# Logarithmic profile

> [HTML Version](logarithmic_profile.html)

For the logarithmic profile the length of the unmodified cylinder and the amount of crowning has to be defined.

The profile is calculated as:

(./images/all_img247.png)

Using Pr = 0.0005\*Dw and Lwu = Lwe – 2.5\*Dw leads to the default profile according [ISO 16281](bibliography.md#iso_16281) for long rollers.