Vivitar 35-70 mm f/3.5-4.8 focus problem

[aleczanussi]

Hi,

I tried to clean this Vivitar lens:

https://www.fotodotti.it/minolta-mc...5-70mm-f-3-5-4-8-in-excellent-conditions.html

I opened it, cleaned it and reassembled it. Then I shot a film to test it and all the photos came out with problems of focus and distorsion around the center (as you can see from some photos I attached).

Could someone explain to me what's the problem here? How can I solve it?

Thanks
Alec

 

[rfaspen]

Very artistic. The lens might have a new specialized use from now on...

Actually, my best guess is one of the elements was replaced "backward" when reassembling. At least I've had similar behavior with other lenses in the past (never a zoom lens, they scare me).

 

[aleczanussi]

Thank you!
In fact I tried now by reversing a lens inside and now it seems working properly! 😉