A Brief History of Optical Formulas in the Early 20th Century and Review of the Helios 40-2 Lens

Anyone diving through the nichiest camera lenses on the market is bound to have come across the Helios 44-2 at some point. Intrigued, they might find it and buy a version of it on eBay for $30 USD and receive it in the mail a month later from the Ukraine. Any further reading will reveal its initial posturing in the 1960’s, and a host of other M42 mount lenses able to purchase from the same anonymous seller. Not a whole lot outside of those modern details are available, however.

To be perfectl...