. > so really this is what i am asking > as i have the following > tamron 80-200mm 2.8 adaptall > pentax fa 300mm 4.5 > sigma 400mm 5.6 macro > Would there be any benifit replacing them with or adding > a tamron 300mm 2.8 or pentax 200mm fa 2.8 or 400mm f4.
Based on what your saying you should sell your 300 & 400 and buy the Tamron 2.8 300 and a 1.4X TC which give you a 420 F4. The Tamron 80-200 is so good you wouldnt be gaining much buy getting a 200 prime. JCO
