Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: piripi on 2014-06-22, 13:32:26

Title: "best" rendersettings for animation with shadowchatcher
Post by: piripi on 2014-06-22, 13:32:26
Hi guys,

i'm working on a short experimental animationmovie. i shoot footage with the black magic pocket camera and want to mainly use it with the Corona_shadow_catcher_material.

i made already some tests.

Not a valid vimeo URL
http://ifglitch.com/post/87723860506
http://ifglitch.com/post/87977714301

i used the standard settings, with mblur on shutterspeed 50-150:
images will be lit by HDRI (selfmade with mirrorball) if there is straight sun i'll use a corona sun additionally.
the dof i will do in post with standard ae dof blur



so now my questions are:

0. i'm using corona alpha build, version release 17.6.2014 (any recommendations? should i use older/ different build, only thing i need shadowcatcher...)
1. render engine (progressive or bucket)?
2. Sampling balance (not sure if i should change any ;)
3. HD Cache:
4. ok lets say the settings are fine and i'm ready to render.
- normally i change the pass limit so 50-150 passes depending on the hdri and the light.
unfortunately sometimes it  happened, that the rendering got stuck on one frame (corona info popped up telling something is wrong, and asked if i want to irgnore it, us pressed than on ignore all...
is there a way to prevent popping up this stuff, or just to ignore is completely
 (reading helps ;) Quote keymaster info.txt in daily dropbox)
5. renderfarm tool:
does it make problems to use a renderfarm tool like renderpal or backburner?

6. is there a tutorial out, in which is explained how to comp the passes together? (refl, refr, direct, indirect etc.) just to get the beauty pass?

7. i asekd already in the shadow catcher tutorial thread, but to have it all organized in one thread
https://forum.corona-renderer.com/index.php/topic,3995.msg29796.html#msg29796

how to get the bluish shadow back? (see attached image)? am i doing the comp wrong?

ok sorry for maybe asking  stupid/unskilled/underskilled questions.
thanks in advanced
piripi
Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: Ludvik Koutny on 2014-06-23, 09:49:30
Hi, i will take a look at solutions to those questions once i get home from  work. :)
Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: piripi on 2014-06-23, 15:25:34
cool, thnks, i'm looking forward for your solutions :)
Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: piripi on 2014-06-25, 23:41:59
anybody some recommendions? i have a deadline coming closer :(
i making right now tests pt+pt vs pt+hd.
i'll post the result tomorrow, when the rendering is finished.

i'm not really sure what the bucket stuff does? can it produce flickerless images or is it just for renderfarms like rebus for better time calculation?


p.s. i use renderpal, which seems to work really nice sofar, by the its for free up to three node, way more control than stupid backburner... ;)

thanks
piripi
Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: piripi on 2014-06-26, 18:28:05
ok lets continue talking to myself ;)

here a small render compare between pt-pt // pt-hd


the pt-pt has more noise, but does not flicker at all! to i think i will continue with pt-pt.

pt-pt 1000frames = 7h 9 min
pt-hd 1000frames = 6h 22min

in the video on ytube is hard to see, but the pt-pt has a bit more noise, which is more acceptable than this flickerstuff...

so i will continue with pt-pt as far anybody knows a trick...

would be bucket rendering an alternative? what could be "equal" settings to 25 passes?
inital samles: 5
passes: 2

what would be a good/equal value for i samples?

thanks
piripi

Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: Ludvik Koutny on 2014-06-26, 18:45:02
Sorry, been very busy.

Some quick answers.

HDcache is useful only when there's a lot of indirectly lit surfaces in your scene. That's probably not case of integrating CG objects into footages, where lighting is mostly direct. Therefore do not use HDcache, use just PT+PT. It will not be any slower in shadowcatcher scenarios. Also, HDcache flickers so it's useless for animations with moving objects ;)

There's not much reason to use bucket rendering. It won't speed up rendering in most cases. So just do not care about bucket, and use progressive. Render a frame, determine how many passes is needed to reach acceptable noise level, and then set that pass amount as pass limit.

As for compositing, you have probably your Toxik composition set wrong. Once i finally get a free time, i will post a sample composition.

To compose render elements together, just use all CESSENTIAL render elements, and combine them all together using ADD operation. Also make sure you are rendering linear output, that means leaving highlight compression at default value.
Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: piripi on 2014-06-26, 18:55:34
cool!
thanks for the good explanation!
i used this sRGB node in toxik to get the linear exrs to be "straight" maybe this is the problem... or premultiplied issue... i will test and reply.

all the best
philipp
Title: Re: "best" rendersettings for animation with shadowchatcher
Post by: Ludvik Koutny on 2014-06-26, 20:12:52
Quote from: piripi on 2014-06-26, 18:55:34
cool!
thanks for the good explanation!
i used this sRGB node in toxik to get the linear exrs to be "straight" maybe this is the problem... or premultiplied issue... i will test and reply.

all the best
philipp

The problem was that you did it wrong. HDR formats need to stay linear. What you need to do is to sRGB the framebuffer instead.... to just view it in sRGB, but keep it linear :)