Something slightly counterintuitive happens when you look at the Tamron 35–100mm f/2.8 through the lens of crop-sensor photography. On paper it’s a full-frame zoom sitting awkwardly between two traditional categories. In practice, though, its design echoes a lens many APS-C shooters have wanted for years but rarely get: a lightweight 50–150mm f/2.8 equivalent. Take the focal range first. On a full-frame camera the Tamron spans 35mm to 100mm. That covers the classic documentary and portrait focal lengths—35mm environmental shots, 50mm standard perspective, 85mm portraits, and 100mm tighter headshots.

Portrait photographers run into this comparison sooner or later because on paper the math looks simple. An 85mm lens on an APS-C crop camera produces roughly the same field of view as a 135mm lens on a full-frame body. So framing the subject — head and shoulders portrait for example — ends up looking almost identical. Stand at roughly the same distance, frame the same composition, and the scene inside the frame feels very similar.

Sigma has announced a groundbreaking addition to its celebrated Art series: the Sigma 135mm F1.4 DG | Art, the world’s first autofocus 135mm F1.4 prime lens designed for full-frame mirrorless cameras. Scheduled for release in late September 2025 at a retail price of $1,899 USD, this lens is set to redefine professional portraiture and establish new benchmarks for optical excellence. The 135mm focal length has long been a favorite among portrait photographers for its natural compression and immersive depth.