Yes, with a caveat. Photographic grade gelatin is a constant. The bloom (hardness) number is 250 and it's been purified of most of the extra components that can influence an emulsion -- for the better as well as for the worse. Mostly, it's just a matter of predictability, rather than good or bad. The right 'extras' were valued by the early emulsion makers, but 'food grade' covers a lot of territory. Knox brand plain has a bloom of 225, Gold leaf is ~200, and Silver leaf is ~160. Harder isn't necessarily better, but you have to take a softer emulsion into consideration through the processing chain. You may not need as much hypo solution if you find the right gelatin, so keep your eyes open for that, and take good notes. I've been adding a couple of grams of Knox to my favorite recipe, with the bulk photo grade.