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Focal Length Rule of Thumb

Lesson 7 from: Nikon Lenses: The Complete Guide

John Greengo

Focal Length Rule of Thumb

Lesson 7 from: Nikon Lenses: The Complete Guide

John Greengo

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Lesson Info

7. Focal Length Rule of Thumb

Next Lesson: Field of View


Class Trailer



Nikon Lens Class Introduction


Nikon Lens Basics


Focal Length: Angle of View


Focal Length: Normal Lenses


Focal Length: Wide Angle Lenses


Focal Length: Telephoto Lens


Focal Length Rule of Thumb


Field of View


Aperture Basics


Equivalent Aperture


Depth of Field


Maximum Sharpness




Hyper Focal Distance


Nikon Mount Systems


Nikon Cine Lenses


Nikon Lens Design


Focusing and Autofocus with Nikon Lenses


Nikon Lens Vibration Reduction


Image Quality


Aperture Control and General Info


Nikon Standard Zoom Lenses


Nikon Super Zoom Lenses


Nikon Wide Angle Lenses


Nikon Telephoto Zoom Lenses


3rd Party Zooms Overview


3rd Party Zooms: Sigma


3rd Party Zooms: Tamron


3rd Party Zooms: Tokina




Nikon Prime Lens: Normal


Nikon Prime Lens: Wide Angle


Nikon Prime Lens: Ultra-Wide


Nikon Prime Lens: Short Telephoto


Nikon Prime Lens: Medium Telephoto


Nikon Prime Lens: Super Telephoto


3rd Party Primes: Sigma


3rd Party Primes: Zeiss


3rd Party Primes: Samyang


Lens Accessories: Filters


Lens Accessories: Lens Hood


Lens Accessories: Tripod Mount


Lens Accessories: Extension Tubes


Lens Accessories: Teleconverters


Macro Photography


Nikon Micro Lens Selection


Fisheye Lenses


Tilt Shift Photography Overview


Tilt Shift Lenses


Building a Nikon System


Making a Choice: Nikon Portrait Lenses


Making a Choice: Nikon Sport Lenses


Making a Choice: Nikon Landscape Lenses


Nikon Lens Systems


Lens Maintenance


Buying and Selling Lenses


Final Q&A


What's in the Frame


Lesson Info

Focal Length Rule of Thumb

So we've taken a look at all of the lens is now one of the things that I always like to be able to do is to be able to try toe just look at a scene and go what lens don't need I don't want to pull out every lands and try it on see if it works I just want to look at it and go yeah that's a hundred millimeter lands and so one of the ways that you could do this is by having shortcuts rules of thumb and so in studio audience put your put your notes down we need your hands for this and so if you guys want to see what a fifty millimeter lenses is hold your hands out like this and bend your elbow so they're nice and comfortable like that now your thumbs are not together they're probably need to have about four to six inches apart and if you want to close one eye that's about a fifty millimeter lands as you look through there okay you ever seen a very cheesy movie director do this lower you go looking for your close up here all right so that's about a fifty millimeter lands now I don't have an...

