The expression "HOW LONG IS A PIECE OF STRING" is generally used as a response when you can't sum up how long it will take to do something. Say Rob, how long will it take you to get around to finish watching the IRISHMAN? "how long is a piece of string" ( I know I am a trash person for not watching it yet)
One thing that does have a more definitive answer is how long is your short film? If your response to this is "HOW LONG IS A PIECE OF STRING" then I am both worried and fully prepared to be in for a long night at the movies.
A while back I was chatting with a student after class and he was looking for help. He was about to take his first steps in the film-making process and was preparing his first short film. I asked him what the running time would be and he told me about 50 minutes. I paused, I wasn't sure the best way to say it but i felt, THAT'S WAY TOO LONG. I advised that he would be better off adding an extra 25/30 minutes and going for a feature. Naturally I can only comment on running time from the perspective of the Dublin Smartphone Film Festival and other festivals of our size but a good rule of thumb when making a short film is shorter is better.
Yes Rob but it's my vision and it needs to be 45 minutes long
Listen, I for one am not going to tell any filmmaker to compromise their vision in order to get their films screened at a festival. You need to remain true to your story and if it takes 45 minutes then so be it. As defined by the academy of motion pictures, a short film is anything less then 40 minutes. But their is a logic to keeping a film short (more on this) and the more screen time you add to a short the less chance it has of being screened.
The way a script breaks down is that it is normally one page of screenplay for approx one minute of screen time. It normally doesn't matter whether the script is full of action or dialogue or a mix of the two. Its just a good rule to follow if you are an aspiring screenwriter. There are of course exceptions to the rule. The script of the Lord of the Rings was 118 pages but the movies are 3 hours long.
So in a practical sense what you put on the page should reflect the length of your film. If you find yourself on page 40 of your short film screenplay it is maybe a sign that you need to trim it down a little. Take it from me. The first film I ever made was a wordless time travel drama. By the time I was finished the film clocked in at 22 minutes in length. I was adamant it couldn't be touched. I sent it to a few festivals but it got no traction so eventually I gave up. Recently I found a copy of it and I decided to re-edit it. This time, through my older more world weary eyes, I was able to gut it down to 3.5 minutes long and honestly, I could have made it shorter. The point of that story is to really evaluate what you have done, seek the council of people and take their points on board. My film was filled with great B-roll footage to reinforce the central characters emotional journey but a lot of it was unnecessary and didn't speak to the audience the same way I thought it did.
SHORTER IS BETTER
Making a short film can often times be a challenge and it is a different approach to making a feature. You need to be economical with your storytelling with a focus on one subject through to the end. We are so used to watching feature films that sometimes this bleeds into how we write shorts. We include things that might play better in a story that has more time to breath. The average recommended time for a short is less then 10 minutes so 9-10 pages of script (roughly). This I would argue is changing with peoples attention spans and peoples more developed visual approach to storytelling. For me personally I have noticed that the 7 minute mark is the sweet spot. To be honest, a solid one to two minutes will do wonders for you because they are short and easy to program.
SHORTER IS CHEAPER
The longer your film the more it will cost. A lot of times you are putting together your films with little or no budget. So the longer your film goes the more money it will need, be it renting locations, paying actors or even catering. Having a 40 page story on paper maybe incredibly expensive once you go to put it on screen.
SHORTER IS PRACTICAL
As I mentioned above, the longer your running time, the less chance it will have of being screened. The longer your film gets the more your running time starts to work against you. Festivals are inundated with films to be screened and the desire is to screen as many films from submitted filmmakers as possible. Longer shorts become an issue when it comes to programming an event because in order to show your 15 minute film it means not showing three or four shorter films from other filmmakers. Your film could be excellent but that 15 minute running time might start to work against you if you have four other excellent films that can be shown in its place. You find that the longer form shorts we show generally tend to be a masterclass and need to be shown. This isn't a new thing strictly for festivals. It has happened with main stream movies and cinema for years. The normal Hollywood film aims for 120 minute mark. It is even built into contracts stating that the filmmakers will deliver a film no longer the 2 hours and 8 minutes or 128 pages. Why? Practical reasons. It has an advantage in theaters because they can have more screenings to make more money. How long this will last with the move to streaming and the audience demand for long form bingeable content? We could be looking at every movie with IRISHMAN running times soon.
Its important to understand there a number of factors at play when submitting your film to a festival. Running time can work against you so its important to keep that mind. Little things like adding in a cool production logo, a long opening and closing credits. These are things that seem impressive but feel like hold overs from features. Get in, tell and economical story and get out. The shorter your film is the more of a chance it will get screened and the more opportunity you will have for it to be viewed by an audience. In the end isn't that the most important thing. For people to see an enjoy your film. Best of luck