#SciFund Challenge Class

Video storytelling made easy for scientists

Part 12: Editing - the Basics

In this and the following two parts of this guide, we'll be walking you through how to edit a video together. Before you actually get going on your own edits, please do read through these parts first. We'll be getting to your own edit, in PART XXX (Your Rough Cut)

Manuals for iMovie and HitFilm 

In the next few sections, we'll be walking you through the art of editing, including many how-to videos. However, in case you want to do something that we don't cover in our materials, we did want to note that there are extensive online manuals available for both iMovie and Hitfilm. The manuals won’t give you any guidance on the craft of editing, but if you have an idea for something that you don’t know how to pull off in the software, reading these may help.

The Rough Cut - the Rough Draft of Your Video

Now that we have a rough assembly of our story on the timeline, we can begin to think about some basic editing principles to help tell our messages and perhaps even help elicit those potential emotions that we noted on our script worksheet.

The craft of editing is as much about how and when to make cuts in your footage as it is about learning to use the tools in the software. Before getting started, we wanted to paraphrase something that editor Walter Murch said in this video.

Like he said, editing is a lot like dancing. Someone can explain the rudiments of dance to you, but to learn how to dance you really just have to dance. Editing is the same way - it takes practice.

The point of this section is to increase your "visual literacy" and to expose you to a sampling of the ways that editors think about things. With your very first video, don't worry about applying all of the following ideas - in fact, with these short science videos that we're making, it wouldn't be possible to do so. But keep an eye out - spotting opportunities to employ some of these ideas could be the key to taking your video from good to great.

The process of editing a rough cut of your video is a lot like writing a paper. After laying down an overall story, several successive passes are made over it. Each time you fine tune and alter a different part. Here is a general summary of each pass in the order they should be done:

  1. Order – The order that you show things in your video. Linking all the video you have together on the timeline
  2. Timing, speed, & rhythm – The speed that those clips are shown in your video
  3. Add transitions, effects, and other material (photos, animations)
  4. Add music and sound effects

So let’s get started editing our videos…

Shot Order

Just placing one image after another implies a connection between the two things in those images. Sometimes you can use that knowledge to help increase dramatic tension. Watch this video to see the point demonstrated:

Timing, Speed & Rhythm

  1. Timing involves showing relevant images that match the audio track (script or music). This step will have most likely been done during the rough assembly stage. Remember you can also cut up your script to make longer pauses if you need more room for your clips (as long as those pauses sound natural).
  2. Speed is how quickly shots are shown from one to the other in a sequence. When a video cuts from one image to another quickly it can feel more energetic, raising the dramatic tension. Leaving a shot on for longer can achieve the opposite effect. Here is an excellent description of that idea, using the scene in The Empire Strikes Back where Luke tries to use the force to raise his X-wing out of the swamp (the link will start the video at the relevant point. Watch to 5:20). The DeLorean video mentioned many times previously in this guide also uses this trick - shots of work on the car get shorter and shorter until the car is ready.
  3. Rhythm is specific to every shot and is dependent on the context and the content of the image. Every shot has a lifespan of its own. With experience, you can tell when a clip needs to be cut because it just feels right. Here is a great demonstration of that idea (watch to 7:43). Noticing when a clip plays for too long can be difficult, especially if you have been editing a project for a while, or you really like a particular shot. It’s best to get another person’s opinion on it. Decisions on speed and rhythm are best made when a clip is in context of the other clips around it; play through a sequence several times, taking a look at what is working and what isn’t.

The bottom line here is that timing, speed and rhythm are three things you can think about when making a cut to help guide your audience through your story.

Cutting on the Action

As we saw in the very first exercise of this guide, we can cut on the action to help an edit feel more natural. This is most easily done when we have the same action, shot from two angles. Watch this to see cutting on the action demonstrated (watch to 0:57).


Transitions describe how a clip cuts from one to another in your video. Generally speaking, you can order types of transitions by how frequently you should use them in your videos, from most to least used:

  1. Straight cut – Take a look at any TV show or film and the majority of cuts in there will be straight cuts. The shot on screen just changes from one to another. How well a straight cut works and how natural it feels will depend on the timing, speed, and rhythm described above. Here's an example:
  2. L cuts & J cuts
    1. L cut – An audio based transition. Audio from the current clip carries forward into the next. Here’s how to apply an L-cut in HitFilm. Here’s how to apply an L-cut in iMovie.
    2. J cut – Another audio based transition. This is the reverse of the L cut. Audio from the next clip is introduced while we can still see the current clip. Here’s how to apply a J-cut in HitFilm. Here’s how to apply a J-cut in iMovie.
  3. Fades – Fading to or from black or white draws direct attention to the cut and can be a good way to add impact to a shot. Here’s how to apply a fade in Hitfilm. Here’s how to apply a fade in iMovie. Also, take a look back at the DeLorean video and see how they use fades to and from black to add impact and mystery. Generally, fades can also help imply several ideas and feelings, depending on the content of the shots being faded:
    1. Time passing – nostalgia, looking back
    2. Things appearing – revelation, mystery, questions
    3. Things disappearing – hidden, mystery, running out of time
    4. Eyes opening/closing – new, start, end, finality, previously unseen, new perspective
  4. Jump cuts – This is a straight cut between two clips from the same shot size and angle (ie look extremely similar). They can be used for two purposes:
    1. For visual effect: This type of jump cut has a rich history in film. An ‘accidental jump cut’ due to a camera malfunction is often cited as the birthplace of editing as a concept. To find out more watch these videos: for iMovie and for HitFilm
    2. To remove information: These are used to cut out mistakes or irrelevant information; they are about efficiency in a way. Due to the proliferation of vlogging and youtube where jump cuts are common; norms are shifting and they have made their way into factual films and modern cinema. To see a masterful use of jump cuts in a factual film, watch this section of the “Fog of War” by Errol Morris. Notice how he doesn’t hide the cut behind B-roll, although he uses B-roll later. A decision has been made that prioritizes seeing McNamara’s face over cutting away to B-roll. The jump cuts feel intentional and add impact to what he is saying. But if a jump cut doesn’t feel intentional or like a stylistic choice when watched, they can look amateurish. Here’s how to make and deal with jump cuts for information removal in HitFilm and in iMovie.
  5. Cross dissolves – These also draw direct attention to the cut itself by mixing the current and next images together for a brief amount of time. This type of transition should be used sparingly. It is good for emphasizing a direct connection between the two images being mixed together or implying a passage of time like the training montage in Rocky. People often use cross dissolves if they aren’t comfortable with a straight cut, however it is often better to review the timing of the cuts and/or trying J/L cuts before resorting to a cross dissolve. Here’s how to apply a cross dissolve in HitFilm. Here’s how to apply a cross dissolve in iMovie.
  6. Wipes – These come in different styles stars, shapes etc; the most basic is the straight wipe from one image to another. They can appear dated or over stylize your video so most of the time they should be reserved for Star Wars movies and home videos only. But if you think the style of your video suits, then wipe away! To give you a sense of what wipes look like, here are the wipes in Star Wars.