EF-S or EF or L or IS - WHAT DOES THIS NOMENCLATURE MEAN?

[EPT1955]

I am buying all new Canon equipment to replace my Nikon D70. I have settled on the Canon EOS 7d camera (need built-in flash and to shoot movies), the challenge is what lenses to buy. Price is not necessarily an over-riding concern. I have spent hours reading everything I can find - thank goodness for Digital Picture.com, what a great help!


My problem is I cannot find anything anywhere which gives a clear and concise explanation of the difference between EF, EF-S and L levels. L apparently stands for Canon's professional line, but what about the other two - are they compatible with the 7d? Are they appropriate or or are some features useless on a 7d?


I am going to purchase two lenses. The first is the EF 70-200mm f/2.8L IS II USM (I wish the reviews and F/stop were better for 70-300mm or the 100-400mm). I could certainly use the longer focal length for race car shooting - Sebring and LeMans both of which involve night time work.


I cannot begin to settle on a shorter focal length zoom (24 to 70mm or around that) for studio table top, and close people candid portraits (political events).My specifications are I want my short focal length zoom lense to have F/2.8, have Image Stabilization (IS) and have weather resistant construction for inclement weather. I shoot the PanAmericana Challenge in Mexico and the IS is a terrific feature for holding out the window and wildly shooting the huge crowds.


Please help - thanks for any input you may have...

[Sean Setters]

EF - Stands for "Electro-Focus." EF lenses can be used on full-frame cameras and APS-C (1.6x) crop sensor cameras.


EF-S - Stands for "Electro-Focus: Short back focus." These lenses are specifically designed for use with APS-C (1.6x) crop sensor cameras and will not work on full-frame cameras. A Canon 7D, being a crop-sensor camera, can use either EF or EF-S lenses.


L - Stands for "Luxury." It is Canon's professional top-of-the-line lens series.


IS - Stands for "Image Stabilization." If a lens has IS, it can compensate for some camera shake.


I'll let others give their suggestions as far as lenses go...

[neuroanatomist]

Welcome to the TDP Forums!

My problem is I cannot find anything anywhere which gives a clear and concise explanation of the difference between EF, EF-S and L levels. L apparently stands for Canon's professional line, but what about the other two - are they compatible with the 7d? Are they appropriate or or are some features useless on a 7d?

EF = electro-focus. Almost all Canon lenses do this (the exceptions are the tilt-shift series and the ultra-macro MP-E 65mm lens). EF lenses work on all current Canon dSLR cameras (and also on Canon EOS film cameras).


EF-S =electro-focus with short back focus. These lenses work only on Canon dSLRs with 1.6x crop sensors - that includes the 7D, the xxD line e.g. 50D, and the Rebel series. EF-S lenses do not work on 1-series (FF or 1.3x crop) or 5D/5DII FF bodies. With a couple of exceptions (e.g. 17-55mm f/2.8), EF-S lenses are low-to mid-level consumer lenses (i.e. not the best quality). The EF-S image circle is covers only the 1.6x sensor, meaning these lenses are cheaper (less glass).


The L-series is Canon's professional line - the red ring around the barrel indicates the best image quality and build quality. Many (but not all) L-series lenses are weather-sealed (note that L lenses other than the supertelephotos require a filter for full sealing - so, the 70-200mm needs a filter to be sealed). All L-series lenses are EF lenses, meaning they work on any EOS camera. Since they are designed for a FF image circle, when used on a crop body you get some benefit - even with L lenses, there are distortion/vignetting issues, and those are most evident in the corners which are 'cropped' out on a smaller sensor.

I am going to purchase two lenses. The first is the EF 70-200mm f/2.8L IS II USM (I wish the reviews and F/stop were better for 70-300mm or the 100-400mm).

The EF 70-200mm f/2.8L IS II USM is an excellent lens! It hold up well to a 1.4x teleconverter, giving you a 98-280mm f/4 lens that maintains weather-sealing (and the constant aperture is better than the variable aperture of the 70-300mm). For more reach, I usually use my 100-400mm when it's bright and dry, but at twilight or in the rain, it's the 70-200 II with or without the 1.4x extender.

I cannot begin to settle on a shorter focal length zoom (24 to 70mm or around that) for studio table top, and close people candid portraits (political events).My specifications are I want my short focal length zoom lense to have F/2.8, have Image Stabilization (IS) and have weather resistant construction for inclement weather.

