aren't equally spaced it doesn't say five then tanner than fifteen evenly er and so just do it focus on the near thing focus on the far thing and then set this right in in the middle and that's one way of working then we have to choose an aperture setting we have to just set our aft stop number high enough that both that near thing in the far thing look sharp and we gotta pick one I'd rather not pick it off the top of my head because I could easily get it wrong and if I do then it's not all gonna be sharp so what I'll do is I'll guess from experience let's say bring it up to f sixteen just to give me more than what I had then on my camera put mine in f sixteen I have a button on my camera it's right next to the lens it's not over here is the one for releasing the lens but on the opposite side at least on my cannon is another bun not all cameras have this if you have a very inexpensive camera might not have it but if you have on average camera it'll probably have it it's the depth of field preview but if I put my finger on it and I press it my lens will change and if I look through the viewfinder when I press it the viewfinder gets dark I still see the scene but it's darker what is doing is the aperture setting that you're setting is actually an opening in your lens like these looks like this inside your camera and in fact if you look in the lens like this when you press that button if you set the f stop numbers high as they can go and you press that button you can see it in there if you get enough light in there but it closes down this or not quite perfectly open would be wide open would be the lighting is much light in a cz you can and as you what's known a stop down your lens it's getting smaller and smaller these would be the equipment the higher and higher f stop numbers and when you press that button instead of showing your viewfinder with the lens wide open which is bright is it khun b which is usually what you want to see it stops it down and what it actually does is previews how much of your image is going to be sharp the problem with it is your view finder goes dark and your brain goes well this doesn't look right and you think it's not very useful because it's just a dark looking scene but what you can do is this I've already picked my focus point it's one third back from the front most area I looked through the viewfinder and I stare at the farthest away thing in my view finder I press the button the viewfinder go stark I let go press the button let go and all I'm doing one staring at that faraway item this same did it go sharp did it become sharp even though it got dark I don't care on looking at did it becomes sharp then I look at the nearest thing that I'm trying to keep sharp and I press the button on and off and ask myself did it become sharp if it didn't need to goto a higher eh stop number crank it up higher and tested again and that's how I'm going to figure out I need to be focused at the right spot one third of the way into the depth of photo and I need to just guessing my off stop to begin with in afterwards hit the depth of field preview and see if those things pop into focus weird because if you find her goes dark but it's overly useful once I have that then I know I'm set up right and now I take a picture I look at the end result and just ask myself is a too bright or dark if it's too bright or dark exposure compensation is what I go to go into the plus side if you need a brighter going to the minus side if you need a darker in find the setting you need so what did we do we gotta set up like this we picked the lens we needed to fit what we want get the compression we wanted and we focused one third of the way in we guessed that are after setting hit depth of field preview to see if that worked out if it didn't we upped the number even hire guest again with our depth of field previously if those near and far areas are looking sharp with it once they were looking sharp then we just took a picture look at the end result now is it too bright or dark if so exposure compensation into the plus side if you need a brighter into the minus side if you need it darker than you could get your shot takes a little bit of practice but once you get used to it you can get these kinds of shots if for some reason I'm unable to get both the cars in the gate sharpe just the highest number it goes to still doesn't get it sharp then I would take two photos focus with one just a little bit closer to the back of the photo you know distance wise click then switch my focus a little bit closer to the front and take another photo so I'll end up with two photographs where one has the cars in the back and focus one have the cars in the front and foe lois just by moving my focus well the little spit in each direction and then I can combine those two shots and photoshopped there's a feature and photo shop that would do it for me it's almost automatic uh so if I can't get it I'll take two shots questions about that you've been actually answering them we did have a question that which you often do but phoenix west just asked what software using to stitch the images together photoshopped and I was almost like are you kidding I just photoshopped there are other pieces off where you can use but it's just what I use the most great thank yu gi in the chat room just chimed in and said this is so awesome I cannot believe I never knew these tricks yeah this is what I wish people told me when I started taking the pictures instead they told me all sorts of other weird stuff I'd ask him what len should I get they tell me they said get one hundred millimeter macro I bought it it's sat in my bag for two years and then I sold it because it wasn't for me what they didn't ask is what do you shoot what do you like to shoot what do you complain about when you're shooting those tell you what you need not just what somebody tells you to get