Printing technique

I was examining several of my proofs up close today, and noticed that the grain of the tone was quite different in many of the proofs.  In some proofs, the grain was coarse looking, while I found a few others that lacked the grain and looked significantly more refined.  There proofs had an almost velvet-like texture. Even the color of the ink seemed slightly different; the coarser proofs looked more grey while the smoother proofs had a warmer, brownish tone. (the ink I print with is Renaissance black, a black ink that has a lot of burnt umber mixed into it)

I concluded that I’ve been over wiping many of my proofs, which is what creates that coarser texture. I hadn’t paid a lot of attention to it earlier, but upon closer inspection I could see that the difference is really quite dramatic.  I had been frustrated by the coarser proofs because they lacked the subtlety in tone that I’m looking to achieve.  It’s nice to know that it is simply a technical printing issue, and not because I am doing a bad job of the scraping the plate. Now I know that I have to stop wiping the plate much earlier to achieve that smooth velvety surface that I want.