Thea render channels missing?

@ggliatis @Christos

Just purchased Thea for Rhino and am trying to figure out how to get all the render channels saved in an exr. Or at least a png with an alpha channel. In the preferences tab I always set the exr options to 32bit, all of them. but they just turn white the next time I open them. I’ve also seen screen shots where other people have a channels tab which I seem to be missing. I just can’t seem to find anywhere to do this, any help would be greatly appreciated!

Below is as far as I get…



You can enable rendering channels from Thea Render settings. Render settings are available in the Thea Render tab below the devices section.

First you need to enable the desired channel before rendering in darkroom and then save your image file. So for example, if you wish to save your renders to a png file with transparency, first you need to activate the alpha channel, render your scene in darkroom and then save your image by selecting ‘PNG + Alpha’ from the save file dialog. The same applies when saving EXR files.

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Excellent, many thanks Christos! How on earth did I miss that?!

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You could also try a new free plugin for Photoshop called EXR IO.
Save an exr file with all the channels in it, and use it to import all the of them inside Photoshop.


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Thanks George, but too late for me…already purchased the proEXR plugin…doh!

It’s working well with the EXR file now.

My problem was with the menu tabs that are different between production and interactive renderer. It seems I always went looking for the render channels when i had the interactive renderer selected. Of course, they disappear completely in such a case, only to re-appear once the production renderer is selected. But now I know…

Just like images so much… Where to find the channels when production mode is selected:

The same is true for the rendering engines. I mean, e.g. Presto AO has other options to offer than Adaptive BSD. Now let’s say all options for Production, Interactive, Presto, Adaptive BSD, etc. could be seen all the time, you then would have to scroll in each of Thea’s tabs all the time. Just saying, because but now I know sounds a bit like things could be done better here. I personally think they chose the best way to integrate a full-feature piece of software like Thea into Rhino.

The other approach would be V-Ray’s way where you then have 3 windows on top of Rhino that can’t be docked: Settings, Materials and V-Ray RT. For users with 2 monitors that is perhaps better, when using 1 monitor it means you constantly have to move, close and re-open those 3 windows that are always on top of Rhino. Personally, after working with Thea for 3 months now, I think Thea’s way makes it look like it’s pretty much a part of Rhino.

I like that idea!

Yes that is the case for settings as @MarcusStrube mentions above.

Engines have different settings although some them are shared. In many cases also it doesn’t make sense to tweak settings that will not affect the selected engine. For example, render settings for caustics ( number of photons etc) play a significant role for adaptive BSD but not for Presto AO. Having a settings section open that will not affect your final render can be confusing and wastes too much space in the UI.


That’s fair enough. Looks like I’ve got some learning to do!

BTW- I like it very much so far, just going through my learning stage though, so will probably have more silly questions to come…

Thanks Guys!