using a 2x TC on a 70-200 f2.8 v1 for sports

Question

I'm thinking about getting the 2x TC to use with my 70-200 for sports for additional reach. Is it worth it? I use it on my 5dM4.

Answer 1

It depends a lot on which 70-200mm lens you're using. It also depends upon which extender/TC you're using. How much image quality you're willing to sacrifice for a little more "reach" also enters into the equation. 2X extenders/TCs always come with a noticeable image quality hit, but some more than others.

The only zoom lens I've personally used that can handle a 2X extender and still keep up well with sports subjects in terms of autofocus is the EF 70-200mm f/2.8 L IS II. [One can presume the EF 70-200mm f/2.8 L IS III, which is virtually identical to the II save for improved antireflective coatings on some lens elements and the external paint color, would perform at least equally as well.]

The original EF 70-200mm f/2.8 L IS and the even older non-IS EF 70-200mm f/2.8 L do not AF fast enough with a 2X Canon extender to be very usable to me for the sports I shoot. The first IS model may be fast enough for what sport you're shooting though. The even narrower baseline of the EF 70-200mm f/4 L series limits their AF speed with an extender as well.

In practice, I've found that when shooting with the 5D Mark IV + EF 70-200mm f/2.8 L IS II, cropping after the fact gives about the same or even slightly better overall image quality as using an EF 2X III extender unless I really need the pixels for a very large display size. You also keep the faster f/2.8 aperture, which can be vital if shooting sports under lights at night or inside a gym. Putting a 2X extender on an f/2.8 lens makes it an f/5.6 lens for exposure purposes. Dropping from 1/800 or 1/1000 to 1/200 or 1/250 for high school athletes is the difference between a reasonably crisp shot and a blurry mess due to subject motion. The only other option when losing two stops of aperture is to kick the ISO up by two stops: I'm usually already at ISO 3200 under lights.

The waters are a little murkier when it comes to using an EF 1.4X III. You only give up one stop of aperture in return for 1.4X image size. You also get less image degradation due to the additional lens elements than with a 2X. But extenders and TCs are really designed to be used with tele-primes, not zoom lenses. The view generally held among pro sports photographers during the EF era was that Canon's extenders are optimized for their 300mm f/2.8 lenses current (or in the final stages of development) at the time that particular edition was released. The EF 2X III and EF 1.4X III, released in 2010, are at their best when used with the EF 300mm f/2.8 L IS II, introduced in 2011. The EF 2X II and 1.4X II, released in 2001, were optimized for the EF 300mm f/2.8 L IS, released in 1999.

Most third party teleconverters are not the same optical quality as Canon's extenders. Many (e.g. Kenko, pre-2012 or so Tamron, pre-Global Vision Sigma, etc.) were all made in the same factory and only differed in their branding marks. There were 4 element and 7 element versions of both the 1.4X and 2X TCs. With Sigma's Global Vision (ART, Sports, Contemporary) line the 1.4X TC is pretty good when used with Sigma GV lenses, but the 2X isn't near as well regarded.

Then there's the issue of third party compatibility. I've got a Kenko 2X Teleplus Pro 300DGX bought around 2010. It works fine with my older Canon DSLRs like the 50D, 7D, and 5D Mark II. All were released before 2010. When used with a 5D Mark III (introduced in 2012 running updated firmware released around 2014), 7D Mark II (2014), and 5D Mark IV (2016), it locks the camera up and the only way to unlock the camera is to remove the TC, turn off the camera, remove and reinsert the battery, and turn the camera back on. Reportedly the newer versions of the Kenko work with some of those newer cameras, but you need to be sure the one you're considering is up to date to work with the 5D Mark IV and whatever firmware version you're running in it. Sigma's and Tamron's TCs may be updatable via the USB docks they introduced around 2012.

The only exception I've found to this is when imaging the Moon from a stable tripod using a remote release and mirror lockup (or Live View). But by 400mm f/5.6, atmospheric turbulence is a very real consideration even on a FF camera. However, if you've got very good 'seeing'¹ then an extender can give you more details of the lunar surface than cropping without one.

_{Canon EOS 7D + Kenko 2X Teleplus Pro 300DGX + EF 70-200mm f/2.8 L IS II. Tripod mounted with wired remote release and mirror lockup. 400mm, ISO 200, f/8, 1/125.}

_{¹ 'Seeing' is the term astronomers use to describe the conditions in the Earth's atmosphere that affect how astronomical objects appear from the surface of the Earth. Turbulence in the atmosphere can cause major degradation of astronomical objects. Cooler temperatures, such as in mid-winter, usually mean less thermal turbulence and less moisture in clear skies. The higher an object is in the night sky, the less air the light from it is passing through before you see it from the ground.}

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The following doesn't specifically answer your question, but I think it does address your root issue: getting more "reach" when shooting sports. Feel free to consider it or not.

Since 2015 my default telephoto setup for shooting sports has been a Canon 7D Mark II + EF 70-200mm f/2.8 L IS II. I already had a 5D Mark III when I bought the 7D Mark II, and then later moved to a 5D Mark IV as my primary FF camera. When shooting sports I've continued to use the 7D II as my telephoto body and use the FF for a wide angle zoom, usually a 24-70mm f/2.8 L or 24-105mm f/4 L IS if the weather looks a little iffy.

For most everything else I shoot, I use the 5D Mark IV as my primary body. Sometimes that's with a "standard" angle zoom or prime on the 5D Mark IV and the 7D Mark II with the 70-200mm becomes the secondary body for a few supplemental longer shots. At other times the 5D Mark IV has a telephoto lens and my 5D Mark III has a wider angle lens. Sometimes it's just the 5D Mark IV and whatever lens I need. It all depends on what I'm shooting.

