C4D: render shadow with alpha
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- CyBrainX
I've tried about 8 tutorials that tell me that you can use a compositing tag to hide an object that receives shadows. Hypothetically, you would make "seen by camera" unchecked, enable an Object Buffer and make sure that Object Number's buffer shows under Multi-pass in the Render Settings.
However, this does not happen at all. You either get shadows on everything but the shadow-receiving object or ignore the tag and you can get a PSD layer with the shadow but with no alpha information.
This is the result with shadow.
What would be the best workaround? It's really a shame that C4D is lacking such a commonly needed feature.
- jamesomega0
enable multipass render and add the layers you want to add for e.g. shadow, color, etc
In the save tab on the "render setting" you have to enable alpha channel. After that you'll see the the "straight(unmultiply alpha)" setting will be available in the multi-pass tab.
At least, that's what i read on the internet.
- Yeah. I read that, tried that, didn't work. Lousy internet.CyBrainX
- jamesomega0
There's also the Shadowcatcher plugin method as well:
- DoTheMacarena0
If it's a still, shadowcatcher would be fine, it's incredibly slow to render tho, so for animation it hurts.
Overlay the shadow pass on "multiply" mode, or use the pass as a matte for a color grade/adjustment layer. Use the object alpha as a holdout if there's shadow on top of your object (or place below, of course). Either way should work out with your existing shadow pass.
- CyBrainX0
I've read some bad things about the Shadowcatcher plugin. Some channels showing up for no reason, slow, etc.
- Horp0
I've also read some bad things about Shadowcatcher, like this one time, there was this family having a picnic, and the dad went off to get some petrol and supplies, and when he got back all that was left was the blanket and a sammidge.
- orrinward0
I've never used Shadowcatcher plugin, but it's really easy to just use a compositing tag.
http://www.maxoncomputer.com/tut…
I used that tutorial a few years ago and it worked pretty well with animation as well.
- orrinward0
Very very old video of mine from Uni, but this was made using exactly the method from the tutorial I'm posting.
- Only the test and very basic booleans are modeled, with lighting.orrinward
- I looked at that one before, but it doesn't give me a transparent shadow.CyBrainX
- I'd have a look at your render settings, and make sure it outputs transparency.orrinward
- What format are you saving to?orrinward
- hopefully something that supports an alpha channel.jamesomega
- CyBrainX0
Here are my render settings.
I'm looking into rendering all the separate lights under the Multi-pass render settings. I'm using the main light's shadow layer to hack together an alpha for the shadows. I think that's about as close as I'm going to get to a real solution for this.
- Rendering to PSD with alpha, channels, object buffer, separate lights.CyBrainX
- Chief0
does setting the shadow pass to multiply in your composite not give you what you want?
- or couldn't you just use it as a luma matte on itself?Chief
- nobody listens to us.DoTheMacarena
- Chief, yes, it passes to Mulitply but I still need the alpha. I need it as a static, not for AE.CyBrainX
- Hombre_Lobo0
Honestly mate everywhere says use the compositing tag, but it's complete fucking bs!!
You NEED the shadow Catcher plugin. It's the shizzle fir rendering shadows but not the the plane onto which the shadow is cast.
I have a bookmark on my pc with the download and tutorial, but I'm on my phone atm so will post it next time on my pc.
Also my gf thinks the mascara pictured is mabeline, due to it's unique coloring, is this so?? Urgent answer required!!
- I believe you. I'll look into it. For now, I hacked together some Photoshop alphas to get what I needed.CyBrainX
- nolovelost0
global illumination or just 'buy' the grey gorilla light kit http://greyscalegorilla.com/ligh…
- Lol! Misread!!
The light kit is excellent though. Prebuilt studios and soft boxes ftw!Hombre_Lobo
- Lol! Misread!!
- nolovelost0
Read the question wrong, hide the the floor, and render the alpha
- get the light kit though, render results will improve alot.nolovelost
- CyBrainX0
@Hombre_Lobo:
The gf is correct. Maybelline is doing a 40th anniversary campaign for Great Lashes. The model is part of an idea I'm going to pitch for it.
- Chief0
Render from Cinema. Open in AE. Luma matte the shadow pass. Save out as a PNG, TIFF, whatever with alpha. I guess that could be a roundabout way of doing it.
- DoTheMacarena0
I don't see why you couldn't use an inverted version of the shadow pass as a mask on itself also.
- That's what I did. I just expected a less roundabout way of getting what I wanted.CyBrainX
- pepe0
cant you just add an object buffer to the geometry and use the base layer multiplied as your shadow pass? even if it has the eyeliner in it it will be covered by your object buffer pass/
- doesnotexist0
take a picture