Yes, with the frames I look last night: for some, a two point calibration with zero and hydrogen beta seemed to work very nicely, with the alpha, beta, gamma and delta Balmer lines superimposing precisely on target in RSpec. In other frames this wasn’t the case. I guess it is just an effect of seeing? I am looking forward to seeing the spectra of SN2018gj that will appear over the next few days. I note you are discussing the uncertainty around the SNII subtype on the ARAS forum. David
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