Sony A450 has a Sony/Minolta Alpha lens mount and currently there are 143 native lenses available for this mount.
The latest released lenses that are compatible with the A450 are the Lensbaby Sol 45 DSLR, the Venus 105mm F2 and the Lensbaby Burnside 35.
A450 also has a sensor based image stabilization system which means that all of these lenses will be stabilized when used on the A450.
Since Sony A450 has a APS-C sensor, it has a focal length multiplier of 1.5× so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on A450.
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Sony A450 Lenses with Image Stabilization
Sony A450 Lenses with Weather Sealings