DK-Optic Impastolite 2-inch(51mm) f1.5 m
A Tribute to an Optical Legend
The mid-20th century British 50mm f/1.5 (widely known as the legendary Septac) remains one of the rarest and most mythologized ultra-fast lenses in history. It represented the era’s absolute pinnacle of light-gathering capabilities and unique, painterly rendering. Its vintage atmosphere and signature look are just as highly sought after today as they were decades ago. Driven by pure passion, DK-Optic has flawlessly resurrected this masterpiece, combining its vintage soul with the extreme precision of modern industrial manufacturing.
Authentic Optical Recreation
Rather than injecting clinical modern corrections, we engineered a 1:1 true-to-original restoration. By refusing modern optical additives and utilizing a specially formulated vintage-style amber coating, we have faithfully preserved the distinctive, evocative flavor of the original glass.
Signature Rendering & Character
Rejecting the sterile, dry perfection of modern optics. Wide open at f/1.5, the Impastolite delivers a mesmerizing "Glow" alongside its signature, highly painterly, swirly bokeh. Under backlit conditions, it produces rich, cascading "peacock feather" flares. Yet, as you stop down the aperture, the image rapidly transitions, revealing exceptional contrast and high resolving power.
Cinematic-Grade Artisanal Construction
Leveraging our high-end cinema lens production capabilities, every mechanical and optical component is designed and hand-assembled in our bespoke optical workshop.
Black Paint & Mechanics:
The main exterior barrel is crafted from high-strength 7075 aerospace-grade aluminum to significantly reduce weight. The core focusing helicoid and aperture mechanics are CNC 5-axis machined from aerospace-grade brass, providing an unmatched, buttery-smooth tactile feel.
Vintage Optics:
The internal elements are crafted from decades-old New Old Stock (NOS) optical glass, perfectly replicating the exact refractive index and classic characteristics of the original materials.
Specifications
Focal Length: 51mm (2 inch)
Format Coverage: 135 Full Frame (24x36mm)
Optical Design: 7 Elements in 5 Groups
Minimum Focusing Distance: 0.7m (Perfectly coupled for rangefinder systems)
Aperture Control: Manual preset (Dampened and calibrated to cinema-grade standards)
Aperture Range: f/1.5 – f/11
Aperture Blades: 18 blades (Ensuring a perfectly circular bokeh at all stops)
Lens Mount: Native Leica M-Mount
Filter Thread: 43mm (Lens Body) / 46mm (Lens Hood)
Lens Hood: Detachable threaded metal hood
Length (Mounted on camera): 46mm
Maximum Diameter: 54mm
Weight: 179g (Brass/Aluminum hybrid construction, excluding caps)
In the Box
DK-Optic Impastolite 2-inch f/1.5 Lens
Precision-machined Full Metal Front Cap
Vintage-style Metal Lens Hood
Custom DK-Optic Bamboo Presentation Box
Certificate of Authenticity with Individual Serial Number
1-Year Official DK-Optic Warranty
Shipping & Logistics
Global Shipping Hub: China (Shenzhen / Hong Kong)
Please Note: Because DK-Optic adheres to the highest standards of manual assembly and meticulous optical calibration, the initial pre-order batch and special edition kits may require a slightly longer production cycle. Standard orders are shipped via DHL, UPS, or FedEx, with an estimated global transit time of 7–14 business days. In the event of production-related delays, our dedicated customer service team will proactively contact you via email.