Review: Seamless Follow Focus Gears

Tailor-made gears for any lens
By Sol March in Resources

Tired of dealing with rubbery one-size-fits-none follow focus gears? Perhaps it’s time to level-up to custom-fit seamless follow focus gears.

From slow reveals to split-second focus racking, nothing beats a good follow focus unit when you need the ultimate control over your focus adjustments. However, in order to use a follow focus, your lenses need gears that allow the follow focus to turn the focus ring.

Cinema lenses come standard with these gears built-in.

Cine lens with built-in focus gear

Still photography lenses– which many shooters use on Panasonic GH4’s and Red Epics alike– do not have built-in follow focus gears, so we need to add gears to use a follow focus with these lenses.

Flexible focus gear

The problem is that many aftermarket gears have one or more of the following issues:

  • Stretching — rubbery focus gears can get stretched out of shape and introduce play between the follow focus and the lens.
  • Dead-zones — adjustable focus gears have clamps or attachment points like a watch band that prevent a full 360° rotation of the focus ring. This is particularly problematic for modern lenses with fly-by-wire focus rings that don’t have hard stops.
  • Too narrow — narrow focus gears can lose their connection with the follow focus when used on lenses that extend when the focus ring is turned.
  • Slip — even rubbery focus gears can slip around on the focus ring, requiring frequent downtime to readjust the gears on the lens.

There are some great stills lenses, so I’ve been on the hunt for the perfect follow focus gears for a while. Then I discovered Sean McCurry’s custom-made follow focus gears. These gears appeared to meet all of my requirements– they were rigid, seamless, wide, and best of all each gear was tailor-made for a particular lens.

Seamless Focus Gear

Sean sent over a few sample gears for us to test and we put them to work immediately. Simply put, these gears deliver. Read on for all the details.

Just the Stats Ma’am

Lens Compatibility

These gears currently support a wide variety of lenses, but if you have a lens that is not already supported, you can send in measurements to get a custom gear made for the lens. This means that you can add a follow focus gear to virtually any lens.

We tested follow focus gears for the following lenses:

Lenses equipped with focus gears

Materials & Build Quality

The follow focus gears are made out of plastic. The striations in the plastic are indicative of a 3D printing process, which explains how these gears can be custom designed to such precise tolerances.

3D printed focus gears 3D printed focus gears

The plastic focus gears are lightweight (~18g) and do not add a significant amount of weight to the lens that could throw off your rig’s balance. Despite being lightweight, the gears are have proven to be quite solid and have not taken any damage in the field.

Lightweight & strong focus gears

Fit

The first time I slid the focus gear on the Sigma 18-35mm f/1.8 lens, I smiled.

The gear fit so closely to the lens barrel that I was afraid it was too tight and might damage the lens, but in fact, the fit was perfect. Once the gear slid over the focus ring’s rubber coating, it stayed put as if part of the lens.

Sigma 18-35mm f/1.8 with seamless focus gear

With such a close fit, removing the gear from the lens’ rubber-coated focus ring does require a bit of pressure. By working the gear off slowly, it came off safely without leaving any marks on the lens.

The gears for the other lenses were custom-made based on measurements I had sent in. It turned out my measurements were a bit too tight and caused the focus rings to bind and skip a bit.

Sean offers free revisions for anyone not happy with the fit, and after a few revisions, we had gears that fit perfectly for each lens. A set of spacer rings were even provided to help with finding the right fit for any lens.

Spacer rings for custom focus gears

These seamless gears are particularly useful on native MFT lenses– such as Panasonic’s fast 25mm f/1.4 prime— which feature a unique style of fly-by-wire focus control. Not only do these lenses lack hard stops on the focus ring, but the amount of focus throw varies based on the speed at which the focus ring is turned.

As a result, the lens’ focus throw could even be over 360° of rotation, which means adjustable focus gears are unusable (due to the clamp on the gear). With these custom-made seamless focus gears, we can finally use a follow focus with native MFT glass.

Panasonic 25mm f/1.4 with seamless focus gear Native MFT lenses with seamless focus gears

Performance

The gears performed very well with standard follow focus units such as Zacuto’s Z-Drive and Fotga’s DP500II2. There were no issues with slippage or skipping, even during fast rack focusing with a speed crank.

Focus gears mesh well with follow focus

The gears are designed to cover as much of the focus ring as possible. This gives you more flexibility when positioning the follow focus on your rig. It also means that you are less likely to run into issues with the follow focus disengaging from lenses that extend as focus is adjusted.

Wide focus gear

Finally, you can also request a custom outer diameter for the gears. This allows you to keep the follow focus at the same distance from all of your lenses, saving you time when swapping lenses on set.

Gears for different lenses with the same outer diameter

A Viable Alternative to Rehousing Lenses

Though there are several good reasons for rehousing still lenses for video work, it is an expensive endeavor. If all you really need is a solid gear to use your lenses with a follow focus, these seamless follow focus gears are a cost-effective and near-native solution.

These focus gears stay put well enough that you could consider them a semi-permanent solution, but the nice thing is that they can be easily removed as well, so you’re not locked into particular way of using them. If you frequently shoot with a follow focus, you can safely leave the gears mounted on the lenses. Otherwise, you can keep the gears in a pocket and slide them on whenever the need arises.

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