Attached Link: http://www.renderosity.com/messages.ez?Form.ShowMessage=2073866

First of all, thanks to Stewer for writing this tutorial. I am not at all proficient with materials room and I gave it a try with plugging the nodes as described as best as I could. I didn't use the HDRI map because I don't quite understand it yet, instead I used the regular image with sphere map for the reflection. Even then, I must say, this is probably the best reflection that I got from all the materials I tried. (and it looks even better if I use the white plane trick, but takes way longer to render though)

My question is, the part about making a HDRI map, can this be made by using any type of image? I tried to create one using the HDRShop and this is what I did, open an image, adjust the exposure to one image for +2 and another one at -6, and save each image as a Low Dynamic Image Tiff. Finally, I tried opening the image in materials room, but it gave me an error message saying it's not recognizable.
Also, when I open any image in HDRshop, it says to specify camera response curve for LDR image, do I just accept the default setting and click ok?

Lastly, what would be the best method to change the color of the car for this method?

You can't blow up existing jpg images to HDR. You need an HDR image to begin with or you can take multiple photographs at different exposures if you have a camera that allows that.

Ah, thanks. See, I knew I had no idea what I was doing in HDRshop. :)

Okay, so now I have a HDR image, how would I go about converting it to the 8bit LDR tiff? After changing the exposure, do I just save it as a LDR tiff (which still won't open in poser)? Or do I export it to photoshop and save it there?

Sorry if I am asking dumb questions but I am really confused about this.

Well, I am not sure if the images were exported correctly, but, regardless, it did make whole lot of difference compared to the regular sphere mat. Rendering took much longer (actually it seems to be stuck at certain spot even though it's rendering the similar surface). But I am really happy with the results and thanks again to Stewer for that tutorial.