That's a tough call - the lens you specify really doesn't exist in the Canon lineup (although if you believe the rumor sites, a 24-70mm f/2.8 IS lens is coming soon - but then again, it's been 'coming soon' for years).


IMO, the EF-S 17-55mm f/2.8 IS is the best general purpose zoom on a crop body like the 7D. Although it is a little short of L-series build quality, the optical performance is equivalent to L-series lenses. I use mine a lot, indoors and often outdoors as well. But, it's not weather-sealed. When it's raining, I use the 24-105mm f/4L, trading a stop of aperture for weather-sealing while keeping IS.


Good luck with your decisions!

[wickerprints]

As others have mentioned, EF stands for electronic focus, and the "-S" in EF-S stands for short backfocus. Both types of lenses are compatible with current production EOS bodies that have APS-C size sensors (what Nikon calls "DX"). EF-S lenses, however, cannot be used on bodies that have larger sensors. The following recent production EOS bodies are NOT compatible with EF-S lenses:


1D Mark III, 1Ds Mark III, 1D Mark IV, 5D, 5D Mark II.


EF-S lenses are physically incapable of being mounted on these bodies, unlike Nikon DX lenses, which can still be mounted on FX bodies but the periphery of the frame will be dark (because the DX lens projects an image circle that is too small to cover the entire FX frame).


"L" designates the professional line of Canon lenses. The closest they get to explaining what makes a lens "L" is found in EF Lens Work III, Chapter 2:

The bright red line engraved on the lens barrel. And an L for “luxury.” The Canon EF lens L series possesses a level of quality sufficiently high to be called professional, designed to include groundbreaking image performance, outstanding operability, and resistance to weather and aging. “L.” This name is reserved only for those few lenses that can meet stringent standards of performance, using fluorite (an artificial crystal), a ground and polished aspherical surface, UD, super UD lenses, or other special optical materials. Optical design without compromise together with optical theory and precision engineering technologies that are as steeped in tradition as they are cutting edge. And the result of our relentless pursuit of these ideals is the L series of Canon EF lenses.

Please note that no EF-S lenses are ever given the L designation, despite some of them being of comparable optical quality.


Regarding a wide-angle (< 70mm), f/2.8 or faster, image-stabilized, weather-sealed lens, there is no such lens available for the Canon system at present. The following lenses are close:

1. EF-S 17-55/2.8 IS (not weather-sealed)
2. EF 24-105/4L IS (one stop slower)
3. EF 24-70/2.8L (not image-stabilized)

However, because weather-sealing is not especially robust for extending zooms (as opposed to weather-sealed primes and internal-focus zooms), I would not consider such sealing to be particularly essential. If you are willing to forgo sealing, then the EF-S 17-55/2.8 IS will be the ideal choice for your purposes on the 7D. Please note that Nikon also does not offer a lens that satisfies your four criteria. Indeed, Nikon offers no lens that satisfies the first three criteria--weathersealed or no, there is no lens wider than 70mm, f/2.8 or faster, with VR, in either FX or DX format.


While you did not ask for this information, there are no EF primes shorter than 100mm that are image stabilized. The shortest IS prime is the EF 100/2.8L macro IS, followed by the EF 200/2L IS and the supertelephoto series.

[peety3]

I am buying all new Canon equipment to replace my Nikon D70. I have settled on the Canon EOS 7d camera (need built-in flash and to shoot movies), the challenge is what lenses to buy.


My problem is I cannot find anything anywhere which gives a clear and concise explanation of the difference between EF, EF-S and L levels.
<div style="clear: both;"]</div>

With all due respect (and I do honestly mean that), how can you possibly have chosen your camera (and apparently at least one lens) before you know what these acronyms mean? The good news is you're quite safe with the 7D camera, but you ask if EF and EF-S lenses are compatible with the 7D; if you aren't sure what lens choices a particular camera has, you probably shouldn't be buying it.


For a more direct answer, here's the easy color code to all this:


EF lenses have a red dot near the mounting ring.


EF-S lenses have a white square near the mounting ring.


Canon EOS cameras have a red dot on the mounting ring. Any EF lens works on any Canon EOS camera.


