A trick for CDendro users:
Sometimes I want to continue measuring from a new point, like this:
Here, this is done when going from point 58:1 to 58:2 on the same ring. Then I register point 58:1 and 58:2 as a group.
So before clicking on point 58:1, I click on the datagroup button
to change the mode from a-single-point-per-row.
You can also use the right mouse button to change this mode!.
Then I click on point 58:1 and 58:2.
The group mode will switch back automatically to single point mode when
data is known to be dendro data!
The written data will look like this:
26.872,13.607
24.316,14.512
21.538,15.464
18.655,16.210 15.226,7.940
12.353,9.273
9.083,10.575
6.371,11.972
4.101,13.401
I.e. with the two points 58:1 and 58:2 on the same line.
CDendro is set up to handle this type of grouped data.
This is a very useful method when you have to make a jump in your measurements when ring widths are laying aslant on the picture.
Of course, if tree rings are not very concentrical you have to be careful when interpreting your data if you have moved your radii of measument within the stem!
When measuring across a crack you can also use the method described above.
Though when setting the point 25:1 above you have to compensate for the width of the crack to make the distance between point 24 and 25:1 correspond to the actual width of the broken ring.
Using the CrackMarker tool when measuring over a crack
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There is now a new tool in CooRecorder to measure over a crack - the CrackMarker tool. (Development version of CooRecorder, Febr 19 2009.)
The picture above shows two possible paths for measuring across the crack. The upper path is very precise and it is the method to be prefered when possible, i.e. the old way as described above with a pair of measuring points. Though there are cases when you cannot traverse the crack that easy. Then the lower path may be considered! When using the new CrackMarker tool you can set a crackmark point at each side of the crack as shown above. When CDendro reads the .pos file, it will subtract the width of the crack from the full width of the ring. The main problem with this method is that it is difficult to see the edges of the crack as the scanner does not look in right angles towards the wood surface. Instead this picture was obviously taken aslant, as it shows a bit of the inside of that crack as a light area. To use the CrackMarker tool, click on its button and it will light up. You can also select it with the M key on your keyboard. Then click where you want to set the points. When ready, click e.g. the D key (data mode) to continue measuring as normal. |
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You may set a single crackmark in front of a ring border as shown above.
You may do so also in front of a W-point at a latewood/earlywood border.
There is no limit for the number of crackmarks within the same ring but they have to be on a straight line to make the measurements correct.
Note: Old versions of CDendro will ignore these crackmarker points. |
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Note: There has been a report on CDendro ignoring %gap %gap markers when having set Windows to
1. running with decimal separator set to a comma (,) and 2. with Polish selected as the region. The error can be circumvented by changing the decimal separator in Windows to a dot (.), though this might have side effects on other software and old data. The error has been fixed in the TEST version of CDendro 7.5 from 2 November 2011. |