ything really cool to call the thirty five millimeter lands other than just a little bit wider okay just maybe a foot between your thumbs something like that and you contest this out at home yourself with your own lenses and so forth. Now twenty four you've got to go wider. And so if you put your hands on your elbows like this and gives a thumbs up on either side now what you see between your thumbs is about what you would see with a twenty for moments so I could get so okay, I'm going to predict for the five of you there that I could be right here with a twenty four millimeter lands. Okay, so remember where I'm here and I'm going to grab a lands and this is the fourteen to twenty four I will put it at twenty four, and I'm just gonna walk closer until okay, I'm cutting you off right there. So right here now, how close the might of my spot? Pretty close. Close enough for a rule of thumb, right? Okay, so that's the well, for now, with the sixteen. Not quite as exciting is kind of everything you can see with one eye e kind of eliminate that way, way, way edge, you know, one eye that's what you're going to see with the sixteen. All right, next one hundred millimeter from the pinky thumb to pinky. Do this with your hand, hold your hand out about us far away from me as you can and when you see from side to side is pretty close to what you're going to get with a two hundred millimeter lands and so if I wanted to shoot our creative live logo here on the wall I would probably need to be right about here to get it full frame so I'd know if I oh you know I don't want the whole wall I just want the logo two hundred millimeter let's all right so the next one four finger wide so pretend you want a little bird to land on your finger hold it all the way out okay now that's what I do have to mention on this is that how do I know how big your fingers well how do I know how long your armies my guess and I've been told that different people have different body part sizes but if you have a smaller finger you probably have a shorter arms and sew it I don't know it's going to be a little off it's a rule of thumb it doesn't mean it's exact and so what you see from side to side is a two hundred millimeter lands all right and then the final one is a arm's length okay, so if you wanna hold up your okay all the way out there what you see through the sioux that your little okay circle there that's going to be about a four hundred millimeter lens so if you see a little birdie on the the tree out there and you do this and you go it fits and they're really nicely but I only have a two hundred millimeter lens it's probably too small and we're going to do eight hundred too eight hundred is if you can obliterate it with your thumb just like your thumbprint not your entire thumb but just like if you were to put an imaginary thumbprint on a glass wall in front of you and cover it up that's what an eight hundred millimeter lens looks like so when you go out and you look at the moon which is exactly two hundred eighty six thousand miles away, chances are that you're going toe put your thumb and it's gonna be a lot smaller than your thought in fact you'd be surprised that you could put your pinkie up and it's going it's going to obscure the moon I know when you see the moon coming up over the horizon it seems huge oh did you see the moon tonight? It was huge it's the same size it was last night and you could cover it up with your thinking. All right, so those air just rules of thumb estimates to get in the ballpark all right, so our group of lenses we started fifty we have wider angle lenses and kind of something to think about as we go wider angle is that as you go further away from fifty these lenses become more difficult to build their more costly and I believe they are more difficult to use and the same is true with the tele photos the further up from fifty ago the bigger, the more costly they are and the more challenging and difficult they are to use. If I was running the john gringo photography academy as a freshman, you would be issued a fifty millimeter lands and that's what you would shoot pictures and maybe midway through the first year you would get access to the thirty five and one hundred and then maybe as second year students then you can start using the twenty four in two hundred and then is you go on to the upperclassmen level, then you're up to sixteen, four hundred and when you're on graduate level, then you go all the way to fourteen to eight hundred the techniques and skills become more difficult, and so I think sometimes it's challenging when somebody who has more money than sense just says, okay, well, I'm gonna buy all the extreme best stuff out there because they haven't really built up to it and so I think using the lenses it's okay to kind of buildup, okay, I met a two hundred millimeter lens now and I'm thinking in the future I want to get a three hundred or four hundred that's, ok that's a good learning curve. You will learn from your mistakes and two hundred and you will become much more shit using four hundred and so it's. A good learning process stepping stone. And so I wanted to go out and shoot a bunch of siri's of photos that showcased all the focal lengths like I did on the road, but in different places just to have a different feel of what it looks like. So here we are at the university of washington with the fifty millimeter lands let's go wide angle and we can see the steps that lead up to red square. Those of you who know it here in seattle, we do have a red square in seattle it's completely different than the one in moscow. But that's the sixteen millimeter lens we see our stairs and let's zoom in back up to fifty. So here is our normal lens, and they were going to go up to one hundred some construction going on down there. And once we get into four hundred, we start getting a nice, clear view of mount rainier, which is since we're doing distances in this class seventy miles from seattle, and then we'll just bring it back down to fifty, just for comparison. And so I've been working with all these different lenses just trying to go to different places and so do another one here in seattle think this's on fourth avenue we got our fifty millimeter lens lets go backto wide angle we'll jump all the way back to sixteen and then we're gonna work our way doesn't want to stop twenty four there we go okay, now we'll go back up to fifty and onto telephoto and now we're going really narrow in on what's our wonderful traffic in seattle and then back down to fifty and so I took this set of lenses down to utah and arizona this is false kiva in canyon lands. Normally you would want to shoot this with wide angle lens, but I decided we'll tell you what let's shoot the whole syriza lenses and see what sort of result we getting what we consume in on so just kind of having these focal links in your mind's eye helps you decide what lenses right for that particular situation and we'll go all the way back down to our sixteen millimeter lands so one of the places I wanted to take it was into zion national park up two angels landing now this one is actually shot with a fish eye lens, which we're going to get into in another section, but it curves the horizon, which is why things look a little rounded here and kind of funny, and I started zooming in, and I found something kind of interesting. Do you see it yet? You see anything interesting yet might be able to see it now, and so there's some rock climbers that had just woken up after spending the night on the wall, and they have one of their port alleges that they were sleeping off, and so we'll bring it back to our full fisheye effect here. Actually, the main reason that I went up to angels landing to shoot was to shoot down the other side of the valley, and so starting with the sixteen fisheye and then sixteen and going through my lens is trying to find something to focus in on, and there was a really nice looking tree right in the front lawn of the zion lodge here, and I noticed that there was a group of people right down at the base of the tree, and they were they were playing some sort of game, and so I thought, the whole serious, and you know what? I'm gonna go hike down, and I'm going to go right down to the base of the tree. I'm going to sit at the base of the tree, I'm going to turn the camera around and photograph exactly where I wass when I took this photograph, so I wasn't able to go fast enough to actually make it in this shot here in self timer was not long enough on that, but if you want to know where I was when I took the shot is I was up here with all these people and so let's zoom back with four hundred and two hundred, and this is angels landing in zion national park in southwestern utah, and now you can see those people that were hanging out on the grass right there in front of me, all the way down to a fish. Eilat all right, so one final siri's on this, but this is different than the other siri's in this siri's jen are beautiful model is going to be staying the same size in every photograph, and for those of you who are into filmmaking, this will be known as a hitchcock or a dolly zoom, and so what I'm gonna do is I'm going to shoot with different focal lengths, but I'm going to move the camera, and what I'm gonna do is I'm gonna first go wide angle, and I'm going to move the camera a little bit closer now. Notice what happens to the background notice? What happens to gen is her body starts changing shape a little bit and distorting a little bit with our wide angle lenses. Now as we go into the tele photos getting back to normal watch what happens to the background and notice how the background becomes smaller in size and that compression effect she's getting compressed against those stairs and let me just back up a leased to the fifty millimeter so we can go back down to the normal view and so when we have a subject that has a lot of working space and there's just unopened sidewalk I can use any photograph to photograph her it's just a matter of where I want to be and how her proportions are going to look as well as everything else that's in the photograph and it really depends on the story that you're trying to tell in that photograph there isn't one that's best there's one that's best for a certain type of story and so this is one of those personal decisions that you get to make having a bit of range is a nice perhaps this is why zoom lenses are popular or having a wide variety of primes sorry popular so that you can get these different effects so that should hopefully shore up your knowledge of focal lengths and what the different lenses are for so we could move forward to the next section but let's check in and see if there's any final questions we can take it this point all right so john this's from eileen m and her question is our older lenses like one hundred thirty five millimeter nikon lens from the seventies usable on new nikon digital cameras? Yes, it is s o we're going to talk more about that arena of subjects in section three on features and technology and just kind of has a real briefer to start with. Nikon has not wanted to alienate large portions of their customer base at any one time, and so they have tried to keep a system that progressed and I think of it as an evolution all right? And so you can evolve forward now having said that, did I say yes, sir? Probably yes, I should have said probably yes, because it depends on a few things generally, you are pretty safe with nikon, with any product made within ten years forward or backward of where the other product iss so something right now is going to be good for something probably made ten years ago and that's why I kind of hesitate because she could probably use it. The question is, is how much compatibility or manual things for instance, that lens is definitely manual focus, but how well it matches up exposure wise to their camera? I don't know and so it's a troubling issue because nikon, as I say, they don't want to anger large portions at any one time and what ends up happening is that you start angering small groups of people on a frequent basis and there's going to be an issue with some new zealand's is that I'm going to explain about that I'm gonna warn you be careful about buying these brand new lenses because if you own this era of camera they won't work right on there and so that will be something that I will hopefully clarify in the features and technology section will a fifty millimeter dx linds on a dx camera give the same field of view as a fifty millimeter fx lens on an fx camera? Ok, so that answer is no because they're talking about the same lens on cameras that have different size sensors. And so with the smaller sensor it's going to be a narrower angle of view and so they're going to see something a little bit differently now the lens itself it's the same lens and so the characteristics of that lens will hold true whether that's how much flare it has or the depth of field that it has. All of those things are the same, but it's just that resulting image is going to be a little bit different. And I think that seems to be what a lot of people just have trouble comprehending again, and hopefully by the end of this class we'll have a better understanding of sort of the difference between all the angle of view and the dx and the fx and just really, getting your head wrapped around that you on. The other question was from yolanda, with a couple of votes that was what's the best lens for blurring out the background. I'm using outdoor it for outdoor portrait photography. And so I think we're going toe. I see a little bit about that. Well, actually, that we're going to talk more about that in an upcoming section on aperture, because there's multiple effects on ways to blow out the background, right, there's, three different ways, and you can use all of one or a little bit of the three different systems and kind of combine up all those different techniques for eighteen it out. So there's, a lot of different ways, and I think we'll address that mohr with visuals.

