This Pentax Super Takumar 105mm f/2.8 is a decent lens stopped down a wee bit and you can’t go wrong with it if you find a good deal. Being a M42 mount you can use this lens on some Digital camera bodies with an Ebay M42 Adapter. Also split focus screens from Ebay make focusing a lot easier!
There are some extremely amazing lenses out there and this Pentax-A 100mm f/2.8 SMC Macro is a prime example of mechanical and optical perfection. However this is a hard to find lens and still costs just as much as a newer auto focus 100mm macro lens even today. For perfect focus I would check Ebay to see if you can get a split focus screen for your body.
This was a good showdown with the Sigma 85mm f/1.4 EX Vs. Bell & Howell 85mm f/1.4. Both lenses are extremely good but both give options for your needs. In the end if you need auto focus go with the Sigma 85mm f/1.4 EX DG HSM but if you are on a budget and can manage a manual lens, it seems the Bell & Howell 85mm f/1.4 Aspherical IF MC has a slight optical edge. You can also look on Ebay to see if there are split focus screens that will help you manual focus the Bell & Howell lens.
This Sigma 85mm f/1.4 EX DG HSM is a fantastic lens for the price with quick focus, sharp photos and really nice bokeh producing some really nice portraits. For a while I went crazy telling everyone around me to go out and buy one because they are so good.
This Bell & Howell 85mm f/1.4 Aspherical IF MC is a fantastic lens for the price if you don’t mind manual focusing. I would get a split focus screen from Ebay for your DSLR to make focusing easier. This lens comes in many names other like Samyang, Rokinon, Bower, and Pro Optic but are all made by Samyang so look around Adorama or Ebay for deals under the other names.