Hyper Focal Distance
Final section here is where my favorite sections, which is the hyper focal distance very complicated area people often have questions on. This is very important to the landscape photographer. So what is the hyper focal distance it is thief focusing distance to achieve the maximum depth of field? In short, it is a number. It is a number that is a distance from you where you are to focus it could be one foot, it could be ten feet, one hundred feet. It could be it's a number like that and it's, where we're supposed to focus the lands to have as much in focus as possible. Now the depth of field formula in general terms is about one third in front and two thirds behind the plane of focus. And so if I focus on something a little bit in front in a little bit more and back behind, that subject will also be in focus, depending on what aperture I choose. Now all of this, of course, is going very according to the lens, the focal length that I use, the aperture that I have said on it and the dista...
nce so these are the same things that affect your depth of field, all right? Those are the same three things that were going to see over and over again when we talk about depth of field and so, considering all this let's, take a look at the yard stick and we're going to get one third in front and two thirds in back. And this is a rough estimate. It's not exact. So let's focus on number ten and let's choose a fairly wide aperture, which gives us very shallow depth of field. What does that mean? That means, for instance, we might have one inch in front and two inches in back. That's what we mean by one third in front, two thirds and back. Now, if we just stopped down and get ourselves a little bit more depth of field, we might have two inches in front and four inches and back. All right? And then we can stop them all but for them, and we get a little bit more in front, but we get a bit more in back, all right? And we could take it all the way down to the smallest aperture opening that we have available. Bless. And we're getting the whole bunched up the field. And in this particular shot, we've decided, you know what? Those mountains that are way off in the distance we want those and focus as well, so that's infinity, the mistake a lot of photographers make. Is that they just point the camera at the mountains, and they either auto focus or manual focus on the mountains, and what happens when we do that is we lose all that depth of field behind the point that we're focusing on because remember, it extends forward and behind wherever it is that we're focusing on. We need to focus more towards the middle of what we want in focus, and now they don't get as much depth of field. What they should have done is move it back just a little bit, so the back and in their focus reaches those mountains, and the problem is, is that you don't see this in your viewfinder. Well, most people don't. I know if one camera that actually shows this in the viewfinder, which is kinda nice, but it's, not a nikon camera it's a fuji camera that actually shows you your depth of field in there, which is very nice, and so you need to be familiar with how this is going to work. If you are wanting to take the shot where you have the flower in the foreground and the mountains in the background and so illustrating the exact same idea, but from the side point of view, you can focus on the mountain with shallow depth of field flower is out of focus that's no good we can set all right f twenty two that gets us lots of depth of field will we have just wasted two thirds of our depth of field on the back side of the mountain there's nothing back here we want to focus we want it to be on the flower if you just focus on the flower we saw those examples earlier but when we're focusing just on things really close up we don't get my step the field in most cases most all cases there is a magic spot for you to focus right in between close up and far away that will allow you to extend the focus from the foreground to the background and that's the hyper focal point we're trying to figure out where is that point? And so when it's done correctly, subjects in the foreground are in focus. Subjects in the background are in focus a common technique for travel and landscape photography so it's something I like to do a lot. So all of these are examples of hyper focal distance where I'm really trying to make sure that the foreground subjects are in focus as well as the background subjects are in focus now it helps to have lenses that have good information that can help you out so many lenses and we're gonna talk more about this as we get into the lenses is the focusing scale on the lands and the hyper focal scale this little scaled out here which shows you how much is going to be in focus and I started in photography in the days of manual focus and back then they had beautiful scales on these lenses that had nice colored markings and nikon was really the best at it because it was really easy to take a twenty millimeter lands and set hyper focal and you know this is a good one this is this is a like a lads and this is a nice hyper focal scale good information and frankly these cheap lenses that don't have any information it's a photographic crime you know that is just terrible I don't want to use that because it doesn't give me any information so this is what a focusing scale would look like so it tells us where we're focused out now the better the quality lenses especially of yesterday in nikon still makes a number of manual focus lens is that they sell today that have beautiful piper focal depth of field scales on him. So now this scale is going to show me what's going to be in focus and how much is going to be in focus depending on what aperture I haven't said so right now I'm said it two meters let's focus on three meters and if we were to set f eleven I know everything from two to five meters would be in focus because that's where the focusing range is at f eleven right now. If we focus