look at how much more crown you get with the bridge hat...nice and beefy like a raiders. there's is more height/volume in it....that should be a dead give-away. also, the brim is curled more on desi's whereas the bridge hat is pretty straight till the rear of the brim. typically a brim curl will also give the illusing that the brim is shorter, which is why the bridge hat looks more 'hooded' than the one used on the 'death of mola ram' set.
the differences are quite slight of course......if they weren't, they'd fire the continuity director.
I see what you are saying, but I think it's the same hat. Look at the left (his right) top edge of the hat ribbon in the bridge pic. You can see that ragged, "peeling out" effect that appears on Desi's hats' ribbon. I think the effect of a lower crown you are seeing is a combination of perspective (the Mola Ram fight the hat is tilted back slightly, shortening the crown a bit by perspective), and the center dent being smashed in a bit more than other scenes (see other shots from above and behind Indy in that Mola Ram scene- you can see the stoved-in top and back) which could also lower the front crown by a fractions of an inch. If you measure them both out accounting for perspective, there isn't much more than maybe a 1/4" difference in the front crown pinch height between the two, easily accounted for by the smashed-in center dent and/or the perspective difference.
To me it just goes to show how different the exact same hat can look depending on the angle, lighting, conditions (hat bumps and crumples from set use) - I mean, I who would have thought that the dark, tapered-up looking hat seen in the cockpit scene is actually the same one in the Mola Ram fight scene? I never would have, had I not seen the cold, hard evidence Desi presented.