We are all familiar with the notion that there are 'Rules' to photography, but I am sure that most of us only know some of them. Also, possibly, we may not fully understand those that we do know. There is the famous 'rule of thirds' but should the subject of the shot fall centrally on the line dividing the image into three, or should it be centred on the area that is one third of the frame wide (or high). Perhaps this post could be used by us all to build a library of these rules, with a short explaination of what they mean (if needed). Besides being helpful to potential mewcomers to the hobby, it will serve to remind us of the ones we have forgotten. Some may only apply to film, others to digital, many to both. I will kick of with this one: Rule 1. The sunny 16 rule: When shooting front lit subjects on sunny days, set the aperture to f/16 and your shutter speed to the nearest corresponding number to your film's ISO rating Does it work and what is your favourite 'rule'?