all the way out to infinity and I set f eleven. Well, I get everything from ten feet to infinity and focus, but I have wasted this information here. All right? If I wanted as much in focus as possible, I would look at my lands and I go. I can stop this down to f twenty two let's, line up infinity right here and now this is the far point of infinity, and it will reach all the way down to two meters and focus. So this is thehyperfix called the hyper focal distance in this imaginary scenario is five meters or fifteen feet, and that allows us to reach from here all the way up to infinity and focus. And so this is the hyper focal point. Now, let's, see how good you are at guessing what the hyper focal point iss with different lenses. All right, if we have a wide angle, twenty eight millimeter lands it's not super, super wide, it's just kind of, you know, simple wide lands, and we want infinity and focus, but we're senate f twenty two, so we're getting as much depth of field as we can on our twenty eight millimeter lands. Should we focus at one point five? Three meters or six meters think about how far away you're going to focus the lens so we'll just do an audience participation pull here and raise your hand if you think it is a one point five meters away we have two people be three meters away okay looks like everybody else just make sure anybody else for sea okay? So it's between a and b and the correct answer is aye so one point five meters allows you to get everything from seventy centimeters to infinity and focus now, just in case you're wondering how does he know that I went online have depth the field calculators they haven't you can download them to your phone and you can punch him in there and there's a few different parameters that you can type in but you can get this all figured out on a calculator there's an app for that. Okay all right before you download the app I'm going to quiz you on the rest of the things here so now we're going a little bit wider angle we got even more wide angle twenty millimeter lands f sixteen not all the way down but still pretty far down should we focus a half meter away one meter or two meters to get infinity and as much as possible in focus and who's going to go with a half a meter be a meter few answers there see two meters okay, the correct answer is b one meter so you're close I mean, this is a really tough quiz here, folks. I gotta admit you really tough quest all right? We're gonna do one more fourteen millimeter this is as wide as we get f twenty two that's a small as we get so we're getting a little much depth of field is possible twenty five fifty and one meter so let's go who wants a twenty five centimetres away? That's really close b fifty centimetres away and see one meter away everyone's going for c in the classroom here and the correct answer is b on lee fifty centimetres away which is about a foot and a half is where you'd be focused and you would get everything from nineteen centimeters to infinity with an extremely wide land stopped all the way down. All right, so here's the problem I can explain this all day but when you get out in the field and you got your shot of mount rainier lined up you're going to be saying okay, where do I focus? I need to focus I mean all this is theory and nice in the classroom and there has been a rule of thumb that I think is very inaccurate and I would like to see shoved out because it's not accurate and that is one third into the frame and so there's partly it's not clear and number two it doesn't make sense okay, so what is closest here? This is like what three four feet away and the mountain is about two miles away okay what's one third of two miles that's like appear okay, that doesn't make sense you're not gonna focus their um some people say well one third of the frame so it's this high so we'll go up one third well, you know that changes dramatically with how you compose your shot where your horizon linus and so one third in the frame is not a safe assumption I'm going to give you a much better one but we need to go back to the quiz and look at some of the results and look more carefully at it. So in this case we're twenty eight millimeters that have twenty two we focused at one point five meters and everything from seventy centimeters to infinity was in focus and there's a little bit of a math thing that's going on here take a look if we take the object that is closest to us and we double it we end up with something very close to this. Okay, so let's look at the next one so let's take what is the object closest to us it's forty seven centimeters we double it and it's very close to where we ended up focusing so the nearest thing and where we focused has a relationship of about doubling it now in this case, it's not exact. We take nineteen centimeters and we double it thirty eight it's, not fifty, but this is a rule of thumb, so we're allowed a little bit off. We weigh in here so we come back to this image here now we ask the question what's the closest thing in the frame and then we double it. So in this case, this near point down here is let's just call it three feet away. We would then focus six feet away, so line up the shot, figure out what is the closest thing in the frame that I want in focus this little piece of sand down here, salt, and then I'm going to double that distance from the image plane wherever the sensor is in the camera and that's where I'm going to focus and this is generally going to work out the only time it's not as if you tried to choose like a ladybug that's landed on the front of your lands if you've chosen something too close to the front of your labs and so what's the closest thing this rock in the foreground at the very bottom of the frame what's double the distance out there, maybe this other rock, and that is where we focus double whatever its nearest in the frame and so I work a lot with the twenty four millimeter lands and I thought, well, let's figure out the hyper focal distance for all the different apertures