Canon’s new EOS R platform raises some interesting questions when it comes to lens selection. Of course you can go straight for the new hotness that is the RF mount lenses. However, thanks the the shorter flange-focal distance of the RF mount, you can also adapt virtually all DSLR lenses to work on the camera too. Probably the most important, and useful of these is Canon’s own EF lenses.

The question then becomes, should you focus on buying RF glass across the board, or are EF lenses still a viable option?

To EF or RF?

The question of whether to EF or RF depends on a number of factors. Put simply, if you’re playing the very long game, the RF mount is the future for Canon. Ultimately sooner or later the EF mount is going to be supplanted by RF. However, in the shorter term — by which I mean the next 5-10 years or so — the EF mount is still going to be a viable option.

For starters, there’s the simple reality that Canon doesn’t currently make every lens option in RF mount. There are plenty of lenses, right now, that you simply can’t get without adapting an EF lens; for example, a 35mm f/1.4L or a tilt shift, or a 100mm macro. Now it’s entirely certain that over the next several years, Canon will be rolling all these options out to the RF platform, but they’re not there now.

If you’re still shooting with Canon DSLRs — for example, I’m still using my two EOS 5D mark IVs, and I don’t expect to replace them for another year or two — you’re going to need to have EF lenses.

Additionally, if you’re using, or planning on using, one of the many “cine” style cameras out there — for example, the Canon C200, C300, C500, BlackMagick Design URSA Mini Pro or Pocket Cine 6K, or most of the camera from Z-Cam — EF lenses are something you’re going to continue to need to consider.

As things stand now, at the time of writing, there’s only one RF mount Cine style camera; Canon’s own Cinema EOS C70. However, it’s expected that there are more RF cine cameras in the works.

From a technical perspective on the lenses, there are some reasons you might want to lean one way or another too.

For starters, all RF lenses are focus by wire designs. While there are some EF lenses that are focus by wire — all the STM lenses — the majority have mechanically coupled focus rings. This has some implications when it comes to manually focusing these lenses, especially in video situations.

On the other hand, RF lenses, have the advantage of being typically smaller, lighter, have better optical quality, and increased features (such as longer zoom ranges, or image stabilization) that aren’t otherwise available on an EF predecessor. Additionally, RF lenses have a new programmable control ring that I’ve found to be quite handy at times — though the control ring can be had with adapted EF lenses with the control ring mount adapter.

Ultimately though, what might be the biggest deciding factor between the two mounts, at least for me, are the costs. All of the RF lenses are both new enough, and in high enough demand, that they’re still carrying the new lens premium. Eventually the costs will come down, but probably not for several years to come.

As a point of comparison, consider the 24-70mm f/2.8 options. An EF mount Canon factory refrub 24-70mm f/2.8L II USM and a control ring mount adapter can be had for around $1920. Buying a new lens, brings that cost up to $2100. However, buying the RF mount variant will run $2300. Granted, the RF mount lens has IS, but then so do the EOS R5 and R6 bodies too.

On an even more expensive side of things, the the difference between an RF 70-200mm f/2.8 and an EF one plus a mount adapter, is between $400 and $725 depending on whether you get a new or factory refurbished EF lens.

Admittedly, all of these RF lenses have some advantages over their EF predecessors. The 24-70 has image stabilization, and in conjunction with the in-body stabilizer of the R5 and R6, gets a very impressive 8 stops of shake reduction. Likewise the 70-200mm f/2.8 is 2 inches shorter, and 2/3rds of a pound lighter than it’s EF counterpart.

In either case, there’s certainly value to the improvements of the RF lenses, but the question  you have to ask yourself is how much are those improvements worth to you. There’s a lot that can be done with $200-$700.

My Advice:

The question, to me at least, comes down to what can I do to get the best bang for my buck. While RF lenses are definitely the future, and in some cases, the future is now, there are plenty of really good EF lenses available now and at substantial savings. That said, I’ll over up my usual advice for people asking about buying lenses.

First, don’t go around looking for general advice on what lens you should buy next. Lenses, like your photography, are a personal thing, and the right lens for you is not necessarily the right lens for someone else.

Before you start asking around about what lenses you should by, sit down and honestly evaluate what you’re problem areas are, what you really need, what you want, and what sounds like it’s important because the marketing makes it sound impressive.

Start with where you’re finding you’re having problems. Are your existing lenses not long enough? Wide enough? Fast enough? Is there a certain focal length you’re always shooting at and maybe it’s just not doing it for you?

Second, be honest with yourself about your needs, wants, and what just sounds good. It’s real easy to see numbers like 8 stops of image stabilization and think that’s really important to have; but maybe it’s not, or not for the added cost over something else.

Don’t get me wrong, I’m not here to poo-poo technological advancements. A better IS system, faster focusing, more resolution, etc. are all useful things to have. They certainly make better images, and make it easier to make better images. However, more purely for the sake of having more won’t make you a better photographer.

Once you’ve considered your needs and your situation, sit down and make a plan. I like to keep 2-3 years of future purchases in mind at this point. I have good enough glass that I’m not hurting, so I can be both strategic about my purchases and I can afford to bide my time and wait for a the best deals I can find.

It’s also important to keep in mind that while cameras are advancing rapidly, the pace isn’t such that you can expect a lens now to be utterly obsolete next year. The RF mount is almost certainly designed to support extremely high resolution lenses, likely much higher than the EF mount’s designers ever envisioned when they were designing the mount in the early 1980s. However, many EF lenses now, especially L series ones, are more than capable of meeting the demands of at least 50 MP cameras. With camera’s like the EOS R6 at only 20 MP, it’ll be a few generations and many years before a good EF lens won’t be adequate to support that sensor.

Finally don’t be afraid to alter your plan over time. Your needs may change, new lenses will be released, and new information about a product may change your mind about it.

This was certainly the case for me. When Canon announced the RF 100-500mm f/4.5-7.1 IS USM I was dead set that I was going to get that lens to replace my go to EF 100-400mm f/4.5-5.6L IS II USM. It’s one of my most used lenses, and the 100-500 looked like a really good upgrade. However, as reviews came out on the 100-500, I became aware that you can’t collapse the lens past 300mm with a teleconverter attached, and this really concerned me. As a result, for the time being I’m sticking with my 100-400 and biding my time when it comes to big RF telephoto zoom and I’ll see what else Canon offers as a big pro telephoto zoom. Or ultimately I may get some time with the RF 100-500 and my concerns over the teleconverters will prove to be unfounded — or the price will come down enough that it’s enticing enough to buy on those grounds.

In any event, the short of it is that EF lenses are still perfectly viable options for RF platform users. It doesn’t hurt either that they can save you some money and still provide great quality images. That said, in the long run, say more than 10 years down the road, they will be supplanted. But for the next decade? Go for the glass that best does the job and fit your budget; whether that’s EF, RF, or a combination of both.