Creating curves from points with pen tool

Wow! Thank you so much guys, I never expected so many responses! Definitely will be giving all these methods a go 🙂

You can do this with regular Paths. Drag an ellipse out from each of the corners, so that the edges are tangent to the ellipse (all on one Path):

Use the Direct Selection tool to select the corner point and the two points on the ellipse not touching the edges:

and delete them:

Finally, use the pen to connect up all the orphans:

Unfortunately, "Fixed Size" isn't good for dragging out shapes from the corner, and these are not "Live" shapes.

IMO it would be easier to create curved lines from small straight diagonal lines that are the same length.  I would draw out  guide lined drag our your  shape with the pen tool that contains all straight lines. Then switch to the curvature pen and add anchor point in the middle of the diagonal corners and curve the lines.

Hi

To do that you would need to create two points at each corner. There is no straightforward way in Photoshop. A kind of workaround is to convert the path to a selection, smooth the selection then convert back to a path. However it is rarely accurate.

In Illustrator it is straightforward by selecting the shape and clicking A then dragging a live corner point

Dave