The 135mm prime is the cheapest good lens in the used market and has been for thirty years. Every SLR system made one, most made several, they were sold in enormous numbers as portrait lenses, and then autofocus arrived and the entire installed base became unwanted. A clean M42 Takumar 135 or a Canon FD 135 costs less than a decent filter. On a crop body it becomes roughly a 200mm equivalent, and that is the focal length where industrial subjects start behaving properly.

I bought into Canon on purpose. Not once — twice. The R8 for full frame, the R100 for the days I want something I won’t cry about dropping. I like Canon’s color science, I like where Canon puts its buttons, and I have defended the RF system in conversations where defending it made me look like a hostage. Nobody tricked me into this mount. I walked in. So understand that what follows isn’t brand tribalism.

The Canon EF 135mm f/2L USM is one of the most respected telephoto primes ever made and one of the few legacy lenses where the secondary market price has declined meaningfully as photographers have migrated to mirrorless systems and RF glass. Used copies trade in the $600–$750 range — less than they commanded five years ago, and substantially less than the optical quality warrants. The Sigma MC-11 adapter, which communicates the EF protocol to Sony E-mount bodies with high fidelity, adds approximately $199.

The 135mm focal length occupies a curious position in the portrait photographer’s arsenal. Long enough to fully compress a face from a comfortable working distance, fast enough at f/1.8 to produce background separation that rivals shorter, wider-aperture alternatives — it is the choice of photographers who have thought carefully about what they actually want rather than what specifications suggest they should want. Sony’s FE 135mm f/1.8 GM is the best lens in this category.

I love fast 135mm lenses—but the Canon RF 135mm f/1.8 L IS USM sits at around $2,300, and I’m not interested in selling a kidney for a lens. I’m also pretty averse to burdening myself with heavy, expensive gear while traveling. So the workaround, at least for how I shoot, is simple: a Canon EF 85mm f/1.8 USM picked up used for about $300, mounted on a crop body. It becomes a kind of “poor man’s 135mm”—a fraction of the cost, easier on the back and shoulder, and, as this image shows, more than capable.