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Subject: Re: [Homebrew_PCBs] Re: How fine can you etch with toner transfer?

From: DJ Delorie <dj@...>
Date: 2008-10-23

"martin_schoenegg" <Martin.Schoenegg@...> writes:
> No this only means, hat you can adress this resolution. May be the
> stepsize comes in this region, but there is nothing said about the
> size of one pixel. Especialy inkjets are designed to produce

Well, yeah. Relatively speaking though, I can compare 0.833 mil to
0.174 mil and say "it's much more accurate". What I really mean is
that the line sizes - as drawn - will be much more consistent, because
a variation of one pixel is a much smaller percentage of the line
size.

This means that, if I know my process can handle 6 mil lines, I won't
have to worry about the 5 mil lines, or the spaces between 6.666 mil
lines - because the films will more accurately reflect my desired
sizes, compared to a laser printer.

My inkjet is good to about 0.5 mil as far as drop placement accuracy
goes. However, I know that "fuzzy edge" will be in the same spot
every time. So, if I know I can do 6/6 rules with a 0.5mil fuzzy
edge, at least the results will be consistent - a one pixel difference
is negligible. One pixel on a laser printer is BIG compared to what
I'm trying to achieve.

On a laser printer, for 6/6 rules (er, 6.66 rules), off by one pixel
means the line is 25% smaller. On an inkjet, off by one pixel would
only be 5% smaller.