Hey Barrie,

This Function should give you an idea about the Image sizes used in the Salient Theme : 

if (!function_exists('nectar_add_image_sizes')) {
    
    function nectar_add_image_sizes(){
        add_theme_support( 'post-thumbnails' );
        add_image_size( 'portfolio-thumb', 600, 403, true ); 
        add_image_size( 'portfolio-thumb_small', 400, 269, true ); 
        add_image_size( 'portfolio-widget', 100, 100, true ); 
        global $options;
        $masonry_sizing_type = (!empty($options['portfolio_masonry_grid_sizing']) && $options['portfolio_masonry_grid_sizing'] == 'photography') ? 'photography' : 'default';
        if($masonry_sizing_type != 'photography') {
            add_image_size( 'wide', 1000, 500, true );
            add_image_size( 'wide_small', 670, 335, true );  
            add_image_size( 'regular', 500, 500, true ); 
            add_image_size( 'regular_small', 350, 350, true ); 
            add_image_size( 'tall', 500, 1000, true ); 
            add_image_size( 'wide_tall', 1000, 1000, true );
        } else {
            //these two are still needed for meta overlaid masonry blog
            add_image_size( 'regular', 500, 500, true ); 
            add_image_size( 'regular_small', 350, 350, true ); 
            add_image_size( 'wide_tall', 1000, 1000, true );
            add_image_size( 'wide_photography', 900, 600, true ); 
            add_image_size( 'wide_photography_small', 675, 450, true );  
            add_image_size( 'regular_photography', 450, 600, true ); 
            add_image_size( 'regular_photography_small', 350, 467, true ); 
            add_image_size( 'wide_tall_photography', 900, 1200, true );
        }
        add_image_size( 'large_featured', 1700, 700, true );  
        //add_image_size( 'disable_crop', 800, 800, true ); 
    }
}

Be.st