Both ImageServer and MapServer
can provide imaging service rendering raster layer.
They are similar but different thingy.
1) MapServer
https://developers.arcgis.com/rest/services-reference/enterprise/export-map.htm
1.1 Map Server imaging example
Raster image .JPEG file
https://transparentgov.net:3200/googlemaps12/default?layer_id=0&layer=SilverRock_MasterPlan_29Nov2016_s200-images.jpg¢er_lat=33.66320688897262¢er_long=-116.27826137433512¢er_zoom=15&url=https%3A%2F%2Fgis.la-quinta.org%2Farcgis%2Frest%2Fservices%2FCommunity_and_economic%2FSilver_Rock_Master_Plan%2FMapServer&panto=0&overlayOpacity=8&overlayType=overlayType_image
https://transparentgov.net/json2tree/esri/server/folder.html?url=https%3A%2F%2Fgis.la-quinta.org%2Farcgis%2Frest%2Fservices&org=La+Quinta+CA&_center_lat=33.6634&_center_long=-116.31&_center_zoom=17&select_folder=29&select_layer=0
1.2) Map Server imaging example
Feature layer as static map image
1.2.1) Parcel boundary line and house number are soldering together as static image, not clickable
https://transparentgov.net:3200/googlemaps111/default?layer_id=2&layer=Parcels_House_Number¢er_lat=33.72098316215652¢er_long=-116.28153569675872¢er_zoom=17&url=https%3A%2F%2Fgis.la-quinta.org%2Farcgis%2Frest%2Fservices%2FPublicSafety%2FBaseMap%2FMapServer&panto=0
If user click static image, it will get vector data around the location clicked.
1.2.2) Parcel APN number and parcel line are soldering together as static image
https://transparentgov.net:3200/googlemaps111/default?layer_id=3&layer=Parcels_APN¢er_lat=33.72007742906516¢er_long=-116.28037698246429¢er_zoom=19&url=https%3A%2F%2Fgis.la-quinta.org%2Farcgis%2Frest%2Fservices%2FPublicSafety%2FBaseMap%2FMapServer&panto=0
Check more example:
https://transparentgov.net/json2tree/esri/server/folder.html?url=https%3A%2F%2Fgis.la-quinta.org%2Farcgis%2Frest%2Fservices&org=La+Quinta+CA&_center_lat=33.6634&_center_long=-116.31&_center_zoom=17&select_folder=14&select_layer=3
2) ImageServer
https://developers.arcgis.com/rest/services-reference/enterprise/export-image.htm
https://transparentgov.net:3200/googlemaps9/default?layer=Aerials%2FRedlands_Aerial_2002_2ft¢er_lat=34.099290178264475¢er_long=-117.19607773611396¢er_zoom=12&url=https%3A%2F%2Fgis.cityofredlands.org%2Farcgis%2Frest%2Fservices%2FAerials%2FRedlands_Aerial_2002_2ft%2FImageServer&panto=0
Tabs version https://transparentgov.net:3200/googlemaps911/default?layer=Aerials%2FRedlands_Aerial_2002_2ft¢er_lat=34.099290178264475¢er_long=-117.19607773611396¢er_zoom=12&url=https%3A%2F%2Fgis.cityofredlands.org%2Farcgis%2Frest%2Fservices%2FAerials%2FRedlands_Aerial_2002_2ft%2FImageServer&panto=0
https://transparentgov.net/json2tree/esri/server/folder.html?url=https%3A%2F%2Fgis.cityofredlands.org%2Farcgis%2Frest%2Fservices&org=Redland+CA&_center_lat=40&_center_long=-74&_center_zoom=17&select_folder=248&select_layer=-1