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Nikon Lenses: The Complete Guide

Lesson 10 of 57

Equivalent Aperture

John Greengo

Nikon Lenses: The Complete Guide

John Greengo

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Lesson Info

10. Equivalent Aperture


  Class Trailer
Now Playing
2 Nikon Lens Basics Duration:14:05
3 Focal Length: Angle of View Duration:11:44
4 Focal Length: Normal Lenses Duration:06:41
6 Focal Length: Telephoto Lens Duration:16:22
7 Focal Length Rule of Thumb Duration:15:59
8 Field of View Duration:10:06
9 Aperture Basics Duration:15:35
10 Equivalent Aperture Duration:07:17
11 Depth of Field Duration:12:58
12 Maximum Sharpness Duration:09:50
13 Starburst Duration:06:48
14 Hyper Focal Distance Duration:18:42
15 Nikon Mount Systems Duration:26:41
16 Nikon Cine Lenses Duration:07:06
17 Nikon Lens Design Duration:20:56
19 Nikon Lens Vibration Reduction Duration:06:28
20 Image Quality Duration:04:44
22 Nikon Standard Zoom Lenses Duration:21:56
23 Nikon Super Zoom Lenses Duration:06:07
24 Nikon Wide Angle Lenses Duration:08:28
25 Nikon Telephoto Zoom Lenses Duration:16:48
26 3rd Party Zooms Overview Duration:06:06
27 3rd Party Zooms: Sigma Duration:16:02
28 3rd Party Zooms: Tamron Duration:07:31
29 3rd Party Zooms: Tokina Duration:03:50
  Class Trailer
Now Playing
1 Nikon Prime Lens: Normal Duration:13:50
2 Nikon Prime Lens: Wide Angle Duration:14:17
3 Nikon Prime Lens: Ultra-Wide Duration:09:29
7 3rd Party Primes: Sigma Duration:07:19
8 3rd Party Primes: Zeiss Duration:03:25
9 3rd Party Primes: Samyang Duration:05:34
10 Lens Accessories: Filters Duration:30:44
11 Lens Accessories: Lens Hood Duration:13:40
12 Lens Accessories: Tripod Mount Duration:04:41
15 Macro Photography Duration:19:11
16 Nikon Micro Lens Selection Duration:18:29
17 Fisheye Lenses Duration:17:59
19 Tilt Shift Lenses Duration:06:00
20 Building a Nikon System Duration:05:16
24 Nikon Lens Systems Duration:11:18
25 Lens Maintenance Duration:10:54
26 Buying and Selling Lenses Duration:17:36
27 Final Q&A Duration:12:08
28 What's in the Frame Duration:03:29

Lesson Info

Equivalent Aperture

Something we need to talk about because it is a kind of a common thing that we do have to come back and answer questions on is the different size sensors in our camera and the different lenses we use on him and how things appear to us in there. And so one of the terms that has come about recently and this did not exist when I was in college equivalent am pitcher was not a topic we ever talked about back twenty years ago, but now we have people who are using the same lands, but on two different cameras with two different size sensors, and there are some things that are saying and some things that are different, and we need to kind of further address this issue. All right, so a fifty millimeter lands on a full frame camera, sees forty degrees, thirty five millimeter lands on a crop frame camera sees forty degrees. So these two photographers are taking not quite the same photo but a nick wiggle it photo, and so they're seeing the same thing from side to side that's one aspect that is exac...

