I am using Diamine Majestic blue in cartridge from in a Kaweco Elite M nib and bottled ink in convertor in a Diplomat Aero M nib. The thing is this: the Diplomat is consistently writing several shades darker than the Elite. I've tried letting the ink dry in the Elite feed to concentrate with minimal impact. I did a swab with the ink and the colour seems to be a lighter "diluted" shade of the same rich dark colour. Any suggestions for what this could be? Is it dampness in the feed from when I cleaned (and dried) the Elite? Its frustrating because the ink is not doing "exactly what it says on the tin"... Any help appreciated tbzbbt