We can also sorte out the mtexture when playing with the value of BG color and the Sm .
HERE is same difference when using the speculartiy map ( euh I used a diffuse map in this case i'll try it next time with another material with its own sm )

The BG color affect the brightness of the refelction and the image of back ground of course.
Sm will affect the type of the reflection .
You can see same difference between the images below..
I also used an hdri file ..

![BG color 10 " It gives a good wet aspect euh.."](/uploads/imported_attachments/gc3X_hhh.png "BG color 10 " It gives a good wet aspect euh.."")

If it can help those who asked the same question that I did YES i'll be glade to put all what I've learned up to now ..

I suppose that turning off the sun mean disable the physical camera (or the exposure), euh yes, because I've used an hdri file but I didn't enable the defaults lights under the global switches menu and neither adjust it in the reflect color under environment menu. it was just a little test to see how the specular map will work with artificial light sources .
Yes andy, i totally agree with , The GI color will only affect the brithness of the model's textures ( increase the amount of white when increasing the value of the GI color)
Here is an exemple below.

Vray version 1.48.91

Hello everyone
Thank you Andy for your posts and advices; excuse me for my english it's my third languange

After working on a house secen form model that i'Ve downloaded form google warehosue, here is some point that I want to share with you.

The specularity map when puted on highlight texture it gives a better reflectivity of artificial light on irregular surface , So bump map have a big part of standing out a realistic aspect of the material when combining with " specularity map " .

You're right andy for the dispalcement the bump map can replace it most of time I think and it takes too much time to render the scene .

The texture I used is downoladed from "free low resolution arroway texture" I guess that the high quality one will gives much more realistic image . ( of course am talking about Stone texture )

You can see just under the light source a good effect of bump and specularity just inside the house.

less is the artificial brightness less is the quality of the result . about the sun light I Think that its hard to get that effect without high quality texture. I'll try that and share the result .

I set the exact size of texture like in the info form the website, I enabled the displacement and put the bump map and have given it 1,96 valu wich its corespond to 50 mm (converted into inches)always took the info from textrue info of website .

I had worked for hours to get the aspect that i've seen in the demo in this site : http://www.arroway-textures.com/catalog but still don't get it .
Can we get this result with Vray for sketchup ??

I don't think that the reflection filter is used for the specularity; this is what it's said about it in Vray for sketchup " manual "
Reflection Filter :
The filter color is used to apply color to reflections. You can see that by changing the filter color
on each of the renderings below the color of the reflections change. The magnitude of this effect
will change based on the strength of the reflections themselves. In the case of materials which are
very reflective, filer color may be an effective way to change the object’s appearance.

About the reflection glossiness :
You don't always get clear reflection from reflective material. Objects like matte finish metal, wood and some plastic materials do not reflect the lightsource clearly due to its uneven surfaces. This is because the
uneven surfaces create many reflecting angles for light to bounce around. So the highlight is not as sharp if compare to reflection from smoother surfaces. The best way to create this kind of rendering quality is playing around the setting of both Highlight Glossiness and Reflection
Glossiness

The specularity map is used to reflect the light form bright object "lightsource" and sun and let only some part of the material " or object that we have affected it " reflect them because of the iregularity of the surface like in concret .

In this tutorial of chaosgroup Material part 2 he used the reflectivity map and set it as a texbitmap in both highlight glossines ans reflection glossiness . and for the the wall texture he used a fresnal for the reflectivity glossiness .
http://www.youtube.com/watch?v=ygvBfeK2HHY&feature=mfu_in_order&list=UL

Does someone can expaline to me where can i put exactly the speculartiy map and why ?

Thank you so much Andy.. i'll try that this evening and show you result !

Hello everybody
I just want to know if it is possible to add a specularity map of concrete texture ? I have the three maps that I need : the diffuse map that i added directly in my sketchup model and also the bump map that i added in " MAPS" of vray editing materil tab .. I stil don't know where should I add the specularity map !!! there is no tab of specularity, doest it has another name that it corespond ??

thousand thanks

thaks for the liens ecadurio