Lens Lab
    Promaster AF 28-300 mm f/ 3.5-6.3 XR EDO LD Aspherical (IF) Macro Spectrum 7
    Promaster AF 28-300 mm f/ 3.5-6.3 XR EDO LD Aspherical (IF) Macro Spectrum 7

    Promaster AF 28-300 mm f/ 3.5-6.3 XR EDO LD Aspherical (IF) Macro Spectrum 7

    28–300mm · f/3.5–6.3

    Overview

    The Promaster AF 28-300mm f/3.5-6.3 XR EDO LD Aspherical (IF) Macro Spectrum 7 (rebadged Tamron) is a compact, lightweight superzoom. Optical performance shows high chromatic aberration at wide and telephoto ends, improving stopped down. Distortion is moderate: barrel at wide, pincushion at tele. True focal length at 300mm is ~280mm, and effective aperture may be f/7.1. Build is typical for consumer zooms; AF is adequate in bright light but struggles in low light at 300mm. Best suited for casual users wanting a single-lens solution for daylight shooting, especially on full-frame or film cameras.