# How to find good optical flow parameters?

Asynchronous topologies are not very convenient to look for the best parameters
for a computation. It is better to use the optical flow work directly as in
this example:

```{literalinclude} optflow_try_params.py
```

The parameters in `params.series` are used to define an object 
{class}`fluiddyn.util.serieofarrays.SeriesOfArrays`
and to select one serie (which represents here a couple of images). It is also
what is done internally in the topology. Have a look at
[our tutorial](https://fluiddyn.readthedocs.io/en/latest/ipynb/tuto_serieofarrays.html)
to discover how to use this powerful tool!