{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T03:28:12Z","timestamp":1780630092555,"version":"3.54.1"},"reference-count":48,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,3,16]],"date-time":"2021-03-16T00:00:00Z","timestamp":1615852800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Regional Development Fund within the Estonian National Programme for Addressing Socio-Economic Challenges through R&amp;D (RITA)","award":["L180283PKKK"],"award-info":[{"award-number":["L180283PKKK"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The application of unmanned aerial systems (UAS) in forest research includes a wide range of equipment, systems, and flight settings, creating a need for enhancing data acquisition efficiency and quality. Thus, we assessed the effects of flying altitude and lateral and longitudinal overlaps on digital aerial photogrammetry (DAP) processing and the ability of its products to provide point clouds for forestry inventory. For this, we used 18 combinations of flight settings for data acquisition, and a nationwide airborne laser scanning (ALS) dataset as reference data. Linear regression was applied for modeling DAP quality indicators and model fitting quality as the function of flight settings; equivalence tests compared DAP- and ALS-products. Most of DAP-Digital Terrain Models (DTM) showed a moderate to high agreement (R2 &gt; 0.70) when fitted to ALS-based models; nine models had a regression slope within the 1% region of equivalence. The best DAP-Canopy Height Model (CHM) was generated using ALS-DTM with an R2 = 0.42 when compared with ALS-CHM, indicating reduced similarity. Altogether, our results suggest that the optimal combination of flight settings should include a 90% lateral overlap, a 70% longitudinal overlap, and a minimum altitude of 120 m above ground level, independent of the availability of an ALS-derived DTM for height normalization. We also provided insights into the effects of flight settings on DAP outputs for future applications in similar forest stands, emphasizing the benefits of overlaps for comprehensive scene reconstruction and altitude for canopy surface detection.<\/jats:p>","DOI":"10.3390\/rs13061121","type":"journal-article","created":{"date-parts":[[2021,3,16]],"date-time":"2021-03-16T21:42:41Z","timestamp":1615930961000},"page":"1121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["An Evaluation of the Effects of UAS Flight Parameters on Digital Aerial Photogrammetry Processing and Dense-Cloud Production Quality in a Scots Pine Forest"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0758-0656","authenticated-orcid":false,"given":"Raul Sampaio","family":"de Lima","sequence":"first","affiliation":[{"name":"Institute of Agriculture and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mait","family":"Lang","sequence":"additional","affiliation":[{"name":"Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"},{"name":"Tartu Observatory, University of Tartu, Observatooriumi 1, EE-61602 T\u00f5ravere, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0416-1608","authenticated-orcid":false,"given":"Niall G.","family":"Burnside","sequence":"additional","affiliation":[{"name":"Centre for Aquatic Environments, School of the Environment and Technology, University of Brighton, Cockcroft Building, Moulsecoomb, Brighton BN2 4GJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miguel Villoslada","family":"Peci\u00f1a","sequence":"additional","affiliation":[{"name":"Institute of Agriculture and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tauri","family":"Arum\u00e4e","sequence":"additional","affiliation":[{"name":"Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"},{"name":"State Forest Management Centre, Sagadi Village, EE-45403 Haljala, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diana","family":"Laarmann","sequence":"additional","affiliation":[{"name":"Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7391-5530","authenticated-orcid":false,"given":"Raymond D.","family":"Ward","sequence":"additional","affiliation":[{"name":"Institute of Agriculture and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"},{"name":"Centre for Aquatic Environments, School of the Environment and Technology, University of Brighton, Cockcroft Building, Moulsecoomb, Brighton BN2 4GJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ants","family":"Vain","sequence":"additional","affiliation":[{"name":"Institute of Agriculture and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kalev","family":"Sepp","sequence":"additional","affiliation":[{"name":"Institute of Agriculture and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 5, EE-51006 Tartu, Estonia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.future.2014.10.029","article-title":"Remote Sensing Big Data Computing: Challenges and Opportunities","volume":"51","author":"Ma","year":"2015","journal-title":"Futur. 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