I cannot say if the lens you have is good or not, but Konica-Minolta's camera assets were transferred to Sony. One thing to note is that most DSLR camera sensors are smaller than a 35mm frame, thus introducing a "crop factor." This means that the Promaster 28-200mm lens on a Sony DSLR will be equivalent to a 42-300mm lens.
I am trying to clean out extra stuff and am looking at a promaster 28-200mm lens on a minolta maxxum 550si film camera. Is the lens worth keeping? Could it be used on a digital camera? I read some of the past posts on the topic but they were dated 2007. I wonder if anyone has any recent experience with this issue. thanks.

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