The academy awards site list more than 40 minutes as a minimum in order to be of feature length under submissions.
Is there any consensus on length. My feeling is most are too long. But what is a general rule? Any feedback would be helpful.

It's a bit like how long is a rope, isn't it? I guess it varies depending on your subject and the style you choose. My feeling is you get in, tell your story and get out.

My favorite documentarian, Frederick Wiseman, has films ranging from 80 minutes to nearly four hours. And then there's Ken Burns. And if you stretch the definition, way at the other end of the spectrum there's Michael Moore. All depends upon the subject matter, I suppose.

Also I think you should keep in mind your intended distribution medium. DVD? Theatres? TV? All will have different preferred lengths/requirements. Do you have a distribution deal in place? What does your distributor say?

My feeling is most are too long. But what is a general rule? Any feedback would be helpful.

Don't worry about the "general rule", worry only about your film. What Ken Burns or Albert Maysles or does is not that important if they're not working on your film.

Does your film feel too long? Does it tell the story?

Mine have gotten progressively shorter over the years. My standard is 28:30 because:

That's about as long as anybody will spend watching it online (assuming it's watchable).

That's the length that will play in the half hour time slots of public access stations.

That's all it takes to tell the story.

Here are a couple of samples:

ARTfeast of Santa Fe (ARTsmart) Documentary, Full Length - YouTube (http://www.youtube.com/watch?v=S6hiTR24wbA)

Stories of the Spill - Documentary, Full Length - YouTube (http://www.youtube.com/watch?v=nV777pph6fw)

Regards,

t.