Tamron SP 80-200 mm f/ 2.8 LD Adaptall-2 model 30A Lens

Sharp wide open.

Fast constant f/2.8 aperture across the focal range.

One handed focus/focal operation.

Not expensive (250 euros mine).

Weaknesses:

Weight (1.3Kg), monopod and tripod ring recommended.

Some cromatic aberrations.

Front element rotates during focusing.

Difficult to find.

Comments:

This lens is build like a tank, all made of metal, it weights 1.3Kg. I recommend to use a tripod or monopod with the proper tripod ring.

I like this lens a lot, I use it mainly for indoor sports like gimnastics where f/2.8 is a must have when your camera cannot use ISO 3200 and over.

Having an unique focus/focal ring dessign makes this lens very well suited for sports ussage in one handed operation, actual designs with two rings are a mess when used manually as you need two hands in order to move quickly the focal and focus rings.

Optically this lens is incredible for its age, it cannot compete against current Canon "L" lenses that cover the same focal range, but works very well, has good contrast and sharpnes starting wide open. If Tamron had put another LD glass inside this beast...

I also used this lens with Tamrons Adaptall teleconverters:

With the x1.4 (model 140F)  you will get very good results and only will loose 1 stop.

With the x2 teleconverter the results are not good in my opinion as the chromatic aberrations are also augmented, you can close one stop or two, but the aberrations are still present.

The biggest mess is its weight.

But you know, if you want to get good pictures... weight is a secondary factor.