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I am planning to make a PCB and putting solder mask on it but I don't have my own laser printer to print the transparency for the mask. I do, however, live near a printing shop with a laser printer who can print glossy/photo paper but not transparencies. So I am thinking if I can use spray paint or a marker to "draw" on empty transparencies by using a soldering paste stencil as a guide. I have seen this question being answered but its not what I'm looking for. So will spray paint or a marker block UV for solder mask/resist so that the pads won't dry?