I shot the sheriff!
richard.chaos_91798ec102
Posts: 0
Okay I am having no luck at puling this off! The Background is a pic I took myself. I have a Shadow catchers object and a dome light and 4 other spot lights working on this..
I am having no luck with a dark shadow under the car... No luck with any definition of the car body at all.
In real life even if one has a solid black shiny car you can still make out the details!!!
Also the license plate is like glowing screamingly loud
UPGUNNED.jpg
600 x 443 - 230K
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Comments
What are you rendering in?
Kill the Ambient on the plates...
What kind of shadow?
Any custom/special shader for the carpaint?
Is there an reflection set for the paint?
What are you rendering in?
Kill the Ambient on the plates...
What kind of shadow?
Any custom/special shader for the carpaint?
Is there an reflection set for the paint?
Yes car body is a texture map for color, some shine and highlight. Reflection set at like 6 percent. I am not sure what ambient on the plates is or how to shut it off? All shadows have a soft shadow to some degree!
Rendering in Carrara 8 pro
What's the "to some degree" for soft shadows? Are you using soft shadows for the light dome lights? The point of a light dome is to provide light from multiple directions, simulating Skylight or Indirect Light. They should create their own soft shadows depending on the number of lights. Light domes and HDRIs (using Skylight) as mentioned should produce diffuse shadows. To create the darker shadows and highlights you need to use something bright such as a spotlight or distant light. If you use soft shadows, the larger the light diameter, the fuzzier and more diffuse the shadow's edges. If you couple that with a shadow setting of less than one hundred percent it could look like you have no shadows at all.
Do you actually have anything for the reflection on your car to reflect? Backdrops don't add reflections. To turn down the "ambient" mjc1016 refers to (maybe a DAZ Studio term?) I am assuming it's the Highlight/Shininess. Speaking of Highlight and Shininess, try turning the Highlight up (brightening) using a 1-100 slider and the Shininess down ("spreads" the Highlight effect) using the 1-100 slider.
It may be best to simplify your light set up first. Hide or turn off all lights except the main light (sunlight) which is shining on your car. Might work best to make this a distant light. Look at the shadows in your photo to see how they spread. Turn on Soft shadows and try increasing the light diameter from the default .08 ft to 25' Increase in increments of 25' until you get the desired spread. The shadow will appear very dark. Now is the time to try your light dome. If it washes out the shadows adjust the brightness of the lights down.
I play in Carrara rarely, so I tend to stick with Studio terms (haven't actually done anything in over a year)...
Another thing...with black car paint, in general, it's not usually completely black. In RGB terms, it could be something like 1 1 1 up to about 7 7 7 (extremely dark grey) or even something like 0 0 3 (very, very dark blue) as a base with tiny metallic particles in it or particles of a lighter colored pigment. And some type of glossy top coat. All arranged in layers...sometimes with differing refractive and reflective properties for the layers.
It's those particles and differences, especially along edges, that keep the details from getting lost.
So a shader for it should be a little more complex than just a texture map.
Adding something that can actually be reflected will help some. Almost every renderer around needs either actual geometry/environment or some kind of 'fake' (environment map)...something to reflect...to be surrounding the item you want to be reflective.
one idea
try sticking the background pic in one channel of the car textures - eg the reflection channel or if that doesn't work even tghe glow channel -combined with an operator so you can change the degree
for the blender you could try 0-1000 percent if in the reflection channel or maybe the highlight/shinyness channel (can't recall the appropriate one)
I assume you put the image into the backdrop of the scene in Carrara, or maybe composited it externally in **shop or something. You can ALSO put it in the background of the scene in Carrara, which is used for reflections. For more accurate reflections, the ideal would be a spherical image in the background slot. (keeping your existing image in the backdrop slot.)
For that spherical image, you have a few options, such as Hugin to stitch multiple photos into a panorama, or use a single photo of a mirrored ball, and use a program such as HDRShop (The free version 1, not version 2.) or Flexify to convert that to a latitude/longitude map. Ideally you should take that photo or pano sequence from the position of the car, as that will give the best reflections. (Assuming you still have access to the location.) It may sound like an HDRI technique, and partly it is, but if you are doing the lighting manually, there is no need for multiple exposures or real HDR.
