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Lens Accessories: Extenders

Lesson 46 from: Canon Lenses: The Complete Guide

John Greengo

Lens Accessories: Extenders

Lesson 46 from: Canon Lenses: The Complete Guide

John Greengo

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Lesson Info

46. Lens Accessories: Extenders


Class Trailer

Class Introduction


Canon 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


Aperture: Maximum Aperture


Aperture: Equivalent Focal Length


Aperture: Depth of Field


Aperture: Maximum Sharpness


Aperture: Starburst Effect


Aperture: Flare


Aperture: Hyperfocal Distance


Camera Mount System


Canon Lens Compatibility


Canon Lens Design


Canon Lens Composition


Canon Lens Shape


Canon Lens Coating


Canon Lens Focusing


Lens Autofocus


Canon Lens Image Stabilization


Canon L Lenses


Image Quality


Canon Zoom Lenses: Standard


Canon Super Zooms


Canon Wide Zooms


Canon Telephoto Zooms


Prime Lens: Normal Lenses


Prime Lens: Moderate Wide


Prime Lens: Wide Angle


Prime Lens: Ultra-Wide


Prime Lens: Short Telephoto


Prime Lens: Medium Telephoto


Prime Lens: Super Telephoto


3rd Party Lenses Overview


3rd Party Prime Lenses


3rd Party Zoom Lenses


Lens Accessories: Filters


Lens Accessories: Lens Hoods


Lens Accessories: Tripod Mount


Lens Accessories: Extension Tubes


Lens Accessories: Extenders


Macro Lens: Reproduction Ratio


Macro Lens: Technique and Choices


Fisheye: Technique and Choices


Tilt Shift: Techniques and Choices


Make a Lens System Choice


Choosing A Portrait Lens


Choosing A Sports Lens


Choosing A Landscape Lens


Best Lenses for You


Lens Maintenance


Buying and Selling Lens


What is John Greengo's Favorite Lens?


Lesson Info

Lens Accessories: Extenders

extenders. Thes are the tele converters. That air, called Double Er's canon, has two of these. They have a two times and a 1.4 converter, and these air designed for magnifying the focal length of your lands. Now these latest ones have been flooring coated to resist dust prints and fingerprints, and these loans elements on the front can be fairly exposed because you notice the's extend here. This is going to be important in a coming slide, they extend into the back of the lens so they're very exposed when you're mounting these on and off. And a lot of photographers air kind of keeping the knees in the pocket because they're adding them and taking them off lenses on a regular basis. So 300 millimeter lands on our camera. We're gonna add it in just like an extension tube. 1.4 converter has now made our 300 millimeter lands like a 420 millimeter F four lands. We're gonna add in a two x tele converter. And now we've taken this 300 we've turned it into a 600 millimeter F 56 lens. So I wanted...

