Welcome to TVPaint Community forums !

I've been using TVPaint for a while, but I still don't understand the point of the image layer. What can it do that the anim layer cannot?

- you can drag in/out the start/end handles to make it shorter/longer in the timeline without confirming your intention,
by setting your wanted mode, and applying in the increase/decrease layer's length panel.
(anim layer : click&drag + set the repeating mode + click Apply, image layer : click&drag, that's all.)

- when an image layer's length is f.i. a range of 50 frames, you can draw anywhere in the timeline
between the start and the end without having to check the autobreak option Off,

- at last but not least, backward compatibility (if Image Layer will disappear in the tvpa code,
what will happen when a user will try to load an old project with Image layers inside ?

Image layers are suitable for still BG, and sometimes Overlay,
otherwise, and as usually, if you don't need it, don't use it.

- you can use it as a sketch layer; I always scribble auxiliary lines or perspective construction in there
- if you need to render a loop and need it repeated, you can easily elongate an image layer to the desired tme (otherwise the export window will not let you enter a frame number big enough)

Thanks for the replys