LockCircle Announces PrimeCircle, a Cinemod for Zeiss ZF and X-Circle, a Semi-Permanent F to EF Mount Adapter

I am partial to Nikon lenses, and I've often recommended them to many people for cost alone, but if you've got some money to spend, Zeiss certainly makes one of the best Nikon mount lenses. If you choose to cinemod them, you've got the next best thing to a PL mount lens. LockCircle, maker of the LockPort and the LockCircle Body Cap, is getting into the cinemodding game with some interesting products. The first is X-Circle, a semi-permanent lens mount that not only provides a solid F to EF mount adapter to the rear of the lens, but turns the lens 90 degrees to make the lens information more accessible. They also introduced PrimeCircle XT, a complete Zeiss ZF cinemod including de-clicked aperture, and PrimeCircle Ring Kits, a DIY lens mod that allows you to add a professional follow focus ring and standard 95mm front mount yourself.

Here's a description of the PrimeCircle series of products:

  • Teflon Impregnating Hard Anodizing (TIHA) for heavy duty, scratch resistance and lifetime work.
  • Innovative X-Circle Cine-Lock (pat.pend.) with improved locking mount for cine-style focus work.
  • Exclusive SIDE INDEX VIEW (pat.pend.) for easy to read focus/aperture settings - EF Mount Only
  • Ergo-Gear, innovative follow-focus gear featuring also handheld ergonomics grip.
  • Front Mount with 95mm size mount for professional cinematographers matte-boxes and accessories
  • Front Mount with circular engraved grooves for superior flare and reflection control.
  • Filter thread 90mm for PRIME-CIRCLE 90 Series professional filters - coming soon
  • Easy to mount kits with "step by step" instructions (RingKits)
  • Side Code Barrel with engraved lens size - immediate lens coding for production crew reports  (XT only)
  • Custom Flight Cases
  • PrimeCircle Ring Kits and XT with these Zeiss lenses: 18mm f/3.5, 21mm f/2.8, 25mm f/2.8, 25mm f/2, 28mm f/2, 35mm f/2, 35mm f/1.4, 50mm f/1.4, 85mm f/1.4, Makro 50mm f/2, Makro 100mm f/2

The X-Circle is a really interesting design, and it makes it a lot easier for the AC to check distance markers and adjust aperture if necessary. X-Circle will work on all Nikon lenses as well as Zeiss ZF lenses. PrimeCircle is basically their entire cinemod line of products, and the Ring Kits are the cheapest option. The Ring Kits include the X-Circle and EF back cap, focus gear, 95mm filter and front lens cap. You're going to need a separate kit for each Zeiss lens that you want to mod, as the focus gear and 95mm filter are specific to each Zeiss lens. The Ring Kits will run you $239 for just the filter thread and focus gear, and $399 if you also want the X-Circle F to EF mount.

The PrimeCircle XT is a complete mod of the Zeiss ZF set of lenses. They include everything from the Ring Kits, but also have a de-clicked aperture and a metal housing with the focal length of the lens engraved on the side. You can buy single lenses or an entire set with a flight case, but right now they aren't offering any way for you to send in your own ZF lenses to have them cinemodded.

X-Circle and the Ring Kits are both available now, but you'll have to contact LockCircle for pricing on the PrimeCircle XT lenses and len sets, as they don't list prices. I would imagine that the full lens kits will not be cheap, but for a professional option, they should compare favorably and be a cheaper option to Zeiss CP.2 lenses.

LockCircle is also developing lens filters, some of which will be compatible with a mattebox they will also be releasing. Check out all of their products below.

DISCLOSURE: LockCircle is an advertiser on No Film School.


Your Comment


Solid Nikkon F and G mount to Canon EOS for less money. Although you don't get the 90* turn on the lens.


March 20, 2012 at 7:39AM, Edited September 4, 7:54AM


" I would imagine that the full lens kits will not be cheap, but for a professional option, they should compare favorably and be a cheaper option to Zeiss CP.2 lenses."
especially considering the Cp.2's are just rehoused ZF mount glass!

March 20, 2012 at 8:25AM, Edited September 4, 7:54AM

Christian Hubbard


I am not aware of this, does Zeiss proclaim it? Just because they share the same focal lengths?

Anyone know??

March 20, 2012 at 9:49PM, Edited September 4, 7:54AM


It's not that simple - yes the CP.2s are more or less rehoused ZF lenses, but they are much more selective in the glass that they choose. So the reason the lens costs more is not just the rehoused body - they also pick better and more consistent glass in a set, they set a T-stop for the lens, and they also eliminate breathing (at least enough for it to not be noticeable).

March 20, 2012 at 11:24PM, Edited September 4, 7:54AM

Joe Marine
Camera Department

The CP.2 lenses also have more aperture blades, if I remember correctly. Still, I'd happily go for these Primecircles XTs - just trying to decide if I want to go this way or another.

March 21, 2012 at 3:04AM, Edited September 4, 7:54AM


I think its a good idea but for 400 bucks you might as well send your lens to duclos and have it done by the best for cheaper

March 20, 2012 at 9:08AM, Edited September 4, 7:54AM



March 20, 2012 at 9:53AM, Edited September 4, 7:54AM


The Lock Circle people are the same jokers behind the "BabyPrimes" scam.

They seem to be really trying to hide this after their big embarrassment. Notice how there is no information on the website about who they really are. However, thanks to google there are clues on-line you can use to find out the connection.

Honestly, no matter how you dress up a ZF lens it is still a ZF lens, it does not make it a cinema lens. Like painting a lightning bolt on your bike to make it go faster. Here's the Zeiss statement


March 21, 2012 at 4:38PM, Edited September 4, 7:54AM

Hunter Gatner

Hunter.....revolutions (also small) are made by warriors and not by negative people writing without knowing.
Enjoy other peoples ideas and work. Your life will smile to you! Express yourself and shot your stories. Cheers Robin Hood

March 26, 2012 at 4:41AM, Edited September 4, 7:54AM

Robin Hood