Wish some help to improve render of swiss demining machine

Hi there,
I am currently working on a project of Swiss demining machine.
The final image will be print on a white paper, and only white background is required.

I would like to make this render much more realistic, but my skills are at the limit here.
I’d like any feedback, tips, ideas , suggestions, etc. to make this picture yet more realistic.
I know these are a lot of little nuances that make a better picture , unfortunately, I am not
not yet familiar with all these little details, and that’s where I hope you will help me.

I created a very low poly model so you can see how I did it.
You can of course change anything you want, as long as it improves the image.
But please try to stay as close as possible to the original.

The Shaders are essentially based on this BlenderCookie tutorial :

The image of the complete machine (high poly model, which I am not authorized to share).

The low poly model with shaders and compositing.

Rendering from the low poly model.

You will find some reference images here.

If you speak french, you will find the same question here:
If you prefer german, this one is for you:

Thank’s in advance.

The machine high poly image is outstanding. Really, really well done. Was it done in Blender? And if so, could you say what extra add-on tools aided the effort.

Only one add-on was used to import the files in STL format.
The swiss “non-profit Foundation Digger” gave me the STL files, and I have to make the render.
Because it’s a “non-profit Foundation” which really saves lives, I would like to achieve the better result.
I think it’s allready pretty good, but I’m sure it could be better. I just don’t know how.

If you want product presentation you hit a certain spot in the center congrats !.
If you want more realism then thats another spot.
I mean a whole bunch of people like that style (like in product photography), but for real such lightning isnt real.
So if you want to go for more realism then you need shadows from a sun (or use a flat square cycles light emitter).
Then you will need ground too i think.

Also more realism you can get by setting a focus point of the camera (read about camera focus in blender).
You can do this in the main camera options. I’d prefer to use an empty as focus target (so you can more easily move it around).
Dont defocus to much, only a little a tiny little.

Also its much white on white, well you know what i mean, its not bad but think if you want that or not, i cannt play with the model, but i might be worried that it dissolves in the the already white paper.

Is that “compatible” with a “studio lighting setup” ?
For example, I saw these videos :

And this one is pretty unusual, isn’t it ?

You definitely have the basic model of the machine … which is, itself, a fairly “boxy” thing, painted in layers of tough industrial coatings. You could add things to it, like the rivets on the side in the right places. But, basically, anyone who’s trying to sell the thing is going to want a good, clean representation of it that looks “spotless” (like this machine will never again be, once it gets into the mines). The lighting should be matte and even, like the paint. There will need to be slight edge-defining specularity, especially where brightly-colored things are adjacent to darkly-colored things, but, “this is not a new car.”

Be sure to work closely with your printer. Choose Pantone colors. Ask them early about what characteristics the image needs to have in order to look good on paper in whatever CMYK (not RGB!) process they will ultimately use.

Every single screw is allready modelised. There are no rivets at all.

Thanks for the color advice, I will make some tests.

I made some tests with HDRI (and only HRDI, without any other light).
For me it’s just different, but neither better nor worse.
I don’t find that the realism is more obvious with HDRI, as with my studio lighting setup (down right).
What do you think ?