› Forums › Spectroscopy › What wavelength error is acceptable with an Alpy? › Residuals
31 October 2018 at 12:03 pm
#580150
![](https://britastro.org/wp-content/uploads/2019/12/picture-5132-1575710618-80x80.png)
Participant
Hi Robin the 3rd order fit has 0.57 and the fourth 0.34. The fourth is as the ISIS fit. Though looking at this again I don’t think this is an issue.
DAVID makes an interesting point about the line wavelengths though.
Regards Andrew
I will need to do this again as I used Robin’s figures!