Guides

How to buy, identify, and use old glass.

Written from the catalog data and the questions collectors actually ask. No filler.

• How to identify a Helios 44-2 variant

  The 58mm f/2 Helios-44 was built for over three decades at three Soviet plants in at least nine versions. Five checks separate them in under a minute.

  September 7, 2026 · 1014 words

• Adapting M42 lenses to Sony E

  M42 to Sony E is the most common vintage adaptation there is. The mechanics are simple; the mistakes are all in adapter choice and aperture pins.

  September 7, 2026 · 1094 words

• Thoriated glass and yellowing: what to know

  Thorium oxide made fast lenses possible before rare-earth glass did. It also made them slightly radioactive and, decades later, yellow. Both are manageable.

  September 7, 2026 · 1032 words

• The vintage lens buying checklist

  Most bad vintage lens purchases fail on one of five faults that a flashlight and two questions would have caught. This is the list, in the order to use it.

  September 7, 2026 · 1180 words

• Swirly bokeh lenses explained

  Swirl is not a special optical formula. It is mechanical vignetting in a fast Double Gauss lens, and once you know that you know how to get more of it.

  September 7, 2026 · 950 words