Can anyone please tell me a way to prevent objects receiving shadows in Poser 8? I can stop objects from casting, but not from receiving. I want to stop plants casting shadows onto a cyclorama background.

TIA

If it is a background or a flat plane with an image_map, go into the Material Room and redirect the image_map to the Ambient_Color of the PoserSurface and set it's value to 1.  To see the image in preview mode, maintain the connection to the Diffuse_Color but set Diffuse_Value to 0.

Poser can't do this on a selective basis as far as I know.  There may be a way to obtain this via material but I haven't heard of it.  Even if the backdrop is set to be excluded from raytracing it will (surprisingly!) still catch shadows, even with raytraced shadows, whether or not you are rendering with Indirect Lighting enabled.

Oops, I had forgot about Alt_Diffuse.  You get this (maybe what you want):

I appreciate your amazingly fast response, but that seems to stop the objects taking any light from the scene at all - even in a night scene, the backgrounds are now really bright. Any idea how I can resolve that please?

That's what Alt_Diffuse does, it makes the color shading ignore the lighting entirely.  Ambient will do something very similar (actually it will make the surface emit light when rendering with Indirect Lighting with non-zero Ambient_Value).

Quote - Can anyone please tell me a way to prevent objects receiving shadows in Poser 8?

I don't know how to do it in Poser, but you might be able to cheat. Render two versions of the scene. One version with everything except the item you don't want shadows for, and another version with only the item you don't want shadows for. Save them in a format that supports an alpha channel, like PNG, then compose the two parts as layers in a paint application.

Attached Link: cyclorama gradient

This isn't anything fancy, but I use it frequently to avoid having an -ahemmm- embarrassing  shadow on the backdrop wall of the Cyclorama, while retaining the shadowing on the ground.  I thought someone else might want to use it. ^^ 

demo using a mucho-mojo'ed Cyclorama;  notice that the huge tree's shadow fades away as it approaches the backdrop wall:

Hotlink is for the gradient image.

Provide a screencap of your scene.

Quote - This isn't anything fancy, but I use it frequently to avoid having an -ahemmm- embarrassing  shadow on the backdrop wall of the Cyclorama, while retaining the shadowing on the ground.  I thought someone else might want to use it. ^^

That's a pretty clever trick actually.

i think all those trics can be done in photoshop. you just need to turn them up in the code.

for example
-make object invisible to IDL
-make object invisible to reflections

we have invisible to raytracing. if we would have seperate options we could do even more tricks.

Actually I tried that thanks, but as I expected, the backdrop colour changes when there are no other objects in the scene.

 

Quote - > Quote - Can anyone please tell me a way to prevent objects receiving shadows in Poser 8?

I don't know how to do it in Poser, but you might be able to cheat. Render two versions of the scene. One version with everything except the item you don't want shadows for, and another version with only the item you don't want shadows for. Save them in a format that supports an alpha channel, like PNG, then compose the two parts as layers in a paint application.

i made a mistake in my post. i meant Poser not photoshop

Thnks ice boy, but I don't use Python scripting. And anyway, I don't ant it not to to receive ray traced light - just not shadows.

Quote - i made a mistake in my post. i meant Poser not photoshop

Quote - Provide a screencap of your scene.

http://www.renderosity.com/mod/gallery/full.php?image_id=2074789

As you can see, I've fudged the background by turning the alt diffuse colour to dark grey, but I would prefer a solution that takes the lighting from the lights.

Quote - And anyway, I don't ant it not to to receive ray traced light - just not shadows.

 

That's funny, as a shadow just means that there is less light because something else blocks the light and casts the shadow... So if the object does not receive a shadow, the shadow casting object must not be present or set to not cast shadows...
So you'll need to render twice, once without the shadow casting object and once with the shadow casting object and then combine both renders...

Quote - > Quote - And anyway, I don't ant it not to to receive ray traced light - just not shadows.

 

That's funny, as a shadow just means that there is less light because something else blocks the light and casts the shadow... So if the object does not receive a shadow, the shadow casting object must not be present or set to not cast shadows...
So you'll need to render twice, once without the shadow casting object and once with the shadow casting object and then combine both renders...

Which was exactly what I was trying to avoid as there are dozens of shadow casting objects, and I was also trying to avoid post compositing.

But thanks anyway.

You have Poser 8 and dependent parameters.

