Sony's affordable full-frame DSLR — the A850, ~24.6MP, pentaprism OVF, in-body stabilisation, 2009.
The Sony A850 is a full-frame professional digital SLR announced in 2009, part of Sony's Alpha A-mount line built on the Minolta/Konica Minolta autofocus system. It was launched as a more affordable sibling to the flagship A900, sharing much of that body's specification while sitting a step below it, and it gave A-mount users a lower-cost route to a 35mm-format sensor.
It is a conventional DSLR with an optical pentaprism viewfinder offering roughly full-frame coverage and a moving reflex mirror. It uses the Sony A (Alpha) bayonet mount and accepts A-mount and adapted Minolta AF lenses, including the Zeiss and G-series optics. The body has a full-frame sensor of about 24.6 megapixels and sensor-shift SteadyShot INSIDE stabilisation that works with any lens. It has no video recording and takes Memory Stick and CompactFlash cards.
The A850 suits landscape, portrait and studio work where the full-frame sensor and high resolution matter, and where in-body stabilisation adds value to a large lens collection. Its bright optical finder and robust build serve considered, tripod-based shooting well, though its contrast-detect-free autofocus and lack of video reflect its stills-first, late-2000s design.
When buying used, check the shutter count against its rated life given the body's professional duty cycle, inspect the full-frame sensor closely for dust and marks, and test the screen for dead pixels. Confirm the CF and Memory Stick doors and battery door latch securely, listen for IBIS rattle, and check the weather seals and grip rubber. NP-FM500H batteries are available aftermarket; the A850 remains valued as an affordable full-frame A-mount body.