I am not on the current release. But in past releases, if you enter a number of analysis rays greater than the number in the file, the entry will default to the total number of rays in the file. Below the file contains 1E6 rays, but I entered 1E15 as a number well over any reasonable value. If you want to trace fewer rays, it is important to set Randomize? to 1, since many ray files contain rays in some systematic order.

Thanks David.

That’s what I thought as the only way to know, keep increasing the analysis rays till it’s maxed out.

Yes, I always have to check the randomize column to make sure it’s set to 1.

You don’t have to keep increasing the analysis rays. Just try to enter an impossibly high number and the entered value will default to the total number of rays in the file.

The Help File for the Binary Source File Format can help to provide a lower bound as well

Take care,

David

Yes, I meant increasing by factor of 10, not little by little.

Good to know max possible in Zemax is 4B rays.

Another good indicator seems to be the lumen in file is smaller than total value when analysis rays is smaller number than the max number in file.