OK, in order to nail down once and for all the limits of my existing process, I have created a target image to use to evaluate corrosion. The image was processed to produce several copper plates for etching.  I used my standard PosJet/Epson 2200/Puretch process. I selected the following experiments:

 

One plate was etched using the 5v/5 inch/.6 amp process (control)

One plate was etched using the 5v/1 inch/.6 amp process

One plate was etched using the 1v/5 inch/.6 amp process

One plate was etched using the 1v/1 inch/.6 amp process

 

I will vary the etching time to approximate the same bite.

 

The image has lines ranging from .001 inch to .1 inch (1 mil to 100 mil)