Absolutely. You should size the images according the highest resolution screen, projector etc. the video will eventually be viewed on. A good approach is to make a very high quality 'master' of say 4K, (3140 x 2160 pixels) and render out to various end sizes like 4K, 1080P (1920 X 1080 pixels) etc. If you know for certain that the final product will only be shown on one device, then size for that.
While Photoshop can do this, other applications like Proshow Gold are better. A big disadvantage with Photoshop is that it is difficult to sync an audio track to the images for instance.