Generally we do our own designs, but occasionally we're asked to print artwork from other designers. This is one such job, which we turned around in just under 24 hours.
First color, light blue:
Second color, light red:
I cut the films a bit too short, so I lost the top registration marks. Red was a bit off.
Third color, light brown:
Rather than modifying the blue layer to be a solid fill under those halftone cutouts, we decided to leave it as halftone dots and try butt registration. Gluttons for punishment.
Last color, dark brown:
Not the worst reg job on those dots:
We also used a new registration method for these posters, where we just put tabs on one edge of the paper, rather than two. We then score the stack of paper with a razor, and use the tiny cut on the edge of each page to align the paper to a similar cut on the middle tab. Worked pretty good.
Only used it a couple of times so far, but with some pretty good results.
Score the middle of your stack along the long edge with a razor. Make sure you get every sheet, but you don't need to cut very deep. Shallow cuts mean you don't even have to trim the paper afterward. Try to get your cut as perfectly vertical as possible.
Place three tabs down on your table (far left, middle, far right), and razor-cut the center of your middle tab.
The three tabs keep your paper aligned on the Y axis, so now you just slide your sheet left or right until the cuts line up.
This is important:
Don't make three vertical cuts in your stack to try getting tighter reg; if all three cuts aren't perfectly vertical, you'll find them drifting relative to your tabs as you go through your stack. A single reg cut in the center is the way to go.