Rounding/truncating error with QNH?
#1
Hi!

I was tracing an error in the ATC software I use (PF3) about ATIS reporting QNH 2 lower than in shown in FSXWX's METAR.
The problem in PF3 has been found and fixed in the current beta (converting QNH from "mb" to "in Hg", truncating after two decimals, converting back to "mb", truncating again).
Now it is only 1 lower than shown in FSXWX's METAR.

Using FSInterrogate2 I noticed that offset CC28 (New Weather Interface QNH) shows e.g. 1006 if the METAR shows 1007 for some airport (I tried it at various airports in Germany and the Netherlands), but 0EC6 (QNG near the aircraft) shows a value with higher precision, e.g. something like 1006.xyz (I don't have the exact value right now).

Could it be that FSXWX converts QNH1007 to 29.73 in Hg (instead of 29.73669) and that value back to 1006.7734, which gets inserted into FSX, which in turn truncates it to 1006?
I have tried inserting values with decimal places into the NWI, but offset CC28 always shows numbers without decimal places.
Can you round the QNH value before multiplying it with 16 to insert into FSX's weather? I hope/suspect this way the offset will be correct.

I'm currently using FSXWX 1.5.5 with FSX (boxed+Acceleration).

P.S.: Thank you very much for FSXWX! I started using it few months ago (after setting the weather manually for a long time) and now can't imagine flying without it.
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