In figures 1 and 2 we see a design created digitally (in this case) that has been transferred to a screen and squeegeed out onto photo paper, then finished as a chemigram. In fig. 1 we started with fixer, in fig. 2 with developer. Notice how, from a common starting point, the images evolved differently in the 30 minutes to completion, due to accidents, imperfections, and random effects along the way - interesting. You'll want details: screen mesh was 160, Golden MSA was undiluted, the paper was Bergger. Other choices of mesh, resist, dilution and paper will lead to other results even with the same initial silkscreen design. Clearly, if you opt for a more viscous resist you may want a larger mesh, otherwise your resist won't get through; I've used a mesh of 60 for honey, which is almost a hardware-store mesh level for screen doors.
Another reason to use a silkscreen approach to chemigrams is to allow you to work with photographs. Sure, you can always do a chemigram and over- or underlay a photo, but if you really want to mackie-ize it you've got to run it through a screen. Here there are several options mostly involving photoshop and in the future we want to devote a post just to this. To whet your appetite, we leave you with a detail of a Cordier photo chemigram, from that distant period before photoshop:
|Cordier, Hommage à Nonyme 1972, 1976, detail|