“A cut, the most basic type of transition, is a transition with no duration; when one shot ends, another one immediately begins, without any overlap. All other transitions gradually replace one shot with another; when one shot ends, another one gradually replaces it. There are three very common video transitions used that occur over time: fades, cross dissolves, and wipes.

  • Fade-out: This begins with a shot at full intensity and reduces until it is gone. A fade-in begins with a shot at no intensity and increases until it is full. These are the common “fade to black” and “fade up (from black)” transitions.
  • Cross dissolve: This involves two shots. The first shot fades out while the second shot simultaneously fades in. During the cross dissolve, the two shots are superimposed as they fade.
  • Wipe: This is where the screen splits, moving from one side of the image to the other to gradually reveal the next shot. It is more obvious than a fade or cross dissolve.

Final Cut Pro also comes with two audio transitions: a +3 dB cross fade (the default) and a 0 dB cross fade.

  • Cross Fade (+3 dB): Performs the same operation as Cross Fade (0 dB), but applies an equal-power ramp to the volume level, rather than a linear ramp.

    Note: An equal-power ramp uses a quarter-cycle cosine fade-out curve and a quartercycle sine fade-in curve. As a result, the volume is maintained at a constant level throughout the cross fade.

  • Cross Fade (0 dB): Fades the first clip out, while simultaneously fading the second clip in. This effect applies a linear ramp to the volume level. As a result, the volume level dips in the middle of the cross fade.

Each cross fade results in a different audio level change as the transition plays. Your choice of cross fades depends on the clips you’re transitioning between. Try one, then try the other to see which sounds better.” – documentation.apple.com/en/finalcutpro

Videos on Transition Techniques:

Video on exporting:
What file formats do you set Video to when exporting a file for youtube?

What size do you want the file to still be HD quality?