After reading a few APUG posts on the subject of cyanotypes, I set a couple of sheets of paper into a tray of water with a bit of diluted vinegar. After drying, coating and making the exposure I used a first clearing bath with a small amount of citric acid added. Now I immediately noticed a huge amount of blue being washed off!...something I never saw before using the vinegar and citric acid. And yet the resulting prints were, in my opinion, much better! It's my understanding that both the vinegar treated paper and the citric in the first bath are for the purpose of retaining mid tones...and it seems to have done that. Today, I made a print with only the vinegar treated paper and without the citric bath. Also a very improved result...but without any blue being dramatically washed away. So now I'm wondering if it is the citric bath that caused so much blue going down the drain, or is it the combination of vinegar treated paper and a citric bath? Anyone have any thoughts about vinegar treated paper vs citric acid bath?