Well, first, to be clear, I was not matching this reference photo. I put my lights in generally the same location, and I liked the camera angle, but I made no attempt to match this particular R2. This R2 was actually in its 3 leg position at the time of the photo, and mine is standing upright, as well.
As for the look: There are several R2's made of different materials. The original ones were aluminum, painted with white auto paint (the closest modern match is DuPont Spectramaster Light Neutral LS015K), while for subsequent films, several fiberglass moulded versions were used. Legs and bodies are frequently interchanged. Additionally, there are vastly different levels of dulling and weathering used such that there is a nearly infinite variety of looks for R2's body, and if you scour any number of references, you'll see it all over the map. The R2 in my shot matches the one I took my reference photos from, and it's somewhere in between, shiny-wise. It is an aluminum frame with auto paint. The appearance in my render is hugely dependent on lighting, and in subsequent renders, you'll see it appear as nearly matte, to much shinier, just by its nature. Go to the gallery at
www.astromech.net and you'll see a full range of looks for R2. Unless you're matching a specific combination of legs/body/dome, there is no "definitive" R2, so I chose to match the one I actually worked with.
_Mike
I think the one in the film was fake. 
- By Mark Bell
- By Mike Amos 20251018183343
- By Blanchett