The Olympus IS-1000 (aka L-1000) is an autofocus 35mm single lens reflex camera with built-in 4× zoom lens. It was the first in Olympus' iS series of so-called 'Zoom Lens Reflex' cameras. The lens is a multi-coated 35-135mm f4.5/5.6 lens with 16 elements in 12 groups and including an ED (Extraordinary Dispersion) objective lens element, providing sharp and contrasty images of a quality approaching that of Nikon prime-lenses. The autofocus is a passive CCD line sensor. A "Power Focus" button allows manual focusing by means of electronic buttons.

This camera and the others in its range have a unique built-in flash, comprised of two flash tubes (the smaller of which provides a series of low-power pulses to reduce red-eye) and a very intelligent TTL flash control system based on distance from the subject rather than on reflected light. This flash system can't be confused by dark subjects on a dark field, light subjects on a light field, etc.

Further, cameras in the early IS-series (IS-1000, IS-2000 and IS-3000) were capable of intelligently combining the built-in flash and the unique G-40 external flash (for example, handling direct fill-flash using the on-board flash unit and bounce flash using the G-40's swivelling/tilting head) - a feature very far ahead of its time and not to be seen until the most recent crop of high-end Digital SLRs.

These cameras featured of course a variety of flash and other shooting programs. Exposure is controlled electronically by a sensor behind a half-transparent mirror of the viewfinder system - full program, aperture-priority and manual modes are available, the camera can be switched between ESP ("Electro Sensitive Pattern"), centre-weighted and spot metering, and exposure can be manually adjusted up and down by up to 4EV. A "portrait" mode allows automatic zooming of the lens to the correct focal length to take head, head-and-shoulders or full body shots once the autofocus locks onto a subject's range.

With its size 117x90x153mm (closed) and its weight of 875g it is of a reasonably compact construction.

The IS-1000 is also known as the IS-1 in the US. It requires DX-coded film canisters, and ISO cannot be set manually. Required batteries are 2x3V CR123A or equivalent.