The essayistic device in film often brings together two temporalities of film creation: the present of the filmed image and the present of the editing process. Through the interaction of both moments, provoked by the critical revision of the raw material and its possibilities of montage, the essay film is constructed through the filmmaker’s exploration of the filmic apparatus, thus revealing film forms as a way of producing and disseminating knowledge. The essay film, therefore, subverts a common theoretical practice: thought is no longer assumed as a procedure for unveiling an image, but it is rather produced by film forms. We claim that the essay film, as a research methodology and a theoretical approximation to film informed by practice, must be unfolded through creative gestures, this is to say, images and sounds that present an audiovisual synthesis of the conscious and intuitive work that both precedes and is synchronic to the moments of filming and editing. This article addresses the essay film through a comparative association of several filmmakers that express and study both concrete and abstract issues of cinema and filmmaking through their own creative practices.

In transmission electron microscopy (TEM), electrons are nowadays traditionally detected using a charged-coupled device (CCD) in the case of indirect detection trough a scintillator via an optical fiber coupling, or more recently using complementary metal-oxide semiconductor (CMOS) with direct detection. In both cases the "true" image is unfortunately degraded by the non-ideal point spread function (PSF) of the detector leading to a blurring of the signal and the addition of stochastic noise components such as dark-current noise or readout-noise.Detector performances can be assessed by the measurement of the effective gain, the conversion factor, the point spread or modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) [1,2]. Defective pixels can also be listed as outliers in a lookup table. On-site characterization of the detector performance can be useful for several reasons. First of all, it allows us to verify the specifications provided by the manufacturers of the devices, to compare the relative performance of different detectors and to estimate their degradation over time. Secondly it can help to optimize the data acquisition strategy for a given problem, for instance low dose experiments or high-resolution imaging. Finally this information can be used as prior knowledge for data processing algorithms.In this work energy filtered transmission electron microscopy (EFTEM) has been used to illustrate the benefits of the knowledge of the characteristics of the detection system. EFTEM is useful technique to investigate the chemistry of materials at the nanometric scale. However such a technique is often limited by long exposition times and weak signals, in particular at high-energy losses. Images corresponding to different energy losses are sequentially recorded on the camera device, resulting in a 3-dimensional dataset {x, y, E} for which each image plane {x, y} is convolved with the PSF of the camera and each spectrum {E} with the resolution response function of the spectrometer.This works aims in a first step to measure the noise and contrast transfer characteristics of the Gatan US1000 camera used in our JEOL 2200FS TEM microscope in order to improve our EFTEM acquisitions. The recently developed silhouette method [2] is used for the determination of the CCD MTF. In a seconds step this works tries to apply multivariate statistical approaches such as principal component analysis [3,4] and algorithms based on statistics in order to perform the denoising of the data as well as the improvement of its spatial or spectral resolution by deconvolution techniques. The prior knowledge of the (quasi-poissonian) noise model and the MTF of the camera are embedded in the deconvolution algorithms in order to perform the regularization of the solutions in a realistic way.The data processing procedure is demonstrated on a simulated dataset providing a ground truth for exploring the applications, limits and eventual pitfalls of the algorithms under known noise levels an...

fue allí, en el curso 1995/96, cuando conocimos a José Luis Guerin, que nos dio clases de guion. En aquel momento estaba acabando Tren de sombras (1997), una película rodada en 35mm que hizo para conmemorar el centenario del cine. Después, a finales de los 90, Abel cursó el Máster de Documental de Creación de la UPF y entró en el equipo de rodaje de En construcción. Por este motivo, nos proponemos hablar desde ese contexto formativo, y hacerlo en primera persona, para dejar nuestro testimonio como antiguos alumnos de Guerin. Además, dado el espacio de esta intervención, donde muchos de vosotros vais a ser profesores, pensamos que es importante remarcar que En construcción fue una película pedagógica, un proceso formativo, un aprendizaje para aquellos alumnos del Máster de Documental de Creación de la UPF que formaron el equipo, como Abel y otros compañeros.Podríamos empezar así por mencionar el método comparativo que empleaba en clase para pensar el cine, proyectando fragmentos y asociando imágenes de películas, generando correspondencias entre ellas. Para pensar En construcción, por ello, puede ser relevante verla como un proceso de montaje asociativo o poético, pues no se estructura tanto desde su linealidad o continuidad, como desde los motivos o rimaspensemos en las ventanas o las chimeneas-que la van hilvanando. Cuando los estudiantes empiezan a montar suelen partir de lo consecutivo, piensan el plano A en relación al B, el B en relación al C, mientras que en lo asociativo, tal como Guerin nos mostraba, el plano A se piensa y articula también en relación a X o Z, es decir, a todos los demás, en un conjunto orgánico.Guerin era un gran transmisor que nos enseñaba fragmentos de películas que no habíamos visto, cine que empezábamos a imaginar o soñar, ya que en aquella épocajusto previa a Internet-era difícil encontrar muchas películas… De hecho, teníamos que viajar a París si queríamos ver los filmes de Philippe Garrel o Michael Snow que no estaban editados en vídeo y que rara vez se proyectaban en Barcelona. Recuerdo perfectamente que Guerin venía a clase cargado con treinta o cuarenta cintas de VHS, y que al proyectar los fragmentos percibíamos, además, que estaba pensando también en la película que estaba haciendo y en sus proyectos. En aquellas clases empezaba a ver En construcción.