The Sinar X is a 4x5 large-format monorail view camera made by the Swiss manufacturer Sinar, designed for studio and architectural work where full movements (rise, fall, shift, swing and tilt) are required. It sits within Sinar's modular monorail system, allowing components to be swapped between bodies and accessories.

With only a single tracked UK auction hammer result on file — £576 in April 2018 — the saleroom data for the Sinar X is extremely thin, so any sense of what one is worth today rests on that lone wholesale figure rather than a true range. As of 2026, buyers asking how much a Sinar X sells for at auction should treat that £580 hammer as indicative only; condition of the bellows, rail and standards has a large effect on price, and a complete outfit with film holders and lens boards typically commands more than a bare body.