Sintel, the Durian Open Movie Project » Blog Archive » Sintel: The 4K Experience

    

Sintel: The 4K Experience

on December 10th, 2010, by Pablo Vazquez

Looks awesome!, but..

4K is not a bed of roses, everything is (obviously) bigger and heavier to handle, previz, space on disk, moving files on the server, and so on. Blender suffers this internally as well.

Rendering

On the render side (not compositing), the Blender internal did great, you’d expect twice the render time, but some shots did much less than that, I didn’t feel much difference locally, neither our farm did (bunch of quad i7 and some Xeon Octacores), but compositing is another story…

Compositing

The biggest bottlenecks when rendering in Blender are in the compositor, even in 2K, in some cases calculating the Defocus node takes up to 50% of the render time, if you combine that with FSA (Full Sample Antialias, calculates compositing for each one of the samples, so if your OSA/FSA is in 8, it will do it 8 times..), it can go up to 80 or even 90% of the total render time. Ridiculous :(

Possible solution? OpenCL! Tiled Compositing!, all the Blenderheads around the globe need you!, where do I have to donate?

Previsualization

Guess what we used for previz? Blender 2.49′s animation player! :)
On my computer I even have set the ‘jpg’ and ‘png’ files to open with “blender -a” (where the 2.49b Blender binary is plus the ‘-a’ tag), so just opening one image from the sequence will load it.
But this player doesn’t scale down, so for that Blender 2.5 Video Sequencer was used. Since it frees memory nicely, not the case of the Image editor..

Some Needed Fixes

- Shadow Buffers!
- – Increase them, is veeery noticeable otherwise :/ takes a while, but is worth it.

- Nodes!
- – Some nodes were having issues on high resolutions, like FastGaussian’s Blur, it have been fixed in both Render Branch and Trunk, also the Defocus node wasn’t working properly on high res, didn’t scale well..

- Exploding Pixels!
- – Couldn’t really find out why, but has been fixed, some pixesl were extremely bright and when passed by nodes like glare, would explode in a nice rainbow effect, sadly not what the director was looking for :P

- More super bright pixels
- – This ultrabright pixels (with float values of more than 10x!) sometimes need to be pulled down, otherwise they go over the range of colors and end up being a blueish spot in your render, there are many ways to do this but when you’re in a hurry the best thing is to just clamp them, so they are inside 0 and 1.0 again.
You can get this job done by using a “Separate RGBA” node, pass each channel (except alpha of course) through a “Map Value” node (enable Max and Min), then combine again with the “Combine RGBA”. This clamps the rgb values and they’re back to normal.

- Desert Shot
- – Missing lensflare and smoke sim :/

- Vignettes
- – Most of us used vignettes in the movie (dark corners and sometimes color correction), there are many ways to achieve this, some used a 4k image scaled down, some a 1k image scaled up, in my case I used an image at the beginning but switched to a Blend texture, since it scales automagically to the render-size, so is always right, and reliable.
But the images didn’t scale well before, had to be done manually and was a bit annoying, so I asked Diego Borghetti (bdiego) for a feature on the Scale node to scale whatever input to render-size, it worked out of the box and made its way to Render Branch and Trunk! thanks Diego :D

- Workarounds..
- – There are many workarounds for bugs or non-bugs but weird behavior on some features, most of them are already reported and fixed but some old files in Sintel had this extra stuff that was messing with the final result, so these needed fixing..
One that is left is for example some times when you pass an image texture node through the Scale node, it outputs black.. no image, just black, so you need to convert this image first by passing it through a colorramp first.

Changes?

Not really :( I got tempted and fixed some alpha issues here and there, and the floating collar dilemma on Proog’s shot :P (turns out the Ishtarian girl had her neck-thingie controlled by a constraint, and its influence set to 0.5!, just moving it up to 1.0 fixed the issue) but that’s all, the movie will be same as 2k, perhaps if we scale this version down we get better AA, but still, same classic Sintel you saw months ago online :)

OK I *really* have to go to the airport now, catching a plane back home! :D
I never thought I would get involved in Durian, now Sintel, it was an amazing project and extremely fruitful experience.

Thanks to the community for making this an even more awesome Open Project, without your support and cheering all the time this kind of projects wouldn’t be close as fun as they are.

Gracias!

(now you know how to thank in Spanish!)

Pablo, venomgfx, the Pinkifier as they called me on the team ♥ :)

27 Responses to “Sintel: The 4K Experience”

  1. Colin Levy Says:

    Woo! Great work, Pablo — and nice breakdown of the challenges. Have a safe trip back home!

  2. Riboshom Says:

    Yeah, some fixes wouldn’t be a luxury.
    And I still miss the preview render window in Blender 2.5.
    Let’s fix those regression before 2.6, Blender is already stable enough.

  3. DingTo Says:

    Thanks for all the work Pablo, I am sure we all appreciate all the work you and the team have put into Sintel! Have a save flight home!

