mental ray animation

[maxkid]

Hi guys,

 

I just installed max9 tiral version and checking out mental ray ,one question i had his how do you use mental ray with final gather on in animation ,how do you make it work ,do you have to save final gather map what is the method etc.here's is the query :

 

I have max9 scene with daylight set mr sun and mr sky with final gather on and i have animated daylight so how do i save the final gather map ,is there anyway of doing it.

 

Thanks,

 

darshan

[AJLynn]

Use a saved FG file, but not in freeze mode, and this only works for camera animation. If the sun is moving you'll need a new FG calculation per frame.

[maxkid]

Hey there,

 

Well I have animated my daylight can I

 

somehow save my fg map rendering every frame at say 320 by240 pixels

 

in max and then save this fg map calculation and apply this saved map

 

for say 900 by600 renders for animation.

 

Thanks,

 

darshan

[AJLynn]

You could, or you could just drop your FG settings. Try a few frames both ways and see what happens. (Remember to put FG in Freeze mode the second time.)

[Justin Hunt]

Is your camera moving?

 

If not, you may find that the FG wont update properly. If a FG sample exists and another new sample falls exacly over it, it will be skipped. So I dont think that Freezing the FG will work in this situation.

 

Having said that I havnt tried it

 

JHV

[maxkid]

Hi i have already put the render small size when I come tomorrow I will check ,

 

yes two thnigs are animted light and camera.... small sample scene downloaded from evermotion ,

 

In final gather box I have kept freeze mode. it is calculating every frame ( 120 ) so i will know tomorrow if i keep the read -write on it does not calculate the fg again for a different frame since my camera is animated .

 

t h a n k s

 

maxkid

[Justin Hunt]

Are you using the freeze correctly?

 

1) set the read/write on, remeaber to give it a file name/location

2) render ( optional to do every nth frame, although if there are animated objects/lights do every frame)

3) set AA sampling to 1/64,1/64 (for super fast rendering)

4) optional to set the resolution to half final size

 

once finished rendering

 

1) set read/Write AND Freeze

2) set AA to higher eg 4,16

3) set resolution to full size

4) render every frame

 

This can easily be setup to render both passes with backburner as you want waist time with an idol computer between passes

 

HTH

 

JHV

[Claudio Branch]

This can easily be setup to render both passes with backburner as you want waist time with an idol computer between passes

 

How do I do this? Don't I need the FG map to be finalized? What if I want to use a photon map with an FG map?

[maxkid]

Hi guys, here's the info

 

max9 scene rendered final gather with lights and camera animated for 120 frames it rendered in approx 4 hours on my not so fast machine.

 

here's the info :

 

1) final gather preset setting was set on high , only first frame with read write on and then unchecked read -write and only kept freeze on for all frames.

 

2) all 120 frames were rendered with freeze checked to on and unchecked read -write

 

3) now time to push for big render

 

4) if see the seq mp4 format there is jitter around thin boxes where the window ,is there any way i can get rid of them.

 

5) how do you find the render any other remarks from your side.

 

6) now what should be strategy for doing a big -hi res render if i wish to use the same fg map....

 

cheers

[Justin Hunt]

set the net render option in the render dialogue,

 

But first you must setup up backburner with the manager, server and monitor. read up the help file to do this.

 

First set all your render settings to calculate the FG

 

Submit the jop to Backburner, remeambering to initially suspend the job and give the job a new name

 

Then set the render to freeze the FG and submit the job again, also with a new name.

 

Save and close max

 

In the monitor fire off all the jobs.

 

The FG pass will render, and then the final pass.

 

Fairly simple once you have Backburner up and running.

 

To freeze the FG BOTH Read/Write AND Freeze must be on, not just freeze.

 

 

Claudio Branch- the process is the same, just remeamber to save the photon map to file

 

 

JHV

[fahtal]

Ok i`ve got a question.

 

If i have a animation the FG seems to flash. so i use fg freeze option( first render a fg read/write pass at low aa, then finalrender with read/write on en freeze on) as mention above. this seems to work wel when only the camera is moving.

 

BUT, when i try this with a animated sun and a still camera in a room. lets say the sun comes up en sets again.

 

the FG calculates frame 1 okay. but the next frames you see the direct light moving over the floor but the indirect doesn`t get brighter.

 

so i tried animate the camera a little bit so the geometry changes and the fg also changes. tis works well in de fg read/write pass(you see the indirect working right). but when i`m in the freeze pass. the indirect stays the same but now with the midday sun indirect effect.

 

Am i doing somthing wrong. do i have the fg to low so it always flashs?

I heard someone say something about fg_copy in the command line, but i have no clue.

 

i just use the fg draft settings and nothing else out of the ordinary.

 

here are the 3 test animations in one movie(1 no fg saved,2fg saved,3 cam animated+fg saved)

http://www.temper.nl/FGtest.wmv

[Justin Hunt]

render the FG over the whole animation not just the first frame. For the beaty pass the FGM will be avaeraged over the whole animation.

 

However due the the colour changes of the sun and sky the fgm may not be totally accurate. It may not be noticable though.

 

JHV

[fahtal]

Maybe i din`t explained myself ok. But i did a fg calculation over the whole animation every 10nth frame.

 

"the FG calculates frame 1 okay. but the next frames you see the direct light moving over the floor but the indirect doesn`t get brighter." this is what i see in de fg preview pass.

[Justin Hunt]

I stand corrected. Just tested it and now I see what you mean.

 

Basically what is happening is the FG samples are calculated one frame 1, if the camera does not move then for the rest of the frames the FG samples fall on existing samples (from frame1) and are skipped. So in effect its working as designed.

 

When the camera moves then FG samples are not falling on existing samples therefore are recorded to the FGM. once again working as designed

 

Therefore the only way to do a still camera/ changing time of day animation is not to save the FGM.

 

This is a good situation where a switch to incrementally update/record FG samples on a nth frame basis and then interpolate over the whole animation.

 

JHV

[fahtal]

I just did some testing myself again.

 

My conclusion was. when only the cam is animated you can safe the fg en use the freeze later.

 

when objects or lights are moving. you need to make your fg as smoothe as possible(you can test this nicely in p-shop with contrast) and then render it with no save or freeze(old style;))

 

but i don`t understand your sentence: This is a good situation where a switch to incrementally update/record FG samples on a nth frame basis and then interpolate over the whole animation.

 

does this have to do with command line rendering(fg_copy....)??

 

 

[Justin Hunt]

It is just something that I feel is needed for a future release of mental. As far as I know its not possible now.

 

Something like the FG samples are sensitive to time, ie they know that at frame 1 they are this colour/intensity and at frame n they are that colour/intensity and for the frames inbetween the colour/intensity is interpolated between the two frames.

 

The major down fall of this would be a huge FGM and problably longer rendering time. But the advantage is that the nth frame FGM methode would work with animated lights and objects.

 

JHV