{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:28:23Z","timestamp":1772252903072,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,11]],"date-time":"2018-01-11T00:00:00Z","timestamp":1515628800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Dynamic laser speckle (DLS) is used as a reliable sensor of activity for all types of materials. Traditional applications are based on high-rate captures (usually greater than 10 frames-per-second, fps). Even for drying processes in conservation treatments, where there is a high level of activity in the first moments after the application and slower activity after some minutes or hours, the process is based on the acquisition of images at a time rate that is the same in moments of high and low activity. In this work, we present an alternative approach to track the drying process of protective layers and other painting conservation processes that take a long time to reduce their levels of activity. We illuminate, using three different wavelength lasers, a temporary protector (cyclododecane) and a varnish, and monitor them using a low fps rate during long-term drying. The results are compared to the traditional method. This work also presents a monitoring method that uses portable equipment. The results present the feasibility of using the portable device and show the improved sensitivity of the dynamic laser speckle when sensing the long-term process for drying cyclododecane and varnish in conservation.<\/jats:p>","DOI":"10.3390\/s18010190","type":"journal-article","created":{"date-parts":[[2018,1,11]],"date-time":"2018-01-11T13:36:15Z","timestamp":1515677775000},"page":"190","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["A Portable Dynamic Laser Speckle System for Sensing Long-Term Changes Caused by Treatments in Painting Conservation"],"prefix":"10.3390","volume":"18","author":[{"given":"Alberto","family":"P\u00e9rez","sequence":"first","affiliation":[{"name":"Dep. d\u2019Inform\u00e0tica de Sistemes i Computadors (DISCA), Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5898-6277","authenticated-orcid":false,"given":"Rolando","family":"Gonz\u00e1lez-Pe\u00f1a","sequence":"additional","affiliation":[{"name":"Dep. Fisiolog\u00eda. Unidad de Biof\u00edsica y F\u00edsica M\u00e9dica. Facultad de Medicina y Odontolog\u00eda, Universitat de Val\u00e8ncia, 46010 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4203-4316","authenticated-orcid":false,"given":"Roberto","family":"Braga Jr.","sequence":"additional","affiliation":[{"name":"Dep. Engenharia (DEG), Universidade Federal de Lavras (UFLA), 3037 Lavras, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5782-4284","authenticated-orcid":false,"given":"\u00c1ngel","family":"Perles","sequence":"additional","affiliation":[{"name":"Dep. d\u2019Inform\u00e0tica de Sistemes i Computadors (DISCA), Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"},{"name":"ITACA Institute, Camino de Vera, s\/n, 46022 Valencia, Spain"}]},{"given":"Eva","family":"P\u00e9rez\u2013Mar\u00edn","sequence":"additional","affiliation":[{"name":"Dep. de Conservaci\u00f3n y Restauraci\u00f3n de Bienes Culturales, Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7062-245X","authenticated-orcid":false,"given":"Fernando","family":"Garc\u00eda-Diego","sequence":"additional","affiliation":[{"name":"Dep. de F\u00edsica Aplicada, Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Schnars, U., Falldorf, C., Watson, J., and J\u00fcptner, W. 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