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tcoursey
11-25-2014, 12:14 PM
Anyone use EXR format with additional buffers saved? I'm just trying to do some extra composite work with my 3D renders and am running into some issues. First the rendered image looks quite a bit different than a JPG or TGA when in EXR format. I'm sure this has something to do with gamma or exposure or color space. Also does After Effects see the additional buffers inside the EXR format, or will I need a plugin of sorts for that...I'm not seeing them currently. Any thoughts would be appreciated...a search on EXR in the forums turned up nothing.

Greenlaw
11-25-2014, 12:47 PM
I do this routinely between Lightwave-exrTrader and Fusion. If you're rendering in sRGB colorspace, in Fusion you'll need to add gamma 2.2 correction to .exr renders. Ideally, this is done downstream but, depending on your workflow, where you place it may be a matter of convenience. I often put it near each .exr loader because I'm usually compositing elements from various sources.

I don't really have any experience with After Effects and .exr auxiliary channels. I'd like to learn more about this though since I seem to be working in AE a lot lately. If anybody has links for tutorials, I will appreciate it much.

What I do know is that you can extract the data from AE using this plug-in: http://www.fnordware.com/OpenEXR/ The extracted data can then be piped into other plugins. I'm not 100% sure but I think this .exr plug-in comes bundled with recent releases of AE. If not, you need to download it from the website.

I can only guess how to use it because I'm actually pretty ignorant about using .exr with AE. Hopefully, somebody more knowledgeable about the AE-EXR workflow will follow up with more helpful info.

G.

Edit: Found the manual on the website. Taking a look at it later today.

Greenlaw
11-25-2014, 02:30 PM
Oh, I almost forgot. Natively, AE has a native tool called EXtractoR, which allows you to extract channels from an .exr file. I stumbled on that a couple of weeks ago. Using it reminds me a little of the Boolean tool in Fusion. Sorry that's all I've got.

If you do a search, you might find some tutorials for EXtractoR--probably not LW specific but for the process involving AE, it shouldn't matter.

G.

Edit: I think this was the tool I was thinking of when I said the above may come with AE now--that's incorrect. From what I can tell, the exr plug-in described in the previous post requires the 'pro' version, ProEXR, to extract aux channels. EXtractor, however, does come with AE. I don't know which is better though--I have no experience with either.

Lightwolf
11-26-2014, 04:24 AM
If you're rendering in sRGB colorspace, in Fusion you'll need to add gamma 2.2 correction to .exr renders. Ideally, this is done downstream but, depending on your workflow, where you place it may be a matter of convenience. I often put it near each .exr loader because I'm usually compositing elements from various sources.

For "proper" linear compositing, you'd not apply the gamma at all... until you save (and then you should use the gamut tool) - also make sure to convert other source images to linear and correct the viewers (also using gamut).
The set-up is a bit more elaborate though.

Cheers,
Mike

Greenlaw
11-26-2014, 06:30 AM
Thanks for the additional info Mike.

Yeah, I know I'm taking some short cuts. I blame volume of work I've had to push out this past year. :p

G.

Lightwolf
11-26-2014, 06:34 AM
Thanks for the additional info Mike.

Yeah, I know I'm taking some short cuts. I blame volume of work I've had to push out this past year. :p

Hah, nothing wrong with that really. I often don't bother either - if it works, it works. ;)

Cheers,
Mike

Ma3rk
11-26-2014, 10:16 AM
Edit: I think this was the tool I was thinking of when I said the above may come with AE now--that's incorrect. From what I can tell, the exr plug-in described in the previous post requires the 'pro' version, ProEXR, to extract aux channels. EXtractor, however, does come with AE. I don't know which is better though--I have no experience with either.

FWIW, when you install ProEXR for AE, a menu item is added that will create separate comps of each rendered channel contained in the EXR file imported into the Project tab. As such, you wouldn't need to use the EXtractor tool.

Greenlaw
11-26-2014, 10:32 AM
Now that's pretty cool. I'll have to check it out. Sounds like a great companion to LW w/exrTrader.

G.

tcoursey
11-26-2014, 11:33 AM
Hah, nothing wrong with that really. I often don't bother either - if it works, it works. ;)

Cheers,
Mike

Mike,
As unbias as you can be, could you tell me how exrTrader is different/better than the compositing buffer export now in LW? Interested in the investment if it does something I will want as we begin to do more post processing in compositing apps with our workflow...

Greenlaw
11-26-2014, 11:46 AM
I can tell you that it's much simpler to use. Not to knock the native Compositing Buffer system but I often feel like I have to play tricks on it to give me exactly what I need. With exrTrader, I created a few presets for what I need and it just works for me. And my comp buffer needs really aren't that complex.

That's just me though. I'm usually using Fusion for compositing so if you're using another package, your mileage may vary.

