Full Frame Finder

Included with the Full Frame Finder is a Full Format Eyepiece, and a Pelican-style carrying case. All the other components: including the PL and LPL Lens Mounts, are optional accessories, that need to be ordered with the Full Frame Finder.

Red Monstro / Raptor 8K (40.96 x 21.60mm, diagonal 46.31mm), and ARRI ALEXA LF and Mini LF Open Gate (36.6 x 25.54mm, diagonal 44.71mm) Any frame lines that fit within those dimensions are easily designed using the FrameFinder app. See the next question.

Download the FrameFinder app from the Mac App Store. There is also a Windows version available on request. Using the app, you can design up to three frame line sets to be visible at the same time. Then print them on high temperature plastic sheet, using a commonly available office laser printer. You then cut the design out using scissors, then install it in the Full Frame Finder through an access door covering a slot in the side. The only tool needed is a small Phillips screwdriver. The multiple frame line formats can be common center, common top, or anywhere in between. All frame line dimensions are defined in millimeters, accurate to two decimal places. The 9:16 Vertical format is possible as well, either alone, or combined with horizontal formats. The directions on how do accomplish this are detailed in the User Manual PDF document. Find the "User Manual" link on the Full Frame Finder page, to the right of "More Information".

PL and LPL mounts are available for the Full Frame Finder.  Canon EF, Nikon F, and several other still-camera lens mounts are available by special order.

Loosen the Neutral Mount Lock Ring Safety Screw, located immediately to the rear of the Lens Mount Adapter.  Rotate the Neutral Mount Lock Ring counterclockwise as seen from the front of the Finder.  Remove the Lens Mount Adapter. Then reverse the process to install the replacement Lens Mount Adapter. Be sure to properly align the pin in the Intermediate Mount, with the slot in the mount flange of the Lens Mount Adapter.  Tighten the Intermediate Mount Lock Ring firmly hand tight, then be sure to tighten the Safety Screw.  Refer to the User Instruction PDF document on this web site to identify these parts if necessary. 

Using a 2.5mm Allen driver, remove the four cap-screws from the spherical cover plate on the top of the Finder, remove the plate, insert the Anamorphic adapter, then attach it with the same four screws. This can be accomplished in 5 minutes.

Using a 2mm Allen driver, remove the three cap-screws that attach the Full Frame Eyepiece to the Full Frame Finder, then install the Super 35 Eyepiece using those same three screws. This can be accomplished in under five minutes.

Yes, there is a 3/8-16 threaded hole in the bottom of the handle assembly. Rotate the handle to the fully-forward position to gain access to the threaded hole.

There is a lever to loosen the front to back position adjustment slider, located on the left side of the Finder. A round knob on the right side allows you to rotate the handle downward and forward to a comfortable position for use. Be sure to loosen this round knob two full turns, before rotating the handle ratchet mechanism. Attempting to rotate the handle ratchet mechanism with excessive force, without fully loosening the locking knob, might damage the ratchet mechanism.


Yes. The amount varies depending on which Xpander you use. The amount of light loss is listed in the specifications for each Xpander.

Yes, the lens scales change. New removable adhesive scales with corrected markings are available to install on a lens converted with an Optica Magnus Xpander. 

Angenieux Optimo 24-290mm

Angenieux Optimo 17-80mm

Angenieux HR 25-250mm

Angenieux 17-102mm

Cooke 25-250mm

Cooke 20-100mm

Cooke 18-100mm

Cooke 20-60mm

These lenses all have a universal “neutral mount” on the rear end, just forward of the factory supplied PL mount.  There is a threaded collar located there, which you unscrew by hand, to remove the stock factory supplied PL mount, and replace it with the Xpander, which has a PL mount on the rear. 

Note: the Angenieux 17-80mm does not have the
Universal Mount. An Xpander available for this lens by special order.

Yes, the Fujinon Premiere zoom lenses, by special order:




The Optica Magnus Xpanders are designed for mirrorless digital cinema cameras, such as the ARRI Alexa series of cameras, the Sony Venice series of cameras, and the Red Digital cameras. They are NOT to be used with film cameras with spinning mirror-shutters. To attempt to install an Optica Magnus Xpander on a camera with a spinning mirror/shutter WILL shatter the mirror.