In 2024 a used 7D Mark II in reasonable condition is fairly affordable. It probably wouldn't be much more than a Canon generation III extender. Here are the advantages I have found to using the 7D Mark II as my telephoto sports body:

• The pixel density of the 7D Mark II is the same as the 50MP FF 5Ds and 5DsR. Yet it shoots at double the frame rate of the 5Ds/5DsR. The 7D Mark II is even faster than the 30MP 5D Mark IV. It's like you're shooting in "crop" mode with a 5Ds without the speed penalty.

• Pixel density is the real metric when considering "reach". If you crop a FF to the center part of the frame the same size as an APS-C sensor, you're giving up the same ground in terms of noise, depth of field, etc. that you'd give up using an APS-C sensor to begin with. But with the 7D mark II, you still have 20MP instead of the 12MP you'd have left cropping the 30MP 5D Mark IV that narrow.

• The high number of frames per year I put on my telephoto body when shooting sports dwarfs the number of frames per year I put on my FF body shooting it as the wide angle body for sports plus using it for everything else I shoot, COMBINED! I shoot a lot of other stuff, but I rarely shoot more than a couple of hundred frames per shoot for my other stuff. I shoot at least a couple of thousand frames with the telephoto body at a high school football game. Rather than put all of that wear and tear on the more expensive FF body, I put the vast majority of it on the cheaper APS-C body. My 7D Mark II has well over 200,000 shutter actuations on it and still works as well as it did the day I got it brand new.

• I first started using the 7D Mark II when my FF body was a 5D Mark III which doesn't have flicker reduction. This is revolutionary when shooting under flickering lights at typical youth league and high school sports venues. Of course the 5D Mark IV has also offered flicker reduction since it was introduced in 2016, but flicker reduction was the only reason I even considered the 7D Mark II when it first came out in 2014. I'd had more than enough of the poor AF consistency of the original 7D and had abandoned it as my telephoto body after buying a 5D Mark III to replace my 5D Mark II, which has even worse AF for sports than the original 7D! The 7D Mark II is what the 7D should have been. The AF system is extremely close to the same level as the 5D Mark IV. The image quality is also much better and less noisy than the original 7D.

In 2020, despite the COVID pandemic, we still had a fall high school football season in our area. As photographers, though, we were restricted to shooting from behind one end line the entire game. Previously we'd always been allowed to shoot from anywhere outside the 25s and also allowed to walk back and forth from one end to the other as long as we walked behind the teams on the sidelines. The 70-200mm, even on a high pixel density APS-C body, was not really enough to reach the far end of the field.

I'd been tempted forever by the Sigma 120-300mm f/2.8 | Sports and broke down and bought a used one before the 2021 season in case we had the same restriction again. It of course gave me more reach on the 7D Mark II than the 70-200mm. But at the long end on my 5D Mark IV the 120-300mm images weren't quite as sharp as my 70-200mm on the 7D Mark II. The AF wasn't quite as consistently accurate, either. But the 120-300mm lens' longer reach on the 7D Mark II meant I didn't need to crop as much so the slight additional blur in some ever-so-slightly misfocused shots didn't really show up compared to cropping/enlarging a sharper shot from the 70-200mm, and sometimes the 120-300mm did nail focus and I got a better picture than the 70-200mm could have given me when enlarged to the same subject size. It was marginally better with the 7D Mark II than the 70-200mm because I didn't need to crop near as often, or near as much when I did, enough so that I used it for a couple of seasons.

But that thing was like carrying a bowling ball around on the end of a stick¹ plus I now needed the 70-200mm on the 5D IV to bridge the gap between the 120-300mm on APS-C (192-480mm FF AoV) and the 24-70mm on FF. Me getting older didn't help any. I sold the Sigma lens in late 2023 and went back to cropping tighter with the 70-200mm when needed. For what I paid for the 120-300mm it probably wasn't worth the marginally better images, even though I got about two-thirds of what I paid for it (from map camera in Japan) when I sold it to KEH.

_{¹ I also had to upgrade my monopod. My ancient Manfrotto 680B and especially the 234RC tilt head on it were not quite up to the task of the heavier lens. I got a heavier Benro MAD49A + Oben VH-A30.}

Answer 2

"Is it worth it?" is a question that's difficult to answer. But a 2× teleconverter will definitely stress and show the weaknesses of any lens. Of all the zooms you could put it on, the 70–200mm f/2.8 will handle it about the best. It will definitely help you increase your long range without having to purchase heavier long-focal length lenses.

If you're making money with your sports photography, eventually the time it takes to switch in your TC will cost more than having a dedicated body plus long-focal length lens. But you'd have to me shooting a lot of sports events in a dynamic way (such as sidelines at professional sporting events). Your photo income will dictate when the "is it worth it" inflection point shifts. In the meantime, a 2× TC paired with a high-quality zoom lens is probably a cost-effective option.

Answer 3

IME, putting a 2x on a 70-200/2.8 is going to be a bit worse than an equivalent longer zoom such as the 100-400/5.6 in Canon, or 80-400/5.6 in Nikon. Such lenses are generally reasonably good, but they are notable compromises... zoom is also a compromised design by nature.

One way to get a lens like a 140-400/5.6 telephoto is to simply add 2x stronger telephoto elements to the 70-200/2.8 design. The primary difference then is that the stronger telephoto elements are actually part of the design and are assembled/tested/optimized as a unit; as opposed to added after the fact to "convert" the lens.

So you are making an even more compromised solution compared to the "economy lens" options...

"Worth it" is entirely subjective and it is also dependent on many other variables. You may find that you get approximately equivalent results just from cropping; because that's really all a teleconverter does, it turns your sensor into (more of) a crop sensor (but there IS a potential advantage).