Greetings,
Most of the time, I would not attempt to use a legacy zoom lens with a 4/3rds camera because zooms are apt to have more problems on a dSLR since they have more elements. However, I was experimenting with lunar photography and had an opportunity to try this Vivitar Series 1 zoom. For those who aren't familiar, the "Series 1" lenses were Vivitar's very best and were marketed as "professional" lenses. This lens had an OM mount and I used the Olympus OM-to-4/3rds adapter.
The focal length is changed by sliding the focus barrel forward and backward. Here is a view of the lens fully extended. I've never cared for this type of zoom because the barrel will sometimes move when you don't want it to. For example, when you rotate it to focus or when you hold the camera upward to photograph something overhead.
I don't have any daytime shots to show. When I tested this lens my primary interest was shooting the moon.Here is my best shot with the lens fully extended to 500mm. I think the aperture was f8.0. The photo has been cropped and was moderately sharpened (note: I couldn't locate the original unsharpened photo---I didn't anticipate that I would be writing this rewiew when I took the shot) .
I also tried using the lens with the Olympus Zuiko Digital EC-14 teleconverter but the results were very disappointing due to softness and chromatic aberrations (CA).
Pros
This is an outstanding multicoated 100-500mm super-telephoto macro zoom for film photography.
Mechanical - All metal lens body with large rubber-wrapped focus barrel.
Optics - Nice zoom range and macro capability, making this a very versatile lens.
Cons
Mechanical - The sliding zoom is a pain. When extended, it won't hold its position if the lens is pointed upward. The rotating tripod mount cannot be removed and it is useless if you have an HLD-2 battery grip on your E-1 (like I do) because it is located way back at the rear of the lens where there is not much clearance.
Optics - The lens produces moderately soft pictures on a 4/3rds camera. There is also visible, but mild, CA. I shot some outdoor daytime shots and none of them could compare to the sharpness of the Zuiko Digital lenses (I can't share them because none were saved). Because of the softness and mild CA, I can't recommend this lens. But it isn't so terrible that I would rate it "bad". So it receives a "mediocre" rating.