# Why Chromatic Imaging Matters

## TL;DR

This paper reviews the current state of optical interferometric image reconstruction, emphasizing the importance of chromatic imaging, and demonstrates software capabilities through simulated data to enhance high-angular resolution astrophysical studies.

## Contribution

It provides a comprehensive overview of current chromatic image reconstruction techniques and introduces practical cookbooks for using state-of-the-art software tools.

## Key findings

- Chromatic images can be reconstructed from simulated MATISSE data.
- Regularization functions significantly impact image quality.
- Software like SQUEEZE effectively recovers chromatic images.

## Abstract

During the last two decades, the first generation of beam combiners at the Very Large Telescope Interferometer has proved the importance of optical interferometry for high-angular resolution astrophysical studies in the near- and mid-infrared. With the advent of 4-beam combiners at the VLTI, the u-v coverage per pointing increases significantly, providing an opportunity to use reconstructed images as powerful scientific tools. Therefore, interferometric imaging is already a key feature of the new generation of VLTI instruments, as well as for other interferometric facilities like CHARA and JWST. It is thus imperative to account for the current image reconstruction capabilities and their expected evolutions in the coming years. Here, we present a general overview of the current situation of optical interferometric image reconstruction with a focus on new wavelength-dependent information, highlighting its main advantages and limitations. As an Appendix we include several cookbooks describing the usage and installation of several state-of-the art image reconstruction packages. To illustrate the current capabilities of the software available to the community, we recovered chromatic images, from simulated MATISSE data, using the MCMC software SQUEEZE. With these images, we aim at showing the importance of selecting good regularization functions and their impact on the reconstruction.