Sigma Zoom 28-70 f3.5-4 UC
Launched 1989

One of the most significant focal lengths in any lens manufacturer’s arsenal, the 24/28-70mm range is a hotly contested area and has been for a very long time. In 1989, Sigma launched their Ultra Compact 28-70mm f3.5-4.

Here is the press release, without editing, from February 10th 1989:

“This lens is the world’s smallest as a 28-70mm zoom lens. This ultra compact standard zoom has special features of ‘Nice touch and scratch free finish’ of the lens barrel. It uses a new type of painting for the finish of lens barrel, which creates a special effect of softer, nicer feeling than an ordinary painting or anodizing when you grasp the lens.

Also it has stronger resistance against a scratch than an ordinary finish.

Hood for this lens is a one-touch mounting system onto the bayonet mount of outside lens barrel. It keeps same lengh of the shade in the entire range of zooming. Ordinary zoom lenses do not have such merit. For example, in the range of telephoto, hood becomes shorter.”

Specifications
Focal Length 28-70mm
Lens Construction 11 elements in 5 groups
Maximum Aperture ƒ3.5-4
Minimum Aperture ƒ22-27
Field of View 75-34°
Minimum Focus Distance 0.5m
Number of blades 7
Maximum Magnification 1:6.15
Zooming System Rotary
Filter Size 52mm
Diameter 64mm (max.)
Length 63.5mm
Weight 320g
SRP at launch: £110-140
Available Mounts: AF: Canon, Nikon, Minolta, Pentax, Sigma

MF Nikon, Canon, Minolta, Pentax, Olympus, Ricoh, Yashica