We are, however, relying on the linearity of the lens and most will introduce a varying degree of distortion to the image, particularly when zoom cameras are used in their wide-angle setting. Though this sounds a little Heath-Robinson, this method should be able to produce fairly reasonable (if not scientific) results. Paste the image of the measure as many times as necessary all the way up the tree (see picture on left) and then you can calculate the height. Also, remember to include the top of the tree - it's easy to miss this when setting up the camera.Īt your computer, use the selection tool in a photo manipulation package (unfortunately Paint will not do) to select and copy a small rectangle including the exact length of the measure. Any closer and "perspective" error will become significant - do a scale drawing as an example and you will see what we mean. The camera needs to be placed a long way back from the tree for the most accurate measurement ideally at least twice the height of the tree. (3 metres would be better but the tape may buckle and fall). Standing to one side, hold a steel tape measure extended up 2 metres ensuring that the bottom of the measure is level with the bottom of the tree. Set the camera to timer mode and run back to the tree. You will need to place the camera a good distance away from the tree on a tripod or some other suitable object. Where the ground slopes the usual practise is to use the side of the tree with the highest ground level.Ī camera is needed to attempt this method of measuring the height of a tree. You might have to scrape away some of the detritus to get to the actual ground level. To measure the girth it is usual to position the tape measure at 1.5 metres from the ground (around chest height, but refer to chart on the left). Remember that it is important to make a note of the date that you measure, and feel free to contact us if you would like us to include a record of your findings and/or measurements of Redwood Trees, (preferably with photographs). Here are some tips on how to measure the Girth and Height of trees. Giant Redwood / Giant Sequoia / Wellingtonia pmd models, you must have the later versions (XP and up).This site refers to the three types of Redwood by the names commonly used in the U.K: Video card acceralates Direct3D and OpenGL.
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