I ended up dry incubating my duck eggs after day 10 when I realised they weren't losing moisture fast enough. I ignored all the standard stuff about duck eggs needing more humidity than chicken eggs and just went with my trusty set of digital scales, Brinsea's recommendation of a 15% weight loss, and some common sense. Come lockdown I bumped my humidity from 30% to 75-80% and sat back to wait... The first one pipped yesterday morning, and did nothing more for well over a day. Having read about ducklings on this forum, I knew they normally take much longer than chickens to hatch, so I refused to get concerned. I went off out to work this morning, and came back home this evening to a huge beefy duckling just about filling my little incubator. Wow! I also have one more pipped, and another egg rocking and rolling in there. Conclusion: If you're not sure what humidity to go with, weigh your eggs and you can get it right first time.