to do a comparison. I, of course, have to do a visual comparison. So here's our beautiful city of Seattle. This is shot, by the way, within 85 millimeter lands to start with, and we're going to mount a 300 millimeter lands on both a full frame camera and a cropped frame camera, and we're going to use all the different tele converters in all the combinations. So with just a 300 those air, your frame lines of what you would see straight through the cameras. And so let's take a look at the straight 300 shots. Now. What we can do is we can add on tele converters. Now we have a 300 on the left. We have the equivalent focal length of 480. It's not a 480 millimeter lens. It's on a crop frame camera, but that's the angle of view that it sees. Let's add our 1.4 converter, and we're going to get a little bit closer. We're gonna add on our two times converter, and we're going to get a little bit closer again. And so I wanted to run a test about image quality on this because there's arguments as to which one should be best, because if we want to go in and like, we want to identify a person up here on the Space Needle. Well, this this one over here is using a crop frame camera. Full frame should be better, but it's smaller and we have to enlarge it more. So there's a trade off and this one we're not adding a tele converter, so we don't have those extra lens elements. That should be a better quality image. But we have to enlarge it Mawr to get it up to this size. And I wanted to run the test here, but it was too windy of a day, so I had to take it in the house and do it kind of in the studio. And so, using the same type of set up, using full frame and crop frame, going in and trying to look at a very small portion, blowing this up to see which combination is going to give me the sharpest if I really need to go in to a small area to see the detail. The worst of the bunch was with the straight 300 the reason was it was because I just had to enlarge the image so much. Number four was a tie between the crop frame camera straight with the 300 a 1.4 converter, and what's kind of interesting is you look at the numbers for 24 80. Those are pretty close. Next in the line, basically is the next biggest number at 600. The next in the line is the next bigger number. And so, whatever the effective focal length ISS is, really, if you need to get out there, you want to use whatever means necessary to get out there. And so the 300 with the two x on the crop frame camera got me the sharpest image because it was the largest image on the sensor. And so this may very depending on the cameras you use and the exact tele converters and the exact lenses that you use. So if you have one of these extenders, you are supposed to mount the extender to the lens first. If you mounted to the camera, the camera says, there's an extender and I have no idea what you're attached to. And so there's a level of communication that happens right then, if you attach it to the lens and then you attach it to the camera, the camera knows, Oh, I've got a lens and a two times converter on here at the same time. And so that's the system that you're supposed to use now you're not supposed to do this. But what if you wanted to add a 1.4 and a two times converter? All right, really. I mean, I don't recommend this for quality reasons, but sometimes you really need to reach out there. You can't do it because this front part extends into the lens in front of it. And you can't do this with this telly extender, and you can't do it with certain lenses. But there is a trick to getting around it, and it's the device that we just talked about. The extension tube, that hollow tube. You can mount the hollow tube between the two of them, and you can mount the two tele converters together, and this is gonna work in virtually all situations that dependence on exactly the products you're using. But it's a great way of going that extra distance is, I say, I don't recommend this for all right shortness reasons, but there are a few special occasions where you just need to reach out as far as you can on these things. One quick word. One of the things that I don't have in my class is aftermarket telly, extenders or extenders, and that's because there really are none that I can recommend out there. There's a bunch that you can buy, and I've tried some of the lower end extenders out there, and I am just completely dissatisfied and quality. You can try him on your own, but I'll just give you fair warning that the quality levels are substantially lower than the canon wants. Canon makes the two of them here. The 1.4 magnifies the image by 1.4 times. It does lose one stop of light. There is no free lunch in these sorts of things. There is a price to be paid for extending the lens out. With the two times converter, you lose two stops of light. There is a selection of lenses that you can see on screen here. These are the lenses that you can use the tele converters on without any other sort of extension tubes or adapters. For the most part, we're talking about l lenses that are telephoto lenses. There's a couple of tilt shift lenses in there. They're kind of the exception to the rule. And other than that, everything else is 70 millimeter l lenses and above in that category, and I every once in a while, we'll get somebody. Well, I want to put a tele converter on a 50 millimeter lands. Why would you want to do that? Um, it's almost just justus Chief to go by 100 millimeter lens trying to put a doubler on that. And so the Dubler is just don't make much sense until you get into these pretty decent telephoto lenses and you really need to have a pretty good quality lands because the tele converter is going to decrease the image quality. These air as good a tele converters as you're gonna be able to put on a canon camera. But they're not perfect. They are gonna lower the optical quality. That 14 is very good. The two X is not quite as good, but it's a very small way to have multiple large telephoto lenses, and I like it for my 300 because now I can have a 4 24 I can have a 605 6 in a relatively small package that doesn't have three gigantic lenses. And so you do need to have a very good lens to start with on this case. In general, I don't recommend using these on zoom lenses with 72 202 eights and 70 to 200 F fours are good enough quality that probably the 14 is okay. But I would probably avoid using the two acts on a zoom lens. It's just lowering the image quality a little too much. So I think that's it for the accessory section. So let's check in on questions. All right, Emily, let's start with you in the Okay, John, if the, uh, tele converter to isn't as sharp as the 14 and we have extension tubes, can we play the little trick of 14? Extension 214 Extension to and just continue out and get a better quality. Well, if you were to add a 14 extension 214 extender to a 14 You're getting the equivalent of two times Tele converters, so they are equal and magnification. But I would say that it's probably better just to use the two X than these two individual ones. I've never tried that. I'm it's not. It is more like it'd be better. Just a comparison of how maney lens elements are you adding to the formula. And so you still end up adding Justus many elements to the formula. And so I don't think that is a creative solution, but I don't think it's gonna It's gonna win out. Yeah, go ahead with the extension tubes. Do you always want amount? Those first on the lens as well? I think you would want him out Those as well in the lands. Good point. Thank you. Great. And then just you talked about this a little bit, but question came in to put the extenders or the extension tubes on a big heavy lens. Doesn't that make the union between that lens and the camera fragile because of the weight on the lens? Yes. And so this is true both with extension tubes and extenders, and so cannons. Latest extenders said that they had no improvement in image quality between the two version two and version three. And what they did improve was, I believe, the weather resistance and the strength of the tube. And so this is one of the reasons why I'm not a big fan of some of the aftermarket ones, because if they're not made to really tight tolerances, there's just a little wobble or a little bit of play. And really, any play is bad. And so this is one of the reasons why I would prefer to use one tube versus multiple tubes, whether it's extension tubes or extenders. And so, yeah, that is not something there where you want to try to put on 10 extension tubes just to get your lens really far away, because that's not gonna be a very stable device. So good observation. Great. Yeah, go ahead. Filters. What about aftermarket filters? I noticed there's quite a price difference in, uh, Canon Filters versus aftermarket. Well, Canon doesn't make very many UV, and they don't have much in the way of a variety of filters. And so there are, ah, variety of lens manufacturers that have a variety of prices and a variety of qualities for the better quality. I stick strictly to be plus W. It's a German manufacturer that makes very good quality glass. Spend an extra 2030 bucks on the filters in many cases, but I think it's well worth it in the long term on a good lands. So I'm gonna address this a little bit further in the lens maintenance section, but I I prefer well, I tend to have some of the better lenses, so I want to have a better quality filter on there. I don't want to stick one of the really cheap pieces of glass, and the reason is kind of unusual. It's not because of the optical quality, although that's a portion of it. Let me see if I can find one of my lenses. Now the filter on Here, take this off here. This has a brass ring, and I think this is a metal table, and so you can really tell you can tell the sound of a brass filter, and I don't think any of these lenses have a cheaper filter on it. But the aluminum has a very distinctly different sound, and it has a very hollow, tinny sound, and this has a really nice, subtle, solid metal, which means that when I squeeze this and put it on, it's less likely toe bend out of shape. The softer aluminum, you know, you crank it on, they're a little too hard that soft metal it can catch in there and they can cross threat. And if you've ever had a gorgeous sunset that you're trying to unscrew a filter on your camera, you just don't want to deal with that sort of thing in the field. And so I prefer to get a little bit of extra quality of my filter, so I don't have to worry as much about it cross threading and binding up and getting caught on the lands. One more question from Will G. Santiago. So can you tell us again? What is the downside of using an extension is that he's in the Philippines as well. Thanks for coming in. So the extension tube or the extender? Do you know, I don't know. So the downside of using the extension tube, which is the hollow focusing, too, is that you can't get his close is a macro lens, and you can no longer focus on infinity. So you're not gonna walk around with this on your camera? Doing general photography? This is something where you've decided. Oh, there's something close up. I need to focus. My lens doesn't focus. Close enough. I'm gonna add this to it, shoot my pictures, and then take this off. And so it's per use, period. The tele converters. They are losing one or two stops of light. And you only use that when you need that extra telephoto capability. So when you need close up or when you need telephoto capability special tools to solve those problems.

