On 2011-10-27, wrote:
http://www.flickr.com/photos/2768312...in/photostream

Previously when I saw pits like these I thought it was caused by pin
holes in the resist. There was some discussion about its here. I
firmly believed that it was the hydrogen bubbles cavitating causing
this. However, in this case there is *no* resist!

Are those truly pits, or are they projections? I could imagine
air bubbles (or hydrogen) forming on the surface which would prevent as
much access from the etchant.

Either tapping the edge every so often, or applying ultrasonics
from a cleaner might break them up fairly quickly.

Good Luck,
DoN.

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