just to see what it looks like. So what? Two point eight the hyper focal distances all the way out at six meters and you get everything from three point four meters to infinity and focus and that's not a very good focusing because you don't get really that much and focus you stop the aperture down, you're gonna get much more now our little target area this is where we're focusing and then the blue line is the nearest thing that also happens to be in focus and so as we set at four, we get more depth of field and we can bring that focus a little bit closer and I just wanted to illustrate the different hyper focal distances because well, frankly, I have never seen this laid out like this. I wanted to see what it looked like with different apertures, and it shows you how much you're getting in focus and traditionally a landscape photographer is going to be shooting at eleven f sixteen or twenty two because that allows them to have subjects that are less than a meter from the camera in focus and in our most extreme case f twenty two we get everything from forty four centimeters which is just over a foot foot and a half all the way to infinity in focus now, something I will just geek out on for a moment is that these numbers depend on what you define is in focus, okay? And a lot of the numbers that I have pulled up here are standard practices for photographers, and the standard practices are actually standards that were established back in the thirties and forties, and we haven't changed, but the quality of our equipment has gone up. And so there are case is to be made for saying that that's, not the depth of field, we're going to get it's going to go from sixty for tow to infinity, and so it kind of depends a little bit on standard. So that's, when I alluded to the circle of confusion, you can change that, and it changes this a little bit. And so there are some focusing tables and scales that aren't quite there little too loose on standards, and so you'll have to test that yourself to see how well it works. And so I wanted to put together another hyper focal scale, and in this case, I wanted to compare different lenses all shot at f twenty two, all right, so if you want a lot of depth of field and this hyper focal distance, where would you need to focus with everything from a sixteen all the way up to an eight hundred millimeter lands? Now, clearly the wider angle, the more you're going to get in focus and so you can focus as closest forty centimeters and get everything from twenty centimeters to infinity and focus. And so when we talk about the hyper focal distance, were almost always referring to white angle lenses, it just is not very practical. Once you get into the standard lands or to a telephoto lens, we concede with fifty millimeter lands, we have to focus all the way out at four meters to get something and focus two meters to infinity would be in focus, and you can see how this scale really ramps up as we get into telephoto lenses and so telephoto and hyper focal, they generally don't go in the same sentence and let's get out there all the way with an eight hundred millimeter lands you were supposed to focus one kilometer away from the camera and you will get everything from a half kilometer to infinity and focus and so very ago, hopefully that doesn't confuse hopefully that helps you rather than hurts you in the world of paper focal distance fantastic, john well, we do have mariah who says thank you, john best description of hyper focal distance I have ever seen. I never understood what happened beyond that to that two thirds and beyond so awesome thank you do have a couple of quick questions the first one could you tell us again? Verify? Mueller had asked how would a focus go work on a zoom lenses this just for fixed funds is or just apply to zoom lenses as well. So back in the sixties and seventies they had these beautiful manual lenses that these nice scales that you could work this with, and then they started coming out with zoom lenses and they had to develop zooming scale so depending on where the zoom was set, you might have seen lenses that had all these zoom scales on him and you could then check where that depth of field is nowadays zoom lenses pretty much zip you got nothing that tells you that the field you know, let me just take a quick look at any of these lenses that have yeah, all of these zooms, they don't have depth of field scales on him at all anymore. And so that's just one of the downsides of using zoom lenses that because everything's gone elektronik and internal with the focusing, we don't have those scales anymore, and so this is where either the app or experience I'm going to develop an app called the experience athletics that's just going out and shooting thousands of photos under different scenarios with different lenses great a couple people are asking the people are asking about using your depth of field preview button and if that works with hyper focusing if you are able teo sort of see anything mohr yes yeah and so most of the cameras will have a depth of fuel preview but let me grab our camera over here and some cameras have ah programmable button but on this one there's a unlabeled button right here I can sometimes called the mystery but because there's several mystery buttons and actually on this one it's uh up above and so by pressing this it stops the aperture down to the working aperture and you can look in the viewfinder and you can see how much depth of field you're going to get now one of the nice things is that you can also put your camera in live you and do that you can put it really feels weird been talking about lenses all day and holding a camera rather than the land them like flowers hold every piece of technology and so yes depth of field preview will show that to you could be very very handy to help pre visualize what it's going to look like and that could be very handy using it in the viewfinder under bright light conditions as well when you can't see the viewfinder in the back