Backgrounds through Conservatory Glass

masterharper64

Can anybody help? I am trying to render an image using The Conservatory from Daz3D and ARTCollab. However, no matter what I do, I cannot get the backdrop image to render through the windows. I have tried reducing the opacity of the windows to 0%, changing the ambient colour, etc.,etc., but being new to 3D creativity, I have now exhausted my massively limited knowledge........

Chohole

You coould try putting your backdrop image onto a plane, as a texture

FirstBastion

Which application are you rendering with?

Richard Haseltine

What are your render settings? If you have refraction or reflection in the glass and ray trace depth is too low (2 should be OK) then the render might stop before getting to the background. How are you saving? If you are using a backdrop image and are saving as PNG or Tiff you may be losing the backdrop to the alpha channel.

masterharper64

Thanks for the replies,folks.....

@chohole, I'm still very much a novice at this and am not sure how to do that.

@firstbastion - I'm using 3Delight which came with Daz software.

@richard haseltine - I'm saving as jpeg. Will have a look at the render settings as per your suggestion....

Steven-V

Putting the image onto a plane as a texture:

Create -> New Primitive and select "plane".

Then click it and under "Parameters" resize it in X and Y to be the same proportions as your image. For instance, if your image is 400 x 600, make the plane 4x6 units.

Then using the Wardrobes and Props menu, use the Surface Selection Tool (in the default UI, I think it's at the top of the preview window, second button over from the left). Click the surface of the plane. Then choose the "Surfaces (color)" menu. Under Diffuse, set the color to "white". Then click the little down arrow next to the color and choose "browse". Browse folders to your image and select it, and say "OK." This should bring the image onto your plane. Then rotate the plane to put it behind the conservatory.

Now to your larger point, in terms of background images. I do a LOT of work with this, since I am making a comic book, and I have characters flying through sky or zooming over farmland or whatever, and there is just not a good way to create these things in 3D without a lot of work and effort. So I need background images. Here are some things to think about.

If you are going to use the background image feature (which I have stopped using entirely, to be honest), make sure your render window is the same proportion (and ideally, same resolution) as your image. Thus, if you have a 1024x768 image, then you should render a 1024x768 picture. If you do something on a different ratio, say square, you are going to get a squeezed or distorted background image. So either re-size your render window or crop/resize your picture. You can get away with the proportions being the same but the rez being different, but even that is honestly not ideal.

If you are going to use a plane object, beware the lighting. If you use spotlights you can get shadows of your buildings or characters onto the backdrop, which is probably not going to look right. If you don't illuminate the backdrop right, it will look over or under exposed. Using the background image feature avoids this but, again, has its own issues.

Another thing to consider is that frequently it can help to have components of your shot rendered separately and then composited in using software like GIMP or Photoshop. For example, when I am shooting a night fight, I want the characters to show up but the background to be dark. Trying to light them in the same scene is really difficult -- either the characters are hard to see or the background looks to bright for night time. So what I have taken to doing is setting the scene up once, and then render the characters on a blank background first in bright light, and then dimming the light and shooting the BG without the characters. Then I use PS to layer them in together and it looks pretty good (not perfect, but good enough when shrunk down to the panel size of a digital comic). If you render your background WITH the characters, you cannot do this, so just be careful with it.

Honestly, my preference when doing something like this, even with windows or glass, is to render against a blank background using a .png output rather than JPG, which gives a transparent background. Then I will use PS to paste in a nice sky or other background from a place like CGTextures. Usually if the glass is present, you will see the effect through the glass even this way, if you layer the background UNDER the glass layer.

EDIT: I have attached an example. The shot through the window is just a picture of a fire house I got off of Google Images (using the "non-commercial re-use with modification button), and you can see it is not at full brightness because there is a non-transparent window in the way.

FirstBastion

Loaded into DS4.6 and using a physical skydome, the glass worked as expected, but while placing an image of the sky as a backdrop in DS, the glass showed up white, then tried to adjust settings for both reflection and refraction the sky backdrop was visible through the glass if refraction strength was lowered to 0 or the refraction index was increased above 1.3 or so but it distorts the backdrop image. Using a physical skydome or picture plane are both viable solutions.

AndyS

Yes,

somehow that behaviour is strange.
But on the other hand:
What distance for refraction should the render engine estimate between your glass plane and the backdrop image?

So a normal window causes no remarkable refraction I found two working possibilities.
1. Set refaction strength to 0 or
2. Set the refraction color to black.

Both worked to get the backdrop image visible through the glass plane.

Andy