Offset after georeferencing of an old maritime map of Quebec

Question

For some time, I have been trying to georeference an old map of Quebec. On photo 1, there is the indication on the projection. Map from 1936-1937, with small corrections in 1946

I use the coordinate grid present on the map (Photo 2)

I tried many projections, many coordinate systems and in the best case I get an offset of several hundred meters on my georeferencing

I tried with :

• NAD27(CGQ77)/UTM zone 19N
• NAD27/ UTM zone 19N
• WGS84/ UTM zone 19N but without conclusive results

I must have missed a step, but I don't know which one.

Which projection and which coordinate system would you use to get the best result?

Answer 1

This is just using the screenshot image: (if can have a higher resolution will be more accurate)

WGS 84 / UTM zone 21N

Using QGIS 3.26.2 Georeferencer