What is RTI (Reflectance Transformation Imaging)?

RTI (Reflectance Transformation Imaging) is a relightable imaging technique. It combines multiple captures of an object under controlled multi-directional lighting to produce a single digital image in which light direction can be changed afterwards, revealing relief, marks and material.

An RTI dome is an acquisition device with multiple light sources arranged in a hemisphere around the object. It automates multi-angle capture and ensures the reproducibility needed for usable RTI. Mercurio Imaging makes two portable domes: ASTERIA (up to about 15 cm) and CEOS (up to about 20 cm).

What is RTI used for?

RTI is used to study an object’s surface: micro-relief invisible to the naked eye, worn inscriptions, tool traces, signatures, restoration marks, conservation states. It supports expertise, documentation, state comparison and remote scientific sharing in heritage, research, jewellery, watchmaking and the arts.

How long does an RTI acquisition take?

On our studio and field devices, an RTI acquisition takes about 10 minutes per object, around 6 objects per hour, with 105 light sources and a 24-megapixel reference capture. Pace adjusts to object complexity and protocol.

What is the difference between RTI and 3D photogrammetry?

Photogrammetry produces a geometric 3D model. RTI does not produce strict 3D geometry but an image modelling surface light response, enabling interactive relighting. RTI is faster to produce, lighter to share online and especially suited to flat or low-relief surfaces.

Can RTI be used in the field?

Yes. Mercurio Imaging ASTERIA and CEOS RTI domes are portable, delivered in transport cases, and designed for studio, museum storage, laboratory, conservation workshop or on-site use (excavations, heritage sites).