Class Materials

Bonus Materials with Purchase

Nikon® Lenses Part 1
Nikon® Lenses Part 2
Nikon® Lenses Part 3
Nikon® Lenses Part 4
Field of View
Nikon® Lenses Part 5
Nikon® Lenses Part 6
Nikon® Lenses Part 7
Nikon® Lenses Part 8
Nikon® Lens Data

Ratings and Reviews


Outstanding class! This is a must own. You will refer back to this class many times during your photog career. John has put a ton of work into this class and it shows. Being able to download the slides and other Nikon glass info is wonderful. Even if you're not a Nikon shooter you will still gleam tons of information from this class, John covers in great detail the strength and weaknesses of each lens and when you might consider using it. I was expecting a good class, but this turned into an epic class. I watched multiple videos several times. The only bad thing I can say is I "had" to order a few more lenses! Thank you John Greengo for making a truly amazing class.

Anna Fennell

Wow! What a course! Very in depth, lots of valuable information. John instructs with great knowledge and integrity. I have taken other online courses, NOT from Creative Live (my bad!) and was left feeling like a monkey who had learned tricks without understanding or knowledge. Now I feel I have the confidence to move forward on my photographic journey securely knowing how lenses function, what to look for and what price range I can expect. Bravo John! I'd love to see a 2020 update video as an addendum.

Fusako Hara

Finally I have some sense of what lens do, know what I have, what I would like to have, what lens to use, and how I can get images that I see. Best part of this session is it was made so clear, simple, logical, and practical. I am glad that I purchased this product. Now, I am going to look for more from John Greengo so I can take better understanding and take better images. Thank You.

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