How to get videos to fit screen in photoshop video editor

In Photoshop video editor, try selecting the video layer, then use the 'Free Transform' (Ctrl+T) option. Hold down the Shift key while dragging the corners to maintain proportions. Crop excess using the Crop Tool if needed

Yes, Trevor’s right, Edit > Free Transform will let you resize that video by dragging transform box handles, just as you can with a still image layer. One tip: It can be a challenge to make it fit exactly the edges of the video frame by dragging, but as long as the Free Transform box is active, in the options bar you can just type the document width in pixels into the W value, and then when you press Enter/Return, the layer is precisely resized.

I share Trevor’s concern about the canvas size, 4096 x 2160. Is the intention to create a standard 4K video? Because if it is, the pixel dimensions should be 3840 x 2160 px. There are some confusing reasons why:

In the New Document dialog box (see below), Photoshop offers two different 4K presets next to each other: UHD and DCI. The one you want is UHD 3840 x 2160 px. This is the 4K standard that is used for all new TVs, computer displays, and mobile devices.

The other one is DCI 4096 x 2160. Even though it has more horizontal pixels, this is actually the same frame aspect ratio as UHD,  so the problem is it will look distorted on a current TV/computer/phone. The reason? The older and now less common DCI standard uses a non-square pixel aspect ratio. It may look OK in Photoshop, but that’s because Photoshop is applying the View > Pixel Aspect Ratio Correction command to correctly simulate how it would look on a DCI system.

If your intention is to show the final project on a current consumer TV/computer/phone, it’s probably worth starting over from a document set up at UHD 3840 x 2160 px,  1:1 (square) pixel aspect ratio. I think if you wanted to continue with the current document you could, but then at export time you would have to know how to set it up to correct the pixel aspect ratio so that it renders to the UHD frame aspect ratio and pixel dimensions.

Hi Lacie.  You are using a 4K DCI 4096 x 2160 timeline.  The clip we can see looks too be about 1080p (1920 x 180). Do you want that clip to fill the frame?  It is going to lose quality if you stretch it out but only in relative terms, like if viewed on a 4K screen with proper 4K clips to compare with.

I don't use Photoshop for video, but I think if you click on that clip in the timeline, you'll see handles similar to using Free Transform in Photoshop, and be able to stretch the clip to fit the frame.  One issue you will have is that your timeline has a different aspect ratio to a standard 1080p clip, so you'll lose a tiny bit from the top and bottom if you stretch to the full 4096 pixel width.  We can already see evidence of that in the right most clip of the aircraft, which is showing transparency either side.

So your options are to start again with a 1080P timeline. But that depends on what size the other clips are.  Do you know that?

Have a black border around the smaller clips.

Or stretch to fit the frame.

One thing I am wondering about, is why you chose the 4K DCI timeline which Wikipedia tells me is a cinema projection size.