Tamron's budget Adaptall-2 standard zoom — the basic 28-70mm f/3.5-4.5.
The Tamron 28-70mm f/3.5-4.5 in Adaptall-2 mount is a basic standard zoom with universal mount capability. The 28-70mm covers the essential standard range. Variable aperture. The Adaptall-2 system enables cross-system use. A basic Tamron zoom without the SP tier quality — functional at minimum specification.
Basic Tamron optical quality — below SP tier. Sharpness acceptable stopped down. Variable aperture. The 28-70mm covers standard to short telephoto. The Adaptall-2 versatility is the main feature. Build quality is functional but below SP. A basic zoom for photographers who value cross-system compatibility at minimum cost.
Adaptall-2 universal mount — adapter required. Filter thread varies. Weight varies. Basic build. The Adaptall-2 enables multi-system use. Not SP quality. Ensure correct mount adapter is included or available for your camera system.
Very cheap. Basic quality below SP. The Adaptall-2 versatility is the sole advantage. The SP 28-80mm (ID 4593) is preferred for quality. Only at near-zero prices. Ensure adapter included.