with my current exploration of different films, lighting conditions etc. it has been very useful to me the fact that you can re-wind a film mid rolll and leave a trailer to be pulled out and reloaded as you would any new film. just wondering however how best to go about getting back to your previous place in the film once you reload it. I have just been going in subdued light (as they say) and covering viewfinder and taking picture with the lens cap. is this enough? what are your thoughts and ideas on how to go about this useful process.