Vivitar 2x teleconverter

I bought this on Ebay about four years ago but at the time I wasn't happy with the sharpness of the results so it has stayed in the cupboard, until now. I decided to experiment with it on the 100mm macro handheld in the garden and the last two with a HD DFA 150-450mm on a tripod at 450mm from an upstairs window; the results aren't anything spectacular or even particularly good but there is a really nice dreamy quality to them which I could explore more. All manual focus of course but the contacts on the mount meant that I could use a semi-automatic exposure. I have done some basic post processing and the no cropping other than reducing the sides to a square.















Does anyone else have one of these and if so how do you find it?

I have had a vivitar 2x macro KA teleconverter for decades as I bought it new years ago for use with my ME super and superprogram. I have always enjoyed it and yes the results were never tack sharp across the whole frame but were very artistic and have recently dusted it off and plan to use it both on my ME's and my K s2.