If you peer past the green stuff in the foreground, is that the type of tent you're talikng about? These NZ tents come in two sizes and the centre pole length is supposed to be three-quarters of the diameter of the tent. Your tent may be a different pattern, so possibly check it by laying the tent out on the ground sideways (like a big triangle of canvas) and measure it.
PS keep the flamethrowers away from the tent as old canvas preservatives can make it quite flammable
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