G.

tcoursey
11-26-2014, 11:49 AM
I can tell you that it's much simpler to use. Not to knock the native Compositing Buffer system but I often feel like I have to play tricks on it to give me exactly what I need. With exrTrader, I created a few presets for what I need and it just works for me. And my comp buffer needs really aren't that complex.

That's just me though. I'm usually using Fusion for compositing so if you're using another package, your mileage may vary.

G.

Thats fair enough and so far been my take as well. Seems the native isn't doing what I think it should always.... FIgured it was just me :) Now that Fusion is free we have downloaded and began looking into it. Our needs at this point are very minimal...we want to use the luminosity channel and the depth channel for sure. We are using Magic Bullet Looks in After effects right now...hope to keep that in our pipeline somehow...

Thanks for the info...

Greenlaw
11-26-2014, 11:49 AM
To be fair, it's been well over year that I last tried the native Compositing Buffer. It's possible that the system has been improved since then but I have no knowledge about that.

G.

tcoursey
12-08-2014, 08:21 AM
when you guys render out buffers do you render out Ambient Occlusion passes? It seems when I do it adds quite a bit of time to the render, I would assume that if I have GI turned on and AO checked that it would already be calculated in the regular time...what am I missing?

Lightwolf
12-09-2014, 05:40 AM
Mike,
As unbias as you can be, could you tell me how exrTrader is different/better than the compositing buffer export now in LW? Interested in the investment if it does something I will want as we begin to do more post processing in compositing apps with our workflow...
Hm, let me try to be unbiased then:
* Easier to use (at least imho):
- preview buffers via VIPER and check pixel values
- presets
- output file naming can be based on scene or camera names
- flexibility (i.e. save everything as a layered EXR, but additionally the final RGB as a JPEG sequence for playback)
* Better/deeper EXR support:
- support for limited regions saved as "data windows" (great for passes on black, if the compositor supports it)
- elaborate meta-data support
- complete control of layer/channel naming

That's just off the top of my head though. Essentially, exrTrader was designed around the EXR specs - as opposed to a more general compositing buffer export that also supports EXR.

Cheers,
Mike

Greenlaw
12-09-2014, 11:47 AM
What Mike said. If you need full .exr support, I absolutely recommend his plugin.

When I was with the Box, we had our own custom .exr saver. It did everything Mike's did plus a few extras to serve specific requirements of the department's compositing pipeline. The internal plugin worked very well for us but, even so, for pure ease of use I think I still like Mike's tool better.

When working on our Little Green Dog shorts and when I'm freelancing for other studios, I rely heavily on exrTrader. (That is, when I'm compositing in Fusion anyway. I'm still a bit lost when it comes to the exr workflow for After Effects--anybody know of any good tutorials for using exr aux channels in AE CC 2014?)

G.

Otterman
12-10-2014, 05:10 AM
I'm still a bit lost when it comes to the exr workflow for After Effects--anybody know of any good tutorials for using exr aux channels in AE CC 2014?)

G.

I second this. Even an after effects file and exr file to pick apart would be gold!

jwiede
12-10-2014, 12:34 PM
Hm, let me try to be unbiased then:
* Easier to use (at least imho):
- preview buffers via VIPER and check pixel values
- presets
- output file naming can be based on scene or camera names
- flexibility (i.e. save everything as a layered EXR, but additionally the final RGB as a JPEG sequence for playback)
* Better/deeper EXR support:
- support for limited regions saved as "data windows" (great for passes on black, if the compositor supports it)
- elaborate meta-data support
- complete control of layer/channel naming

That's just off the top of my head though.

As a long-time customer of ExrTrader, I'd like to confirm Mike's list of benefits, if anything he's downplaying them IMO. I find ExrTrader's UX/workflow substantially more efficient (esp. using presets and template names) than compositing buffer export for day-to-day usage. If you spend a little time setting up output presets, the workflow payback is manifold -- output config in most common situations (for you) turns into just selecting preset from drop-down, and that's it.

Mike doesn't really play it up, but ExrTrader historically has offered deeper/broader and more-current EXR format feature support compared to LW native EXR support -- he really does a great job of keeping up when new features are added to the format spec, quickly adding support for them into ExrTrader. I also find ExrTrader very reliable and stable to use. I honestly believe that if you care about EXR IO, you'd be doing yourself a disservice NOT getting ExrTrader. I consider it a must-have plugin, and one of the first I _always_ install.

(Again to be clear, I have no other fiduciary relationship with db&w, I'm just a very satisfied ExrTrader customer. I highly recommend ALL db&w's plugins.)

Lightwolf
12-11-2014, 09:08 AM
(Again to be clear, I have no other fiduciary relationship with db&w, I'm just a very satisfied ExrTrader customer. I highly recommend ALL db&w's plugins.)
*blush* Ahem, erm, wow... thank you very much.

Cheers,
Mike

P.S. The cheque's in the mail. ;)