Bar chart opacity changes with longer time range

I noticed that plotting different time scales causes the opacity of my overlaid bar chart to fade. How do I correct this? In the first image, I plotted over a range of 2 years and in the second I plotted a 1 year time range. Notice that the former has a significantly faded bar chart, I would expect that these two charts to be the same regardless of range.

Sidenote: I am β€œhacking” the chart to center on the primary axis, if anyone can help me figure out how to directly set the y-axis range of the secondary axis that would be very helpful as well.

import plotly.graph_objects as go
from plotly.subplots import make_subplots

filtered = df[(df['date'] > '2017-1-24') & (df['date'] <= '2018-1-24')]

fig = make_subplots(specs=[[{"secondary_y": True}]])

fig.add_trace(
    go.Bar(
        x=filtered['date'], 
        y=filtered['divergence'],
        opacity=0.5
    )
)

fig.add_trace(
    go.Scatter(
        x=filtered['date'], 
        y=filtered['price'],
        mode="lines"
    ),
    secondary_y=True
)

fig.update_layout(yaxis_range=[-9, 9])
fig.show()