ISIS merged order wavelength shift error
Posted: Mon Jul 04, 2022 1:31 am
Some time back I discovered that when ISIS generates a merged profile from eShel orders that there is a significant wavelength error.
I did report this at the time, in May, (see http://www.spectro-aras.com/forum/viewt ... f=8&t=2959) but there were no useful responses. As I consider this a significant problem I am now trying again.
I am using the latest 6.1.1 version of ISIS. I don't know if earlier versions had the same problem but if they did then I certainly never noticed it.
There is no wavelength shift with the individual orders, so the error is only introduced during the merge process.
The plots below show the correct wavelength for individual orders and the shift for the merged orders.
Has anyone else had this problem?
Cheers,
Bernard H.
I did report this at the time, in May, (see http://www.spectro-aras.com/forum/viewt ... f=8&t=2959) but there were no useful responses. As I consider this a significant problem I am now trying again.
I am using the latest 6.1.1 version of ISIS. I don't know if earlier versions had the same problem but if they did then I certainly never noticed it.
There is no wavelength shift with the individual orders, so the error is only introduced during the merge process.
The plots below show the correct wavelength for individual orders and the shift for the merged orders.
Has anyone else had this problem?
Cheers,
Bernard H.