No. Some zoom lenses were designed to cover the smaller “Academy Aperture.” Later lenses, such as the Angenieux 24-290 Optimo, were designed to cover the larger “Super 35” aperture (also known as the “Silent Aperture”)  Consequently there is one Xpander designed for the Academy Aperture lenses, to enlarge the image to fill the S35 Open Gate. There is another Xpander for lenses, such as the Angenieux 24-290 Optimo, that were designed to initially cover the larger Super 35 Aperture, to enlarge those lenses up to S35 Open Gate.

It’s all about minimizing light loss.  You could install the Academy to Open Gate Xpander on a lens designed to initially cover the Super 35 Aperture, but it would have more light loss than an Xpander specifically designed to expand the larger Super 35 Aperture to Open Gate. All the Optica Magnus Xpanders are custom designed to best optimize specific applications, with minimum light loss, yet retain excellent image quality.

Yes, you can do the installation yourself, without any

First, mount the unmodified lens, with the factory provided original PL mount attached at the rear of the lens, on your camera. Then carefully ascertain the lens holds focus on a target 10 feet (3 meters) away, throughout the zoom range. If it does not hold focus, you will need to have the lens and camera properly collimated to factory flange-focal distance by a qualified service technician, before proceeding.

Then, if the lens holds focus throughout the zoom range with the original factory PL mount, unscrew the threaded locking collar at the rear of the Cooke or Angenieux Zoom lens, just forward of the factory supplied PL mount. Remove and set aside the original factory PL mount. Store it in a safe place.

Inspect and verify the two mating surfaces: on the rear of the lens universal mount, and on the the front of the Xpander, are free of grit, stray hairs, etc. Verify that you align the slot in the lens flange on the rear of the Xpander to be at the 1:30 o’clock position, when viewed from the front of the lens, to properly mate with the index pin in the PL mount on the front of the camera. There is a pin in the back of the lens universal mount that mates in one of the slots in the front of the Xpander. Pick the slot in the Xpander that locates the slot in the PL mount flange at 1:30 o’clock. Make sure that pin is seated in the slot on the Xpander, before tightening the threaded locking collar. 

You can slide the ring on the Xpander rearward toward the PL mount, to visually check the seating of the pin in the slot on the Xpander. 

Then attach the Xpander onto the lens universal mount, tightening the threaded locking collar firmly hand tight.  Use caution not to cross-thread the fine threads in the universal mount and locking collar.

Then mount the lens, properly supported, on the camera, and verify that the lens properly holds focus on a target 10 feet (3 meters) distant, throughout the zoom range.

No, because there is not enough space. The lens elements
in the rear of the Xpander will collide with the optics in the front of the Extender. If you want to use a 1.4x or 2x Extender with a lens, you must first remove the Xpander, re-install the factory supplied stock PL lens mount on the lens, then attach the Extender. 

No, prime lenses lack the neutral mount that you will find on the rear of Angenieux and Cooke zoom lenses.

First, you need to verify the lens, with the stock factory supplied PL mount installed, holds focus throughout the entire zoom range, when mounted on your camera, and focused on a target 10 feet (3 meters) distant. If it does not hold focus during this test, you will need to have your lens and camera serviced by a qualified service technician.  If the lens holds focus with the factory PL mount installed, then the first thing to look for is a little bit of dirt or grit between the front of the Xpander and the rear of the lens universal mount surface. Both need to be very clean, so that the flange-focal distance will remain correct when you install the Xpander.

Also, be certain that the pin, located in the rear of the lens universal mount, fits into the slot on the front of the Xpander, before tightening the locking collar ring. 

Also, in any situation, all zoom lenses need to be properly supported with sturdy matte-box rods, especially the very heavy Angenieux 24-290 Optimo. If a lens is not properly supported, it can change the carefully calibrated flange-focal distance. 

Yes, by special order.

No. If you were to mount a lens, with an Xpander installed, on a film camera, it would shatter the spinning mirror-shutter. The back end of Xpanders have an engraved warning to not mount them on cameras with a spinning mirror-shutter. 

Extenders have a fixed pre-determined magnification: either 1.4x or 2x, regardless of the lens they are mounted on. They are designed make the lenses more telephoto and are only optimized to cover the original format, eg: Super-35 to Super-35. Xpanders have a magnification specifically tailored to provide sufficient magnification to cover the intended larger sensor size, with the minimum amount of light loss, and have well corrected optical performance. Optica Magnus Xpanders also utilize high quality optics that retain all the performance of the zoom lens.