DUTO Rolleiflex 1 is a classic soft-focus (diffusion) filter

The DUTO Rolleiflex 1 is a classic soft-focus (diffusion) filter manufactured in Germany specifically for Rolleiflex and Rolleicord twin-lens reflex (TLR) cameras. Designed to create artistic, dromerig (dreamlike) effects, it remains a sought-after accessory for vintage photography enthusiasts.  Key Features & Design Optical Effect: The filter uses a plane-parallel glass disc with concentric circles etched into the surface. Light passing through the flat areas creates a sharp “basic image,” while light hitting the grooves is deflected, producing a characteristic halo effect and soft contours around highlights. Intensity: The “1” designation indicates a greater soft-focus effect compared to the “0” version, making it ideal for soft lighting conditions and romantic portraiture. Build Quality: “Made in Germany” by Franke & Heidecke (Rollei), these filters often come in their original branded boxes, which adds significant value for collectors.  Technical Specifications Exposure Factor (approx. 2x): A filter factor of 2x means you must increase your exposure by one full f-stop. For example, if your light meter suggests 1/500s, you should use 1/250s with the filter attached. Mounting: Typically available in Bayonet I (Bay 1) for standard 75mm f/3.5 lenses, though “push-on” versions also exist for earlier models.  Performance Tips Aperture Sensitivity: The soft-focus effect is most pronounced at wide apertures (e.g., f/3.5). Stopping down (e.g., beyond f/5.6 or f/8) will gradually reduce the diffusion effect until the image appears standard. Backlighting: This filter excels in backlit subjects, where it enhances the “plastic, sunny character” of the light by emphasizing halos. Previewing: You can preview the exact effect by placing the filter over the finder lens before moving it to the taking lens for the actual exposure.  Like this:Like Loading… Related