When I modify the viewing Angle, I get a warning that there are too many iterations

[Dirac666666]

Dear author,

hello, I used function isStopCondition in my metric.c, and then I set the observation Angle from 70 degrees to 5 degrees, but I found that the warning :"SEVERE: Photon::hit: too many iterations (100001 vs. 100000), break." appears when the observation Angle is 5 degrees, and there is no such warning at 70 degrees

Do you have any good suggestions?

I am looking forward to receiving your response.

[Dirac666666]

In addition, I changed the observation Angle to a smaller Angle, which I set to about 0 degrees, and I found that the photon ring on the picture I obtained of the accretion disk had black spots. I checked these black spots and found that the value of these spots is 0. I would like to ask you if this phenomenon is normal.

My guess: The effect of the observation Angle
Small Angle approximation: When the observation Angle is very small (e.g. 0.01), it can cause some instability in numerical calculations. A small Angle can mean that the light is almost parallel to the polar axis of the black hole, which can lead to difficulty in converging numerical algorithms when calculating light trajectories or other related physical quantities.

There are my specific documents and picture details in this attachment
problem.zip