Yesterday I returned to Cabin #6 in MTSF to check on the status of the pines around the cabin. The heavy wet snow had broken branches that cluttered the ground. However, I found the Cabin pine intact. The following image shows the crown of this handsome tree.
Of 4 prominent tops, one on the left, one on the right, and two in the center. The highest is the one on the left. It is between 154 and 155 feet. My last measurement yielded 154.8 feet. The center two tops are around 153, and the right top is slightly over 151.
The image shows why sine top - sine bottom is the required ENTS method. From a distance, it is not possible to tell which of these tops is farthest away. But with the sine top method, there is no problem.
Many of the pines in the Pocumtuck stand are so close that attempts to distinguish a particular pine's top and bottom from the same spot often fail. One solution is to measure the tree in segments. If you can't see the top and base of a tree to be measured from a spot, choose a prominent limb that can be seen with the top from one spot and the same limb with the bottom from another location. Measure the height increments from limb to top and limb to bottom and add the two segments. You can extend the idea of segmentation to 3 or more sections, but there is a point of diminishing returns.