Specialty lens with extreme focal length and minimal throw distance — projects large images from close range. Essential for virtual production and LED volume work.
Anyone working in an LED volume with only three meters of space to the back wall quickly learns to appreciate UST optics. Ultra Short Throw — these are lenses that project gigantic images onto the screen from the shortest distance. While standard projectors still need at least five to seven meters of distance to create a 4x2 meter image, UST lenses achieve the same from one and a half to two meters. The focal length is typically between 4 and 8 mm — extreme wide-angle, therefore, combined with special lens designs that minimize distortion while preserving light intensity.
On set, this means: You position the camera closer to the LED wall, saving valuable space for actors, rigs, and movement. This is crucial in Virtual Production — every centimeter counts in these volumes. The projector engine is literally located behind the optics, not behind it as in conventional systems. However, this requires precision in matching: the distance between the camera and the projector must be calibrated to the millimeter, otherwise, a parallax error will occur, which you will immediately see in the image. This is not just a visual problem — it destroys the entire in-camera VFX illusion.
Practically, this also means: UST optics are expensive, specialized, and not interchangeable like standard zooms. You need the right UST for the planned resolution and image size. For 4K content with high sampling, we often work with projected resolutions of 2K or higher per projector. The depth of field is generally greater with such short focal lengths — an advantage for tracking and LED calibration, but precise focus work is still required because the tolerances are small. Camera shake or minimal camera movements become visible due to the extreme wide-angle perspective.
You can also recognize UST projectors by their compact, almost cube-shaped housing and very short lens tubes. Manufacturers like Optoma, Panasonic, or Epson now have specialized UST models for broadcast and production — not just for events. In virtual sets, UST optics are the standard today, not the exception. Together with real-time engine software (Unreal, Unity) and LED screens, they enable compact, highly flexible production where you can shoot scenes variably on a smaller scale.