Smoothed fixed altitude field is shifted to the right

[William_Jones]

Since last Friday, the fixed altitude field has been smoothed (which I think is a good change). However, compared to the original altitude, the profile is shifted to the right, i.e. the peaks on a route appear later on the graph than they were reached in reality (see example below). They are also misaligned with the map.

This may be because the moving average window is looking at earlier points when computing the average, rather than being centered. Note that this doesn’t occur when applying a moving average to a custom chart (including altitude), so might be specific to the new fixed altitude smoothing

[david]

We have switched to using an exponentially weighted moving average to create the fixed altitude stream. Each new point only contributes 5% to the current altitude. In our testing, this produces a much less noisy altitude trace and better total ascent and descent data than using the map altitude data as-is.

However it will lag which is what you are seeing.

We are also busy integrating slightly more accurate maps, which is why there hasn’t been an announcement about this change yet.