dust? › Forums › Spectroscopy › Anomolous absorption line? › dust? 25 February 2021 at 7:06 pm #583892 Kevin GurneyParticipant Hi Robin Thanks for tip… I’ll have a look later. Its clear outside so running another session. Repeating the gam cas HeI… I’ll let you know if it spontaneously dispapears – or persists [BTW I am using a 460EX too]