    Thomas

  4. D Says:

    Thanks Pablo! You’re awesome!!! :D

  5. jayraj Says:

    Gracias Pablo and the whole durian team and the community for your efforts.
    Have a safe flight home. :)

  6. Pinpon Says:

    “you’d expect twice the render time, but some shots did much less than that”
    Really nice to hear that. I was expecting 4 times the render time :)
    (4K is actually 4 times bigger than 2K ;)

  7. Deevad Says:

    Congratz for the 4K version ;) !

  8. J. Says:

    Great, can’t wait to see the 4K version! (please make a DCP of it, more and more cinemas are getting 4K projectors)

    And goodbye, Pablo, you’re a nice guy, I hope we’ll meet again!

    P.S. Does the 4K desert shot look different from the 2K version because of the flare/smoke issue? You didn’t tell whether you solved it somehow.

    On to the stereoscopic version!

  9. Jeroen Bakker Says:

    Hi Pablo,

    thanks (and also to all the others) for your great work. It helped me to understand how a production is created and hopefully that will be brought back to Blender itself.

    It is getting clear that it is time for a compositor redesign! Even with this blog-entry you nailed some things (FSA) I was not aware of!

    Thanks for the great movie and opportunity to watch it evolve.

    Jeroen Bakker

  10. ROUBAL Says:

    Great work !

    The only visual effect that I noticed that could be missing in Sintel was the breath vapor in the snow shots, espescially when Sintel is attacked by the guardian, and is lying in the snow. By this cold weather, I thought that some vapor should be visible when she exhales. Any chance to see this in the 4K version ?

  11. Gallaecio Says:

    Actually, it would be “¡Gracias!”, not “Gracias!” :P

  12. David Says:

    AHA ! Now I know what was floating under Proog’s arm ! I couldn’t find out …
    thanks :)

  13. francoisgfx Says:

    made my vfx list & Matt added some great points in comments

    http://www.francois-tarlier.com/blog/blender-vfx-wish-list-features

    F.

  14. Jacob Valenta Says:

    2 quick questions, what was used to get the fog effect in opening shot?

    and 2, are the files up for download yet?

  15. Milad Thaha Says:

    Have a safe trip back home Pablo! You did a super fantastic job on the whole project :D ~hugs~

  16. joeri Says:

    Hi Pablo, I’m sure you are a lazy guy now.
    Letting us believe these where the only problems? :P

    Have a save trip home, and come back soon!

  17. Larry Says:

    Excelente 4K, Espero que salga la versión en 3D.
    Gracias.

  18. Mr Mowgli Says:

    I agree with Roubal! Breath vapor would make that shot waaaay more believable!

  19. Rave Says:

    Will you release models and textures? I especially want dragon model, because on the internet there are either bad looking or very expensive dragon models and I like Sintel’s one. And so far all Blender Movie projects released models and all resources. I wonder if this will be also with Sintel

  20. joeri Says:

    Rave Says: Will you release models and textures?

    It’s on the dvd set. maybe somebody will put it online.
    But if you can afford it it’s worth while to buy the dvd’s, doing so supports the next project and general blender development.

  21. Rave Says:

    Yeah, I would do it, but I am from very poor Polish city and barely have money for food and bills. My computer also isn’t good – it’s pentium 4 HT with 512 MB RAM (it uses old SdrAM modules, so can’t afford more memory) and I have Geforce 5xxx (don’t remember exact model designation), so I really can’t buy it (although I would, if I would win on the lottery, I’ll most certain give some money for an open-source project (not necessarily Blender)).

    So if someone can put DVD content on torrents or something like that, I’ll be grateful

  22. Rave Says:

    Ok, I found it on TPB. And when I’ll have enough money for it, I will buy real ones, because despite of sad ending movie was great.

    If they could make BGE better, that would be nice too… Because BGE and 3D Rad are closest things to The Games Factory for 3D Games, and only BGE supports other systems than Window$.

  23. povmaniaco Says:

    Thanks to you, Pablo to give us this I magnify work. It is always a pleasure to see it in action.
    Greetings and until a next Blendiberia!
    !Gracias!

  24. joeri Says:

    @Rave:
    ” It’s pentium 4 HT with 512 MB RAM ”

    Well, good luck opening the files… :=(

  25. Promis Says:

    I agree with Pablo, compositor is a bottleneck. I’m currently working on a project in Blender where I mostly use compositor and VSE. So I can say am using it for straight vfx. The calculations in compositor are slow, in my opinion. They are much slower than the rendering. I don’t know how much is complicated to make compositor use all available cpu cores, like the render does, but that would make things better for start.
    And yes, the rotobezier addon made my work a lot easier, very special thanks to the author.

    Keep growing!

  26. Marcelino Noble Says:

    Just want to say your article is as astounding. The clarity in your post is just great and i could assume you are an expert on this subject. Well with your permission allow me to grab your feed to keep updated with forthcoming post. Thanks a million and please continue the gratifying work.

  27. PDouglas Says:

    Hi from DOWNUNDER!
    recieved your Sintel X4 cd’s just in time for xmas. Thanx guys.
    Just wondering if the problem with “rig_props.py” got sorted.
    if so why cant I run the script?
    Keep Up the GREAT work…….
    Paul.

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