Duofold RF
Well-known
I asked Grok:
The Helios-103 53mm f/1.8 is not directly derived from a Leica lens, though some vintage lens enthusiasts claim similarities to the Leica Summicron.
Most Helios lenses, like the famous Helios-44 series, are copies or derivatives of Carl Zeiss designs (specifically the Biotar formula, a Double-Gauss type). The Helios-103, produced by the Arsenal factory in Ukraine for Contax/Kiev rangefinder cameras starting around 1980, follows a similar Double-Gauss optical scheme (6 elements in 4 groups) and is often described as based on the Zeiss Biotar concept, symmetrical unlike Sonnar designs.
However, community discussions (e.g., on Reddit’s r/VintageLenses) cite Leica expert Malcolm Taylor identifying its optical cross-section as closely matching a late-1960s Leica Summicron 50mm f/2 (a Double-Gauss design). Some speculate the Soviets may have copied or adapted it without license, recalculating for f/1.8 aperture, 53mm focal length (to suit the Contax/Kiev register), and available Soviet glass types. This remains anecdotal and unconfirmed by official sources—most references tie Helios lenses broadly to post-WWII Zeiss influences rather than Leica.
In summary: It’s a modern Soviet Double-Gauss normal lens with high sharpness (reported 55/28 lines/mm center/edge), but its primary lineage is Zeiss-inspired, with possible unverified parallels to the Summicron.
The Helios-103 53mm f/1.8 is not directly derived from a Leica lens, though some vintage lens enthusiasts claim similarities to the Leica Summicron.
Most Helios lenses, like the famous Helios-44 series, are copies or derivatives of Carl Zeiss designs (specifically the Biotar formula, a Double-Gauss type). The Helios-103, produced by the Arsenal factory in Ukraine for Contax/Kiev rangefinder cameras starting around 1980, follows a similar Double-Gauss optical scheme (6 elements in 4 groups) and is often described as based on the Zeiss Biotar concept, symmetrical unlike Sonnar designs.
However, community discussions (e.g., on Reddit’s r/VintageLenses) cite Leica expert Malcolm Taylor identifying its optical cross-section as closely matching a late-1960s Leica Summicron 50mm f/2 (a Double-Gauss design). Some speculate the Soviets may have copied or adapted it without license, recalculating for f/1.8 aperture, 53mm focal length (to suit the Contax/Kiev register), and available Soviet glass types. This remains anecdotal and unconfirmed by official sources—most references tie Helios lenses broadly to post-WWII Zeiss influences rather than Leica.
In summary: It’s a modern Soviet Double-Gauss normal lens with high sharpness (reported 55/28 lines/mm center/edge), but its primary lineage is Zeiss-inspired, with possible unverified parallels to the Summicron.
