Is there an easy way to have a light affect specular lights only.  I am lighting a scene with HDRI, but I lose all of the specular shininess.  Is there a way to have a seperate distant light that will only affect specular?  Thanks.

In an area I dont know much (anything) about. Specular in my use of words is reflectivity. This obviously can be adjusted in the shader, but, if the HDRI plays up with it, perheps you could bring in that other light and set it to shine on only your selected item.

See the general tab for a bulb light.

bwtr

When I refer to specular, I mean shininess.  Reflections work fine with HDRI because the HDRI can be used as the reflection map.  The reason for my question is that I am more used to the way things are done in Poser.  Poser allowed you to create a light that affected specular highlights only.  I can't seem to find a comparible feature in carrara.

Hi webdefender, Carrara doesn't have Highlight only light. However, you can acheive the same effect in Carrara's Shader Room. By default the Highlight channel has a Value slider in it with a range of 1-100. All you need to do is exchange that Value slider for the Value slider with the range of 1-10,000. Then, increasing the specularity of the object is simply a function of working the new Value slider. Mark

Mark your reply confused a bit, however I found Highlight and Shininess in the (printed) manual p350/351.   Webdefender, does that manual reference make an answer for your query clear?

Its page 677(687) in Help.

bwtr

I have the pdf of the manual since I bought the download version of Carrara.  I have read the manual about shininess, but what I want is for a light to affect only the specularity and nothing else.  I tried the suggestion about the shader but I can't seem to get it to work.  Should it work with all types of lights, ie. bulb and distant?

Pretty sure you can not use the distant light. Bulb should be ok.

As I read that stuff in the Help/Manual your 'specularity" is made up of those two parts.
ie you can't have specular effect without both?

((English is very confusing at times--I wish I was bi-lingual!)

bwtr

Short anser is no. In Lightwave and other programs you can specify wether a light affects specular only or diffuse only, or both. This can be handy at times, allowing you to have a fill light that does just that and doesnt create hot specular highlights. Sometimes you want an object to have "false or extra" highlights, in Carrara you are also going to get increased diffuse shading. In Carrara every light affects both specularity and diffuse shading. Hopefully this is something that could be added in the future, as I have relied on it more than a few times in Lightwave.

Lost me I guess?  As I see it in Carrara you can have this Carrara two part specularity assigned to one object and have one specified light only lighting the "specularity" of that object?

The rest of the objects relating to other lights as per each objects particular settings?

Sorry if I am not with you--it's new learning for me.

bwtr

Here's an example of how to "brighten" specularity in Carrara with the Shaders. While Carrara doesn't have that control via the lights directly, you can acheive the same effect by increasing the Highlight channel beyond the default 100. Additionally, if you use the Add operator, you can throw in some color to. Now if brightening is not your goal just let us know and we'll see what we can figure out! :D Mark

Highlight and Shininess set as suggested by Mark (and Manual) to RH sphere.

2 Bulb lights--default settings only.

bwtr

Yes it can be done with shaders--to a degree. You still couldnt put two lights above a plane side by side and have it work. Imagine a shiny plane with two lights above it side by side. Lets say that you dont want specular highlights from the light on the left, you just want it for some more light. Reducing the specularity in the shader for the plane will not remove the specular highlight from the left light, it will only increase or decrease both equally. So now you will have two hotspots on your shiny plane. I have found this to be a nice feature in Lightwave, especially when doing outdoor scenes, say with a logo floating above an ocean. The distant light wasnt lighting the logo enough, but the ocean would look great. If I add another light it also affects the specularity of the ocean. Selective lighting can solve that too, but a switch that specifies if a light affects specularity, diffuse or both would be nice. Also, I have run into scenes where all I wanted was a bit more specularity--but not brighter specularity that already existed. With a switch I can throw another light in there, not worry about the diffuse getting too bright and place that light where I want to get another highlight. Again, it can be worked around, especially now that Carrara does have selective lighting options. But IMHO it is much easier and quicker to have a switch for the light dialog.

You arent lost. You have it right too. With Carrara's new selective light list you can do it. Still, it is much easier to do with a switch at the light level. You still have the option to do it at shader level, which I do quite often anyway. But the example I mentioned above is a reason that I like it. Simple and quick.

Quote - Lost me I guess?  As I see it in Carrara you can have this Carrara two part specularity assigned to one object and have one specified light only lighting the "specularity" of that object?

The rest of the objects relating to other lights as per each objects particular settings?

Sorry if I am not with you--it's new learning for me.

Attached Link: look here

An old raydream trick that still works in Carrara is to set a bulb in a semitransparent reflective sphere with highlights. If you make 2 of these rigs and vary the highlight , the highlight recieved from these light spheres will vary accordingly.

I often add just one distant light to a scene I'm lighting with just an HDRI background image to give my objects that certain highlight I need.

www.youtube.com/user/ShawnDriscollCG

Thank goodness for top search, this saved me a brand new re-post. 

Jrabbit, since this post is pretty old, would you still have the link to the bulb technique you linked?  The link appears dead, and just wanted some specifics on settings.

Thanks,
Boeing

If anyone is interested in a function like this and you're a Shaders Plus customer, drop me a line off list. I have a beta Shaders Plus that I can share that does this. It's a new lighting model where you can control the specular and diffuse contribution of each light and adjust the GI and ambient light.

Regards,

Eric Winemiller
Digital Carvers Guild
Carrara and LightWave plug-ins

 Oh man, that could be a life saver. I'm interested.

Oh wow, count me in...interested for sure.

Here is what I got using everybody's suggestions above...I just can't seem to get her to look realistic though..something missing. 

I used HDRI lighting with Carrara 6 Pro, added a spot light and had it point only to V4.  I then fiddled with the highlight and shine using a mix of specular map and cellular in the highlight channel.  I then added translucency to about 20%.