How Flexible Are Canon’s New Flex Zooms?

Canon announced their new Flex Zooms last month with a slew of features that seem to check all the boxes that professional cinematographers have been asking for. But how true to their name are they?

First… some quick history on Canon’s modern cinema zoom family.

Back in 2011 (ish) Canon rejoined the cinema lens field with the introduction of their 14.5-60mm and 30-300mm. Both lenses were offered in EF OR PL mount. Not both. For a short period, Duclos Lenses offered a replacement mount for either lens that allowed you to swap back and fourth, but it wasn’t ideal since a lot of people coming from EF to PL wanted to keep the metadata that the EF models provided. This simply wasn’t possible at the time so we discontinued that conversion shortly after launching it.

Compact Zooms. EF OR PL.

Shortly after those to pro zooms came the 15.5-47mm and the 30-105mm which proved to be much more popular than anticipated. But they suffered from the same exact technical limitation. You could purchase them in EF mount OR PL. but you couldn’t swap them. We took what we learned from the previous zooms and started working on a more elegant solution. Thus the Multi-Mount was born! My absolute affection for alliteration was the source of the name, but the solution was far from unique. The interface was inspired by the same threaded mount solution used by Cooke, Angenieux, and a variety of others for decades. What was unique was the integration of this sub-mount into the two aforementioned Canon compact zooms. We removed a few layers of the mechanical components at the rear of the zooms and attached our newly design Multi-Mount sub-mount which allowed users to swap between mounts in a matter of seconds. The conversion also included a clever mechanism that allowed users to make adjustments to the integrated back focus pin which was otherwise obstructed and required disassembly to access. Nearly every Canon compact zoom lens that we sold came with our Multi-Mount system. It was a no-brainer for rental houses and owner operators that needed the flexibility of a professional zoom lens without needed to double their investment and buy one of each lens. We probably cost Canon a few sales as a result but I can live with that guilt. Can’t you?

CN-E Primes. EF Only.

With the release of two compact zooms and our Multi-Mount system, we had an influx of clients asking us to integrate the Multi-Mount system into the Canon CN-E Primes. We looked into it and found there simply wasn’t enough room, mechanically, to accomodate the sub-mount and necessary hardware. But we did find that there was room, just enough, for a hard PL mount conversion on the CN-E primes. When Canon heard we were working on a PL conversion they asked to meet with us to discuss. Their engineers told us it simply wasn’t possible. …We delivered the first batch of PL mount CN-E primes a month later. 🙂

Cine-Servo. EF OR PL.

In 2014 Canon unveiled their hybrid Cine-Servo zoom which was very popular due to its convenient zoom range, 17-120mm. Similar to the previous zooms, it was available in PL or EF mount but still not both. They attempted to appease customers by offering a mount swap service. Their intentions were good but the practicality of this was just unrealistic. The swap included sending your lens to Canon’s service center, purchasing the new parts, waiting for their techs to perform the conversion, and then waiting for it to be shipped back. Not ideal for working pros that own or rent their equipment. The same inconvenience was offered for the 50-1000mm which came out later in 2014.

Flex Zooms. Flexible?

This brings us to Canon’s latest Flex Zooms. When I saw that Canon was calling them “Flex”, I was immediately skeptical. All of the other specs appeared ideal. Full Frame coverage. Fast, constant T-stop. Ideal zoom range at a reasonable size….OH HOLY JEEBUS available in PL OR EF. I assumed all hope was lost. All of the features of the Flex zooms were exactly what we’ve been asking for but these weren’t particularly unique specs. Fujinon’s Premista Zooms are very similar and have already proven themselves as the go-to professional full frame cinema zooms and Cooke’s Varotal/i zooms are… similar. I scoured through Canon’s marketing pamphlets and press releases to find any mention of lens mounts or what they were claiming made them “flexible”. Nothing! Eventually I found one tiny mention of “user-interchangeable mount” buried in a feature list on another dealer’s website the day the press release went out. I was still skeptical. Maybe some data-entry person at the big box store just copied and pasted from another product or it was simply a mistake when they created their product page. There still wasn’t any mention of interchangeable mounts on any of the official Canon material. I started reaching out to get clarification from Canon. Fast forward a few weeks and I’m meeting with some Canon’s technicians in a tiny back-room at NAB to get the real details about their new Flex zooms.

(If you’ve read this far, thanks for being a fellow Lens Geek.) It’s at this point that my skepticism switched to excitement. Canon’s technicians proceeded to show me the procedure for swapping the mounts on the new Flex Zooms which took a mere two minutes. Not only did Canon finally give us the flexibility that we wanted – but they did it in an elegant, well thought-out way. This is a clear signal from Canon that they’ve learned their lesson and that they value their professional customers. I’m sure to some, this may seem silly. But to me this is Canon saying to their highest value customers “yes, we see that you’re competent and we trust that you can do this on your own”. The entire conversion requires two screwdrivers, a basic clean bench, about two minutes, and some common sense. I was able to snag some photos of the process at the Pacific Northwest Lens Summit at Koerner Camera (special thanks to Kari Fouts for letting me use her bench for a few minutes). Let’s take a look at the step-by-step.

Remove four screws that hold on the simple red-anodized beauty ring.
This exposes the eight sub-mount screws that join the mount assembly to the chassis. There are four jacking screws that align the mount to the lens axis (super easy for zoom tracking adjustments). These just need to be loosened, not removed.
Remove the eight screws that join the mount assembly to the chassis.
This releases the entire mount assembly along with the tiny PCB that relays metadata to the mount. The PCB uses pins and pads which means there’s no delicate wires or clips to fiddle with. There’s a locating pin on the chassis that aligns with a slot in the mount assembly which makes it nearly impossible to misalign the mount assembly to the chassis.
When you purchase the EF model, there’s no Cooke/i data port on the side of the lens. So when/if you want to switch to PL, the data port comes with the mount kit and can easily be installed with just four screws on the side of the lens. The EF model has a cover plate that hides this connector otherwise. Again, super slick pins and pads. No wires or clips!
And lastly, back focus couldn’t be easier. There’s a rubber flap that exposes two screws. The smaller black one locks the back-focus adjustment and the larger gold pin provides the adjustment. Simply turn it and the entire rear group compensates for correcting back focus.

And that’s it! Like I said, it would take an experienced lens tech about two minutes to perform this swap. The procedure is exactly the same going from PL to EF or EF to PL. The lenses can still only be purchased in PL or EF, but the mount kits will be available at launch which I obviously encourage everyone to add to their lens. But if you don’t think you need both EF and PL, don’t worry! You can always purchase the mount later. There’s no downside.

Speaking of purchasing – as always, the complete line of Canon Cinema lenses are available from Duclos Lenses including the brand new Canon Flex Zooms which are available for Pre-Order now. I hope you found this post helpful or perhaps even inspirational. If so, please feel free to share it or leave a comment below.

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