This sounds to me like fog, whether is chemical or from light is difficult to tell with your explanation. So, does the entire negative looks like it is gray and even? if so, then it probably is cehmical fog from the developer, and/or outdated heated film. If it is from the developer i would think is overdevelopment with too strong a developer. If you see streaks then it probably is a light leak.(posted 8249 days ago)I hope this helped, if you can be a little more precise about the appereance of your film we can probably help you more.