Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3825845.

This was inspired by BrockLockers thing to help my wife with painting compositions. I found Brocklockers thing when printed not quite true in proportion to how I understand the Golden Ratio so I recreated my own in Fusion 360 (This may well be a Photography proportional implementation that I am not aware of or my slicer\printer is doing silly things) .

I have included a plain template and one that includes the Golden Spiral which may be better for Designers. The things are only meant as an approximate guide\aid to composition.

You may have to uniform scale the thing to suit various build sizes.