suunto pm5 clinometer..........

[chris hennelly]

Please anyone with one of these nifty bits of gear......give a simple explanation of hoe to use it.........................................

[Perkins]

There is a knurled focussing knob at one end with a slit in it. Look through the slit and you can see the numbered dial. If you hold it horizontally it will read zero. As you tilt upwards and downwards, the dial rotates.

 

Is there a percentage scale on that model?

 

To get a height reading for your tree, you first need to know your distance from the tree, so wheel out from the bottom of the tree about 20m or 30m. A nice round figure anyway. We'll use 30m in the example below...

 

Look through the slot with one eye and look at the tree with the other eye. Line up the horizontal line inside the suunto with the top of the tree. Take the reading off the scale.

 

The tree height is the wheeled distance multiplied by the percentage. so 70% would be 21m (i.e. 30 x 0.7 = 21m).

 

Geddit?

 

This is a simple explanation, there are adjustment figures for if you are sighting up hill or down hill. There is a user manual available.

[chris hennelly]

Perkins...many thanks for the explanation.......much easier than the manual,which defied even the brains of my 9 yr old daughter!

Have always previously used eye/stick method which has been quite accurate ......but the suunto will be even accurater and provide a bit of magic for the client,(i can always source a stick off ebay for back-up).Thks!

[Perkins]

It works by exactly the same method as the stick method i.e. similar triangles. 45degrees is 100% on the scale i.e. you are standing at the point that the tip would land if you felled the tree.

 

The bonus is that you can measure a tall tree in a small space, with greater accuracy.

 

Good luck and happy clinometeringering

[N1ck]

There is a version that I have that is even simpler. If you look through the eyepiece and point it at the ground the wheel has 2 scales one labelled 10m and one labelled 15m. You literally stand with your back to the tree, walk out either 10m or 15m, turn round, sight the top of the tree using the appropriate scale (keep both eyes open) and read off the height. All you need to do is to remember to add the height from horizontal (eye height) to the ground - usually 1.5m on level ground or take it away if the ground slopes upwards between you and the tree.

[DrewB]

The TruPulse 360R is even easier-point it base of tree, click, point at top of tree, click, and voila it tells you the height and the lean of the tree.