Some Canon cameras have a white square on the mounting ring. If the camera has a white square, an EF-S lens will work on that camera. EF-S lenses won't work on a 1-series, 5-series, the old D30, the old D60, or the classic Rebel.


L-series lenses have a red ring near the filter mount, and extract a lot of green from your wallet during the purchase process.

[peety3]

I cannot begin to settle on a shorter focal length zoom (24 to 70mm or around that) for studio table top, and close people candid portraits (political events).My specifications are I want my short focal length zoom lense to have F/2.8, have Image Stabilization (IS) and have weather resistant construction for inclement weather. I shoot the PanAmericana Challenge in Mexico and the IS is a terrific feature for holding out the window and wildly shooting the huge crowds.

As others have said, this lens doesn't exist (from Canon at this time). However, IS is normally a factor when shutter speeds are in the range of 8/EFL to 1/EFL, but your "huge crowd" shots should be in outdoor lighting where you probably wouldn't have such a slow shutter speed. That's not to say that the IS wouldn't ever be useful, but it's probably of no use for the shots you mention.

[EPT1955]

Dear Peety3,


I truly appreciate your thoughts on how I got to where I am today. The Canon 7d was sort of a no-brainer as none of the more advanced cameras (Mark Series) have a built-in flash. This is a feature I use extensively to provide some fill when shooting in all types of conditions and a separate flash would not fit my on the go style for most of my work.. The 7d price is right and now that I know more about the lenses, if I want to upgrade the body, I can still use my EF L lenses.


My lens consideration has been purely driven by The Digital Picture reviews. I currently have a Nikon 18-70mm and a 70-300mm. I am very comfortable with these two lens sizes for 95% of my photographic work. Using these as the base, I searched the Canon offerings to compliment my needs within a significantly upgraded package.


Fortunately, my initial criteria had eliminated all EF-S lenses, unbeknownst to me. I would truly like to purchase the EF 100-400mm L IS USM, but the reviews were not fantastic when they used the EF 70-200mm L IS II USM as the baseline. Perhaps I am placing too much emphasis on the reviews, do you have any experiences to impart?


I am part of a race team which mounts a yearly campaign that include the American Le Mans Series including the 12 hours of Sebring and the 24 Hours of Le Mans. Given their lengths, night time shooting is just part of the equation. Using an ISO of 1600 or 3200 with the 100-400mm might provide solid results, but I am not sure.


The reviewer mentions a pincushion effect and I have a hard time getting my arms around this concept. I am not sure how this issue would impact my photography efforts.


Peety3, I really appreciate how candid you were, thanks and I look forward to any other thoughts you may have.

[neuroanatomist]

I would truly like to purchase the EF 100-400mm L IS USM, but the reviews were not fantastic when they used the EF 70-200mm L IS II USM as the baseline. Perhaps I am placing too much emphasis on the reviews, do you have any experiences to impart?

I have and use both with my 7D. The 70-200mm is sharper, focuses faster, and has a wider maximum aperture. It's the sharpest, best quality zoom lens that Canon makes. It's also several hundred $ more expensive. The 100-400mm has a broader zoom range (4x vs. &lt;3x), and is double the focal length at the wide end. Although the 100-400mm is slower focusing, it does fine for me locking onto and shooting birds in flight. If you only need to go to 200mm, get the 70-200. The 70-200mm + 1.4x extender is still a little better on image quality than the 100-400mm, but only gets you to 280mm. The 70-200mm + 2x extender is worse than the 100-400mm. If you need the 300-400mm range, get the 100-400mm.

Using an ISO of 1600 or 3200 with the 100-400mm might provide solid results, but I am not sure.

ISO 1600 is tolerable on the 7D. I'd stay away from ISO 3200. Keep it under ISO 800 if you can.

The reviewer mentions a pincushion effect and I have a hard time getting my arms around this concept. I am not sure how this issue would impact my photography efforts.

It wouldn't, unless you're in the habit of shooting graph paper or buildings with orthogonal grids of windows. In real life, you will notice barrel distortion (common at the wide end of wide angle zooms), but almost never notice pincushion distortion.

