[Helmut10001]

San Francisco looks nice, but there seems to be a problem with the projection in some of the sample images. It looks as if it isn't UTM but a global sphere projection, which isn't suitable for local renders. It's suspicious that the word 'projection' isn't mentioned in the Readme.

[jasongill]

This is an artistic project to make a fun and artsy poster, so it's not at all "suspicious" that the map projection is not critical to the artwork.

It also appears to be open source, so perhaps you can open a pull request with your improvements based on your cartographical experience.

[Helmut10001]

You are absolutely correct. Suspicious was the wrong word and I did not mean to criticize the author or the work.

[jlarocco]

It looks like the final images have some kind of vignetting to make the corners and outter edges fade away. Probably grabbing OSM tiles and doing some image processing.

Looks neat!