Class Materials

Bonus Materials with Purchase

What's in the Frame? HD
What's in the Frame? LOW
Field of View HD
Field of View LOW
Lens Keynote Parts 1-4
Lens Keynote Parts 5-8
Canon® Lens Data

Ratings and Reviews


I so appreciate what a good teacher John is. I wish I would have known this much about lenses when I first started out buying my lenses. It was hard finding information about lenses. I didn't want to spend money on a lens I wouldn't use. The better understanding we have about our gear the better photographers we will be. I have never seen a class like this. Invaluable...yes I bought the class! I am really impressed with the high quality photography classes available on Creative Live!


This was a great class not just about the lenses that Canon offers but also how each lens works. As usual, John's slides are alway informative and entertaining. There is a phrase: John has a slide for that! I am not even a Canon user and found this class to have great information for the use of each specific lens. Great work John! Thank you Creative Live for another great class!

Tami Miller

Have loved the other John Greengo classes I've watched & purchased - and this is another winner! Having been a high school/college science teacher, it is refreshing to take a course with someone who not only is extremely experienced, seems to be a computer having stored so much knowledge, but is equally concerned about making the information truly understandable to different levels. And he shares the information using every tool he can: slides, video, interactive presentations, and great quizzes. I learned so much about my Canon lenses - and lenses in general with their many components. I am excited about testing each of mine to see what macro ratio they handle, and especially appreciated the tutorial on testing each for their specific quirk that affects super sharpness. This class is great whether you own Canon lenses or not. Thanks John Greengo!

Student Work