Local Filtering Fundamentally Against Wide Spectrum

TL;DR

This paper critiques the fundamental flaws in a 3D Fourier filtering method used for atomic-resolution imaging of nanoparticles, emphasizing the limitations of local filtering techniques against a wide spectrum of data.

Contribution

The paper provides an in-depth analysis of the methodological flaws in local filtering approaches for 3D atomic imaging, arguing they are fundamentally limited against wide spectral data.

Findings

Identifies fundamental flaws in local filtering methods.

Argues local filtering cannot effectively handle wide spectral data.

Provides a detailed critique of previous 3D imaging techniques.

Abstract

Chen et al. (1) applied three-dimensional (3D) Fourier filtering together with equal-slope tomographic reconstruction for an observation of nearly all the atoms in a multiply twinned platinum nanoparticle. However, their methodology suffers from fundamental methodological flaws, as initially brought up by a recent Communications Arising (2) and now analyzed in-depth in this report written on June 20, 2014. The authors of (1) read this report and wrote a reply containing 5 points. While we have solid reasons to disagree with their points, we will not include our responses here, and will address their first two points using Nature's online commenting facility. References 1. Chen, C.C., et al., Three-dimensional imaging of dislocations in a nanoparticle at atomic resolution. Nature 496(7443):74-79, 2013 2. Rez, P. and M.M.J. Treacy, Three-dimensional imaging of dislocations. Nature 503(E1):74-79, 2013