```--- a/tutorials/tca/en.2006-03-14.shtml
+++ b/tutorials/tca/en.2006-03-14.shtml
@@ -115,6 +115,7 @@

<p>
If you don't have access to octave, here is how the parameters are calcuated (red channel):
+</p>
<pre>

scale = hfov_green / hfov_red
@@ -125,6 +126,7 @@
c = c_pt * scale^2
d = d_pt * scale
</pre>
+<p>
Use a similar calculation for the blue channel. The values of a_pt, b_pt, c_pt are the distortion parameters from Hugin.
</p>

@@ -136,11 +138,9 @@
<p>
open octave and type:
</p>
-<p>
<pre>
octave:2&gt; display_tca('pano_tutorial.pto');
</pre>
-</p>
<p>
This will produce two figures:
</p>
@@ -176,6 +176,7 @@

<p>
The calculated correction parameters are printed to the console:
+</p>
<pre>
correction parameters read from pto file:
-r 0.0000000:-0.0019056:0.0030218:0.9995177
@@ -184,6 +185,7 @@
-r 0.0001368:0.0002725:-0.0006605:1.0007630
-b 0.0011642:-0.0046154:0.0055706:0.9989218
</pre>
+<p>
Choose the set of parameters that looks better on the diagram above. I suspect that the second parameter set
is usually preferable.
</p>
@@ -201,12 +203,14 @@

<p>
Correct TCA using fulla:
+</p>
<pre>
fulla  -r 0.0001368:0.0002725:-0.0006605:1.0007630 \
-b 0.0011642:-0.0046154:0.0055706:0.9989218 \
input.tif output.tif
</pre>

+<p>
This correction can be combined with all other correction options of fulla,
like the distortion correction based on the PTLens database (-p option) or the
vignetting correction.
```