the image quality in print stays the same if it's rendered in 300 or 15230 dpi (if you scan images with 300 dpi or anything else, it is quite different), if you are doing normal, offset printing. so: - ask for the page size (in inch), let's say 10 x 10 inches (plus bleed if image goes from border to border - usually 3-5 millimeters) - render in poser an image 3000 x 3000 pixels at 72 dpi - load in photoshop (or such) and resample to 300 dpi - ask if magazine needs cmyk or rgb image all this change if magazine is printed with finer raster, then you'll need for instance 400 dpi or finer, but it's best to ask before you start.