I have a Pentax K-x and it's pretty versatile as far as different lenses that it can use and I've been looking on ebay for some older manual focus lenses but I'm unsure exactly what is good and what isn't. I know the 50mm lenses are all generally the same and there isn't a huge difference between each version. I saw a Pentax Super Takumar 85mm F1.9....the condition of the lens looks excellent and I'm pretty sure I can use the cameras auto settings with this one but wasn't sure if this was a good one or not.... What other lenses should I look for? I don't have a ton to spend but all I have is the kit lens...which is decent but I'd like something a little better. I mainly do portraits and landscapes so the 85mm if it's a good lens...would be perfect for me.