Image won't show: Image data of dtype object cannot be converted to float

Question

I am trying to get python to read a geoTIFF image but am having trouble trying to get the image to show.

import rasterio as r
import numpy as np
import matplotlib.pyplot as plt    

FNF=r'D:\\Iceberg data\\RADARSAT\\RS2_SLC_geotif\\roi20m_RS2_20160415_153940_0004_FQ13_HHVVHVVH_SLC_470697_4660_12996414_Geo.tif\\'
    raster = r.open(FNF)
    
    print(raster)
    raster.bounds
    raster.height
    raster.width
    raster.transform
    raster.get_transform()
    raster.tags(1)
    xmin=raster.bounds[0]
    ymax=raster.bounds[3]
    raster.read(1)
    
    fig = plt.figure(1)
    plt.title('SLC image')      # this defines the title 
    plt.imshow(raster)

I get the error with imshow. What am I doing incorrectly?

When I do {i: dtype for i, dtype in zip(raster.indexes, raster.dtypes)} I get float32 out.