# Dealing with NaN pixels

When there are NaN **pixels** in your render you can either use the value of an adjacent pixel or the average of all adjacent **pixels** to fix it. The latter will probably give better results, but won’t work when there’s another NaN pixel next to the first one. In an expression node, type:

1 |
isnan(r)? r(x+1,y):r |

or

1 |
isnan(r)? ((r(x+1,y)+r(x+1,y+1)+r(x+1,y-1)+r(x,y+1)+r(x,y-1)+r(x-1,y+1)+r(x-1,y)+r(x-1,y-1))/8):r |

Mirroring animation timing using tcl Dealing with Inf or -Inf pixels