[ptx] suggestion for "Hugin Overview" tutorial.

[Marco Molteni]

Hi,

I have a suggestion for the Hugin Overview tutorial, to add at the
end of "picture taking tips".

Here is the text:

Another trick to keep the tonality even is to specify the white balance,
instead of leaving it to auto. Either calculate the white balance using
a white or neutral grey surface, or just choose one of preselected white
balance settings: sun, shade, etc. The reason is that auto white balance
can change between views, giving for example a blue cast on one picture
and a yellow cast on another.

marco
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