Quick tutorial on how to make a basic gif/video from a photo sequence. Shoutout to Kyser Lough for teaching me how to do this, since I used to manually align layers like a scrub and this method allows Photoshop to automatically line them up, panorama style.
First, open up Photoshop. Go to File>Scripts>Load Files into Stack...
This window will pop up. Click Browse, and select all the photos in your sequence.
(Click the first one, shift+click the last).
Then Open the files.
Because the frame itself is not static, I didn't select Attempt to Automatically Align Source Images.
An example of a gif where I would select this is the Pitching gif, which you can read my tutorial for.
In the Layers Panel (bottom right), select all the layers. Then go to Layers>Arrange>Reverse.
If your Timeline is not already open (bottom panel in the screengrab above), then open it via Window>Timeline. Click Create Frame Animation.
Click the 4 bars at the top right of the Timeline panel, and select Make Frames From Layers.
In the Timeline panel, click the first frame and shift+click the last frame to select all frames. At the bottom of one, click the down carrot after "0 sec." to set your frame delay rate.
At this point, if you need to, you can add correction layers (curves, white balance, etc.), add a watermark, and/or crop and resize your image. Otherwise, it's ready for export!
For gifs, go to File>Export>Save for Web (Legacy) and adjust the settings to your preferences for saving.
For mp4, go to File>Export>Render Video.
Pro-tip: Twitter .gifs must be under 15 MB and Instagram videos (mp4) must be at least 3 seconds long! If you need to duplicate all your frames, highlight all of them, then click the little icon at the bottom of Timeline that looks like a sticky note.