Connect the image to Ambient_Color. Make the Ambient_Value depend on your main light intensity. Done.

could we also use depended parameters to tell poser what light to use on specific objects?

Quote - You have Poser 8 and dependent parameters.

Connect the image to Ambient_Color. Make the Ambient_Value depend on your main light intensity. Done.

Not really done. This is another fudge, rather than an accurate solution. If I didn't care about the shadows, the backdrop would pick up all of the light colour emitted by lights in the scene, and would respond to the distance and angle from the source. Using your solution, I simply guess at the average ambient light across the entire surface and set that. It's not optically accurate.

But thanks for the suggestion. The whole point of this exercise was to get the actual light casting onto the background, but not shaows.

It occurs to me now, that the simplest way to do that, is simply to turn shadows off across the entuire scene in Poser's render settings - render that, then turn them on, and composite in Photoshop. Not ideal because I was hoping for a single rende solution, but more accurate than the other options,although I stil like the alternate diffuse channel solution a lot.

Thanks all.

Quote - You have Poser 8 and dependent parameters.

Connect the image to Ambient_Color. Make the Ambient_Value depend on your main light intensity. Done.

 

I don't get this. How do I set this up?
I have no access to parameter dependency in the material room and no access to the material room values in the dependent parameter window.
If there is a way too get a material room value node to appear as a dial in the parameter window, I think I could get it to work. I have seen this so I know it can be done, but have no clue how to do this.

Any links or guidance would be appreciated.

Wim - in the mat room, on a parameter, click the key to make it animated. A parameter dial for it appears in the parameters window.

Thanks BagginsBill!
I never knew that. This creates a new set of possibities: controlling more than just the pre-existing dials

How would this work?

Render your cyclorama background. Save that render and then load it as a background image. Load the other items as before (but not the cyclorama this time). In your render settings, make sure that  'render over background' is enabled and render the picture. The objects in the scene should cast shadows (which should be caught on the ground plane as that is set up by default to be shadow catch only) but wont cast shadows onto the cyclorama background image. If necessary, increase the size of the ground plane to cover all of the area that your scene items are on.

if only we could in P8 or PP2010 have  options  what lights to use on figures and objects.

this would really be groundbreaking. why cant SM just leave the code open so that someone would writte a script?

Because scripts involved in the actual rendering or ray tracing process would be uselessly slow.

The ability to qualify which polygons react to which lights, and which shadows, is actually a non-trivial change to the renderer, given how it is built. (This info I got from stewer.)

Far more possible would be material room changes that offer variations of the lighting nodes with more options. For example, a Diffuse node that has a specific list of lights it consults, and whether or not to pay attention to shadows would take care of it.

i just hope that we have the chance to use DM shadows for transmapped hair and dynamic hair.

i can not use high poly transmapped hair with raytraced shadows.

Raven, thanks for your suggestion but this solution won't work I don't think.

Imagine, I render a background using the scene lights (say 50% brightness) and save as an image, which I then load as a background. When I now put all the other objects back in the scene and re-render, the background's 50% again reacts to th 50% lighting, giving me 25% brightness in the background.

Quote - How would this work?

Render your cyclorama background. Save that render and then load it as a background image. Load the other items as before (but not the cyclorama this time). In your render settings, make sure that  'render over background' is enabled and render the picture. The objects in the scene should cast shadows (which should be caught on the ground plane as that is set up by default to be shadow catch only) but wont cast shadows onto the cyclorama background image. If necessary, increase the size of the ground plane to cover all of the area that your scene items are on.

I think the point was to "bake" the 50% light into the backdrop using a shader that responds to lights. Then - load the saved render into a one-sided or as the Poser background, and set it up so that it is self-lit, i.e. just plug the rendered background into white Alternate_Diffuse or plug into white Ambient_Color and set Ambient_Value = 0, and turn off the lighting stuff (Diffuse_Value = 0, Specular_Value = 0).

Here's what I meant. In this render (1), you can see the shadow going up the cyclorama. Not what you wanted I believe. So I just rendered the cyclorama and exported the image. In the material room, I applied the saved render to BG Picture node of the Background (2). In my render settings I choose render over Background Picture (3). Lastly shows the final render with a shadow appearing on the floor (4). The only thing in the final scene is the mannequin and the ground plane. As you can see, the background picture is the same colour in the first and last render (It may not look it as presented, but when layered in PS and turning the layer off and on, the only difference is the figure).

Ahh, thanks guys - that's worth exploring. Thank you.