The mirrored ball is a trick used by movie studios to capture an environment map for mixing CGI with live action. This will work: http://www.mcmaster.com/#alloy-steel-balls/=lva6yk
or something like this: http://www.ebay.com/itm/STAINLESS-STEEL-MIRROR-POLISHED-HOLLOW-SPHERE-1-PC-6-DIA-15299-66-/400435684438?pt=LH_DefaultDomain_0&hash=item5d3bd3a456
The 2" version is easy to carry with your camera equipment, and I made a small holder to fit mine on a tripod. The larger one will give you more detail.
Also, for your shadow, make sure the ground is set with the shadow catcher shader, and make sure you have a good strong light source (wherever the sun is supposed to be) and the other fill lights are toned down. If the sun is at 100%, and you have 5 other fill lights, they should be set less than 5% each, at least to start with. (Adjust as needed from there.) That should help with the bright license plate. With that black color, and nothing to reflect, it would be easy to over-do the lighting. Adding a simple grey ball to the scene will help you adjust the lights. The sun should have soft shadow, but not too soft.
You might also bring that black up a little. No paint I've seen is truly 0% black. Try 2% or 4% and see if that helps. You don't have to change the texture. Just use the "Add" operator in your shader to add the 2% to the texture. (Multiply can also be used to adjust overall brightness) And once you add the background, make sure there is some reflection, maybe in the 10% to 20% range.
Attached: Sample I did in Blender using similar techniques. I probably should have increased the reflection some more.
http://www.youtube.com/watch?v=AO_VgqORdVQ
Also try backing off on the dome lights, and focus more on the lights providing the directional shadows you're looking for. Once you get your shadows happy, perhaps you can bring you dome lights up a touch again.
If you don't want to mess with a spherical render for reflections, and you planned ahead and got a couple different angles when you snapped the original photo, you could add a plane to the scene, apply one of your other images to it and place it behind the camera. It will need to be large enough that the whole plane is reflected in the car. You could pre-blur the photo so you get blurry reflections as well. Might help to put the phot in the glow channel and adjust intensity as needed.
I got a catch 22 ! I just by chance turned on the GAMMA CORRECTION in the render room and finally got my reflections I wanted to a point! SEE PIC! BUT when the GAMMA is set it washes out the Background IMAGE! ANY clues?
One option is render out the alpha layer, and then composite the background with an external program. (Don't forget to get a shadow layer, too.)
Or just turn up the reflections and the black level in your shader.
So did you try any of the suggestions by any of the responders to your post? I gotta be honest, none of the images you posted actually looks as if the car is part of the photograph. Disable any GI (if any), play with the lights and shadow settings then test render with GI (if any) to see if it gets the results you want. The main thing is to start with one light at a time.
Another tip you could try is to enable the alpha channel in the Render room and render the car out and composite in Photoshop, Gimp or whatever. You can even leave the Scene Backdrop image and Background images in place as long as you don't use pre-multiplied alpha. Just make sure you render to an image format that supports alphas, such as tiff, Photoshop or .png.
If you take the time to read and try the suggestions, it can be done. Take this example, I did it for one of my nephews.
The first image is the composite. The second is the backdrop photo and the third layer is a reflection pass. The one with the masked out Duck is what the reflection pass looks like straight up. The Shadow Catcher doesn't catch reflections so I had to cut the puddles out in Photoshop and add my reflection pass. I placed a reflective shader on the plane I had initially set up as the shadow catcher, placed a plane above it with a picture of the sky I had the forethought to take and rendered. I used blurry reflections. I did this, so I could get the reflection of the Duck, otherwise it would have been more efficient to just stick the sky picture on the ground plane.
A few more. I use no form of GI whatsoever. Start simple with the primary light and then study the photo to see where else you may need reflected light.
Gee Evil, those kids feeding spike look real :)
Hah! Fooled ya'! It's Spike that's real!
Those are some awesome composites, Evil!
Professor Chaos,
I really like that car of yours! ;)