UPDATE: Both lenses are now sold out with no backorders available. Deal is expired. Congrats to all readers who got in on this crazy deal! Nikon and Pentax mounts are still available.
The Irix 15mm f/2.4 Firefly and Irix 15mm f/2.4 Blackstone are third party lenses, quietly announced in 2016, to many decent reviews (including The Digital Picture and Northlight Images). The overall conclusion was that at the regular prices of $475 and $575, you get a decent value lens for the price you pay.
Today, Amazon has both lenses for a whopping 70% off. Click “70% off 1 item(s)”, then “Redeem”, prior to adding the item to your cart. You’ll see the discount at checkout.
Note the lenses are sold by Irix USA, but fulfilled by Amazon. The Irix 15mm f/2.4 Firefly is $142.48 and the Irix 15mm f/2.4 Blackstone is $172.48. A total steal for lenses of this quality and construction!
The difference between the Firefly and the Blackstone appears to be just build quality (with the Blackstone sporting an all-metal build exterior). Optically, the two lenses look to be the same. Please note that these are manual-focus lenses, but support electronic focus confirmation.
We can’t imagine this deal will last very long. It appears to be some sort of clear-out.
