Ramachandran plot Phi(ϕ) Psi(ψ) dihedral angle Convention for Zero, Positive and Negative value- old and new

Update: possible duplicate: What is the precise definition of Ramachandran angles?. Question modified.

G.N. Ramachandran et al, in their own work (PMC) (DOI), did not used phi(ϕ) and psi(ψ) as we use today. They used phi(ϕ) and phi-dash(ϕ') defined as follows:

The conventions we have adopted for the standard configuration ϕ = ϕ' = 0°) and for the positive sense of rotation for the two angular parameters ϕ and ϕ' are indicated in Fig. 1.

Where Fig. 1 is:

Also they had adapted a very different values, 0 to 360 degrees for ϕ and ϕ'. They provided the Ramachandran plot like this:

This looks very different from the Ramachandran plot we see nowadays because:

1. This (Ramachandran's original) graph looks flipped from todays.

2. The zero degrees value of present day is perhaps different from Ramachandran's Zero degrees. Because the current day zero degree correspond to Ramachandran's 180 degree (of original graph).

So my question is basically:

On todays convention; how we define the zero value, positive value and negative values of phi and psi dihedral angle? and how does the new and old convention relate?

Prior research:

I did not find anything on intensive internet search. I got one graphic without any reference

I am doubtful about this diagram because its Zero degrees seem to be the zero degree of Ramachandran's original plot.

Many thanks in advance

Update: As the user @Buck Thom said

The meaning of angles with value of zero is the same.

But sill I looked both old and new graph and found what is labelled as 0 degrees in the new graph, has been labelled as 180 degrees in the old graph as follows