tly the same. And so that part is the same, but a fifty millimeter, one point four lands and a thirty five one point four lends those air different lenses all right now, it's the same aperture. Okay, so the one point for in the one point for those two photographers can work in the same low light environments and have the same shutter speed the same s o the whole same exposure what's different is that a thirty five millimeter lands has a different depth of field than a fifty millimeter lands and that stays true no matter what sensor you put behind it so it's always a thirty five millimeter land so there is there is no such thing in my mind as a croplands lenses are the focal length that their number is whatever that numbers says on that lands that's what it is there's no changing that fat there's different cameras in front sensors and that's what we have to be aware of so when we're shooting with equivalent apertures a fifty one foreigner thirty five one for these two photos taken with different lenses are similar they're the same angle of you they have the same light gathering ability they're taken at the same exposure but there is a slightly different depth of field if you'll notice in the background there's a red bush it is a little bit more out of focus on the left photo than it is on the right photo not much it's a very subtle difference and if we're to change this toe two f to there now more closely aligned and so the thirty five millimeter, one point four lens has what many people now termed as an equivalent aperture of f to which means depth the field wise it looks like a like a deaf to lands but when it comes to light gathering it's still a one point four and so it's a little tricky when you're trying to compare lenses between different sensors because there's there's angle of you there's light gathering ability and then there's depth of field and so you can have these three different factors and people get in all sorts of arguments in the chat rooms and the forums about well I have the equivalent of a fifty millimeter one point for then somebody will jump in and say no you don't it's not a fifty one point for it's the equivalent of a fifty one point two or fifty two and they're like why can shoot in the same low light? I have the same angle of view and so it depends on what's most important to you angle of view light gathering ability or depth of field and so with the crop frame sensors what tends to happen is that you get a little bit more depth of field now is that good or bad is more depth of field good or bad? Should I feel being good or bad about having a crop frame camera? It depends on what you're shooting sometimes it helps sometimes it hurts it's a tradeoff is all it isthe let's try this with three hundred millimeter lands, so we have a three hundred millimeter lens which sees a seven degree angle of you in order to do that same shot with the crop frame, you need a two hundred millimeter lands. Now this is a major advantage because the two hundred millimeter lands is way cheaper than a three hundred millimeter lance, so advantage to the crop frame user. Alright, so they're both set at five point six and we have our subject in focus and we have our background out of focus. Well, if you want shallow depth of field, the full frame user is at the advantage now because of three hundred renders a shallower depth of field than a two hundred millimeter lands. And at every aperture, if you compare f ate full frame still has the shallower depth. The field, if you compare, meant f eleven, it still has a shallow depth of field because it's in reality it's a three hundred millimeter lands three hundred millimeter lenses always no matter who makes him, no matter what brand, no matter what era you bought it in he's gonna have shallower depth of field than a two hundred millimeter lens if their shot at the same aperture. And so when we get down here to five, six clearly a shallow depth of field, we have to close the three hundred down to an f ate in order to make it look more similar so we could say that the two hundred millimeter lands on this crop frame body has an equivalent aperture of f ate and that's in its visual appearance not in any setting you need to make on the camera you don't need to adjust anything in the camera it's just it's visual appearance looks more like an f ate lance and for some people this is a big deal for other people it's like makes no difference and so if somebody tells you you're wrong and you don't have things right, well yeah, technically they may have something correct, but it may not be the most important thing in the world just something to be aware of if you have full frame, you could get shallower depth of field a little bit more easily if you have crop frame, you can get more depth of field a little bit more easily and for a landscape photograph that could be really nice nice but just to be honest with you folks there's a lot of photographers they get really snobby about shallow depth of field and if you don't have a crop frame sensor, you're just not meeting their standards and it's just different choices people make and the results of them so equivalent aperture fifty one four thirty five one four they see the same angle of view that the same light gathering ability but they're effective. Look of the depth of field. The effect of look of the aperture is different. If you have the same aperture, you have the same low light ability they can shoot in the same dark wedding hall. Same focal length gives you the same depth of field, but these lenses are not the same focal length, so they're going to give you different depths of field by a slight amount. In fact, I would be I would love to do it. Attempts to go down to the local park show two photos to people what's different about these two photos, and I would say that probably ninety five percent of the people would not be able to pick out the difference between these at all. So this is something that photographers like to argue about, but I need to address because we're all photographers, and we love to argue.

Class Description

The world of interchangeable lenses can be both exciting and confusing to all levels of photographers. Nikon® Lenses: The Complete Guide with John Greengo will help you choose the right lens and get the most out of all of your lens investments.

John Greengo is the master of making complex photography concepts easy to understand and in this class, he’ll bring all of your Nikon DSLR lens options and operations into focus. 

You’ll learn about:

  • Focal length and aperture
  • Nikon® zoom lenses
  • Which lens accessories to buy
  • Third-party lenses
  • Maintaining a lens system

John will cover the full range of Nikon lenses, from ultra-wide to super-telephoto, zooms to primes, fisheye to tilt-shift. You’ll learn how to match the lens to your needs and get insights on the best ways to use it.

Whether you are looking to buy a new lens or just want to get the most out of what you already have, John Greengo will help you to become a master of the Nikon® lens.



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.


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.