I would like to mask my background map using a shapefile representing a regional boundary. To do this I have read a spatial raster into Rstudio using read\_osm

```
library(sp)
library(tmaptools)
HB_map <- spData::nz %>% 
  filter(Name=="Hawke's Bay") %>% 
  tmaptools::read_osm(type = "stamen-terrain")

```

I have then imported my shapefile

```
libary(sf)
Regional_boundary <- sf::st_read("regional_boundary.shp")
sf::st_crs(Regional_boundary)= 2193 
Regional_boundary_sf_poly <- sf::st_transform(Regional_boundary, 27200) %>% 
  sf::st_cast(to="POLYGON")

```

I have a number of GIS data sets so I re-project my raster so it is in the same projection as my GIS data (i'm not sure if this bit is right)

```
test_map <- projectRaster(HB_map, crs ="+init=epsg:27200")

```

I then check the data projections are consistent 

```
crs(Regional_boundary_sf_poly)

```

[1] "+proj=nzmg +lat\_0=-41 +lon\_0=173 +x\_0=2510000 +y\_0=6023150 +ellps=intl +towgs84=59.47,-5.04,187.44,0.47,-0.1,1.024,-4.5993 +units=m +no\_defs"

```
crs(test_map)

```

+init=epsg:27200 +proj=nzmg +lat\_0=-41 +lon\_0=173 +x\_0=2510000 +y\_0=6023150 +datum=nzgd49
+units=m +no\_defs +ellps=intl +towgs84=59.47,-5.04,187.44,0.47,-0.1,1.024,-4.5993 

Now I apply my mask:

```
Library(raster)
test_map_mask <- raster::mask(test,Regional_boundary_sf_poly,inverse=FALSE,updatevalue=NA, updadateNA=FALSE)

```

And check the results

```
tmap::qtm(test_map_mask)

```

It all seems to work except the map colours no longer look like the original "stamen-terrain" but are instead different shades of orange". How do adjust the settings to make the map look like the original but with the mask?

Thanks for you help.
Kind regards,
Simon