Every published object is open access◆PHOTARCH — an open photo archive for museums, archives and collections◆A measurable archive◆Comparable objects, from any collection◆The scale is in the file, not on the picture◆One method, the same light, every time◆Every object at its true size◆Every published object is open access◆PHOTARCH — an open photo archive for museums, archives and collections◆A measurable archive◆Comparable objects, from any collection◆The scale is in the file, not on the picture◆One method, the same light, every time◆Every object at its true size◆

Guides

The method describes what a PHOTARCH photograph is and why. These guides describe how to make one: what to set up, in which order, and what to check before a picture leaves the studio. Each answers one question, and each links back to the reasons.

How to photograph objects for archives and collections

The whole procedure, step by step: light, ground, colour card, exposure, angles, scale, grade and export.

Scale in object photography

Why a ruler beside the object measures the ruler, how far a few millimetres of height throw a measurement, and how to carry a measured scale inside the file.

Bit depth for archival photography

What 8, 12, 14 and 16 bits mean, what cameras actually record, why files come in 8 or 16 bits, and how to make the most of what the camera gives.

Choosing a camera

Pixels per millimetre at the object rather than megapixels, when sensor size matters, raw and the bits it records, and a phone or a dedicated camera.

Choosing a lens

Macro or normal lens, focal length and working distance, perspective, distortion, and where aperture stops adding depth and starts costing sharpness.

Lighting objects

One key light from the upper left, the shadow kept as information, a fill that softens without removing, and metal, glass and glaze.

A white background

Why white rather than grey, how to expose the ground without clipping the object, why the shadow stays, and why a photograph on white is not a cut-out.

Colour accuracy and the ColorChecker

The card in every sitting, white balance, ΔE2000 in plain words, colour spaces and profiles, and what a reference chart can and cannot do.

File formats for archival photography

Raw, DNG, TIFF and JPEG: the camera original, the preservation master and the access copy, and what to keep and what to publish.

Measuring objects from photographs

Millimetres per pixel, where the scale comes from, how accurate a measurement is, the one-plane limit, and why the scale belongs in the file.