[peety3]

I truly appreciate your thoughts on how I got to where I am today. The Canon 7d was sort of a no-brainer as none of the more advanced cameras (Mark Series) have a built-in flash. This is a feature I use extensively to provide some fill when shooting in all types of conditions and a separate flash would not fit my on the go style for most of my work.. The 7d price is right and now that I know more about the lenses, if I want to upgrade the body, I can still use my EF L lenses.

The 7D is a phenomenal value, and an excellent camera. I do characterize it as a 'noisy' camera, but it does produce fantastic pictures. Two of our four cameras are 7D, and we're very happy with them as such.


As far as on-board flash, everyone is different, but I just don't see you using the onboard flash much if at all. Obviously if you don't own an external flash, it'll get some use, but they're never very powerful and they drain the camera battery, slowing down the overall operation of the camera. Three of our four cameras have pop-up flashes (40D does, 1D3 doesn't), and it's been at least two years since my fiance or I have used the pop-up flash. Granted, we have four 580EX IIs.

My lens consideration has been purely driven by The Digital Picture reviews. I currently have a Nikon 18-70mm and a 70-300mm. I am very comfortable with these two lens sizes for 95% of my photographic work. Using these as the base, I searched the Canon offerings to compliment my needs within a significantly upgraded package.

My advice to many people is simple: decide what lens you're going to buy next. Don't try to go two or three lenses out, at least until you have more than two or three lenses, etc. I started with the 24-105, which was the right lens to start with. I soon rented the 16-35, 70-200/2.8IS, and the 100-400. I shipped those three back knowing that I liked the 16-35, "needed" the 70-200, and didn't like the 100-400. I added the 70-200, found that I was missing the wide end, and added the 16-35. Next is a 24-70 to "replace" my 24-105.

Fortunately, my initial criteria had eliminated all EF-S lenses, unbeknownst to me. I would truly like to purchase the EF 100-400mm L IS USM, but the reviews were not fantastic when they used the EF 70-200mm L IS II USM as the baseline. Perhaps I am placing too much emphasis on the reviews, do you have any experiences to impart?

Ignoring my own advice, I have a wishlist that plans out my next 10 years (or so I think) of photography purchases. I can tell you that the 100-400 is not anywhere on that list, and the list goes so far as to include eleven white lenses (two zooms, nine primes; I am buying for two photographers though). However, that's based on a willingness to buy cameras so that I can put enough lenses on cameras for a particular shoot. It's about redundancy; I won't go out the door with just one camera, even on a weekend trip to Florida to visit my great uncle in a nursing home.


I will also suggest that you consider the EF-S 10-22 lens. It is a phenomenal value, and goes to show how the 7D can really be a money saver if you aren't needing the very finest in photographic performance. Those who want to shoot wide can either pay $1700 for a 7D and $800 for an EF-S 10-22 ($2500 total), or $2500 for a 5D2 and $1500 for an EF 16-35/2.8 ($4000). The only thing wider is the 14/2.8 prime, and that lens is $2200! A 1D Mark IV can't get as wide as the 7D/10-22 combo, even with the 14/2.8! FYI, the EF-S 10-22 is #2 on my wishlist.

I am part of a race team which mounts a yearly campaign that include the American Le Mans Series including the 12 hours of Sebring and the 24 Hours of Le Mans. Given their lengths, night time shooting is just part of the equation. Using an ISO of 1600 or 3200 with the 100-400mm might provide solid results, but I am not sure.

I'd say there's no way the 100-400 would be usable on a 7D in those conditions. I did a 36-hour team relay run in March. Each runner exchange point had one of those small "light tower" trailers, with perhaps four 1000w sodium vapor light heads. I took a Canon 580II flash on a PocketWizard for off-axis fill, and truly struggled with a 200mm f/2 on the 7D. All of my overnight shots were noisy, as I was probably pushing ISO6400 to get shutter speeds of 1/60th in the hopes of freezing the action. You might have more light than I did, but you'll need better shutter speeds and I don't think you'll have it.

[Sheiky]

The reviewer mentions a pincushion effect and I have a hard time getting my arms around this concept. I am not sure how this issue would impact my photography efforts.

You probably won't even notice it, because it's not that bad. And with the newer software it's very easy to control by lens-profiles. In the test the squares should be totally square, but with pincushion distortion they are slightly pushed inwards. While with barrel-distortion(mostly seen by wide-angle lenses, it stretches the boxes. Seen here for instance(in a worst case scenario)