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xeltestic
04-27-2010, 07:11 AM
Hi,

There is a lot of information on linear workflow and I have tried to make my self knowledgeable on the issue. Now working first time with float I was hoping to get an answer to a question.

So what would be the next step after tonemapping with 32bit float in AE. Many effects aso work only in 16bit float and the final output is going to be in 8bit. So do I continue to work in AE inside the same project and adding these effects after I have finished my tonemapping. Or do I need to render my project out as a 16bit float and continue to work in a new project set to 16bit float? Or how is this done in general?

Thx for your answer. Best regards.

xeltestic
05-05-2010, 09:35 PM
...just as a follow up. i did continue to work in the same project set to 32-bit and using 16-bit filters after doing my tone mapping. At least to me there wasn't any problem with that approach. Still time to correct me be4 getting bad habits :)

Swahn
05-06-2010, 07:58 AM
If you seek linear workflow in AE you should also set the Blend Colors Using 1,0 Gamma option http://img708.imageshack.us/img708/2140/61587272.png.

The downside to this is that alpha levels seem to be affected as well. Instead of linear gamma you get 2,2 gamma. While layer colours will blend correctly (which is important if you are working with float material) the alpha levels will look wrong because of this.

http://img404.imageshack.us/img404/6179/48013645.png
Wrong alpha (2,2 gamma?)

You have to correct the alpha levels on each layer like this
http://img175.imageshack.us/img175/8621/74728698.png

To get correct alpha again.
http://img402.imageshack.us/img402/4871/14211161.png

I think the 1.0 Gamma option also affects the alpha, from linear to 2,2, which i think is just wrong. As you mentioned most tools will stop working with 32bit channels, even with 16bit you loose some tools. I always felt that Adobe's products where built for low dynamic range imagery, and that float features where added much much later in a rush. To work linear in float is just a pain in After Effects, but also in Photoshop too unfortunately.

Although tools like Nuke and Fusion are much more pricey than the whole CS-suit they provide real support for this workflow, from the ground up. But if you also have any of the latest 3ds max or Maya versions you also have their own compositor (previously known as Toxik) wich comes bundled for free with the tools. It's actually quite good for compositing and linear workflow, much control over colours ect.

xeltestic
05-07-2010, 07:50 AM
Hi Swahn,

Thank you so much for your detailed answer. Come to think of it I did run into alpha issues which I didn't know how to tackle. With your advice at hand I will take a look if I can work around it. I have read about the limited capabilities of Float in AE compared to Nuke and Fusion. Im still trying to get my head around on all the advantages linear workflow will have. So far I like what it does and it helps me extract a lot of information otherwise lost. Unfortunately at this time I don't have access to neither the newest version of Maya nor Max though I have heard about their new compositor feature and I am very excited to say the least. Well, I must try it one day to be able to make my own opinion.

best regards

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05-07-2010, 07:50 AM
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