Using medium-format lenses on a full-frame A-mount body like the Sony Alpha A99 is a niche but very enjoyable setup if you like manual focus, unusual rendering, and superb central sharpness. The key things are image circle coverage, adaptability to A-mount (the lenses mentioned below would need ro be tested on the A99 or other Sony camera before purchase to ensure they can be succesafully adapted to work on this particular camera – I haven’t been able to do this yet) manual focusing feel, and optical character.
The easiest and most rewarding systems to adapt are usually Mamiya 645, Pentax 67, and Hasselblad V lenses. Many photographers report that medium-format lenses on Sony bodies give very clean edges and strong contrast because the full-frame sensor only uses the center “sweet spot” of the larger image circle. �
Best overall portrait lens
Pentax 67 SMC 105mm f/2.4
£315.60 • eBay.
This is probably the most famous adapted medium-format lens ever made. On the A99 it gives a gorgeous portrait look with very smooth transitions and a “large format” feel that many people still chase digitally. Manual focus only, large, and heavy — but magical for portraits and astronomy landscape work.
Best value standard lens.
Mamiya 645 80mm f/2.8 N • £211.15.
Affordable, sharp, and easy to adapt with excellent central sharpness and classic medium-format rendering.
A very sensible choice for starting out. These are inexpensive compared with Hasselblad or Pentax 67 glass, and adapters are widely available. Excellent for portraits, landscapes, and experimental astrophotography.
Best landscape/wide option.
Mamiya Sekor 45mm f/2.8 • £708.00.
One of the best adapted medium-format wide lenses for landscapes and architectural work on the A99.
This gives you a moderately wide field of view on full frame with excellent edge quality. A very good match if you enjoy wide-field night sky photography.
Best Zeiss rendering.
Zeiss Distagon T* 50mm f/4 for Hasselblad V • £3,099.00
Classic Zeiss microcontrast and color with exceptional build quality and superb landscape performance.
If you like the Zeiss “pop” and color separation, Hasselblad V Zeiss lenses are beautiful on Sony bodies. They are slower and expensive, but optically superb.