I have recently posted a CMYK ink mixing tutorial on YouTube which may be of interest to those of you who are into your inks. With many of us in lockdown, this a great opportunity to pursue fountain pen ink investigation. For best results, use fountain pen inks that are as close to the four primary colours as possible: Cyan, Magenta, Yellow and Black. And try to use inks that are pure dyes ie not containing pigment (sludge). This is not brand specific, you can mix and match brands if you wish, just as long as the inks you choose are as near to the primary colours as possible. You can find the tutorial on my YouTube channel. Search under Nick Stewart Ink Art. Have fun and please post your results here. Thanks. Nick