TonyB wrote:
> On my chart Imray G11 I have a compass rose which shows in writing
> "Variation 2º 45' E (2005) Increasing about 5' annually."
>
> Fine. But the compass rose points to 5º on the true north ring rather
than
> 2.45 - why is this?
Here are some possible reasons.
1) The orientation of the rose is wrong.
2) The writing is wrong.
3) They're both wrong.
4) Their compass rose printing technology doesn't handle arbitrary
rotation, only whole multiples of 5º.
5) They expect the chart to have a life of 50 years or so, and
printed the rose as showing the mean direction for the period.
6) They issued a new edition of the chart in 2032, but without
updating the writing on the rose, since there was no need, as it
was still correct. This is your grandson's chart who paid you
a flying visit from the future, and brought it back to show you,
then forgot to take it with him when he went back.
I wouldn't bother with this Mickey Mouse stuff. I've yet to see an
Imray chart which can hold a candle to Admiralty ones.
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