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lasco
01-11-2005, 09:25 AM
Hi there,

Anyone would know some tip to allow
the rendering of very large sized images ?

I'm targeting resolution about 12000 x 6000
The scene is quite heavy, almost 2 million polys,
and few tens of Mb of images maps (not that much in fact,
compared to the size of the scene).
Other settings : One single spot light (sun),
AA enh low, radiosity background only 2x6
ray trace shadows and reflections on (very few reflections though).

I already knew that I'd have more chances to
render this on my old Mac (dual 867 Mhz - 2 Gb RAM)
but if the rendering started ok on friday evening
I saw monday morning that not even the half of the still
had been rendered… I gave up with the Mac.

I tried on the PC (Pentium 4 - 3 Ghz - 2 Gb RAM)
but got at lanching the rendering a message "image creation failed".
I must precise that what I was testing at this moment
was only on a little area (camera limited region) of
around 1000 x 1000 pixels, though it did not work.
I played with the segment memory limit of the
camera (tried to put much RAM for only one segment,
as well as very few RAM for many of them) but it did'nt
change anything either.

Eventually I decreased the res. of the still until I
did not get that ugly message.
Conclusion : the largest size LW is able to render
on my PC is 7500 x 3750

HOW can I get more ?

PS : running LW 7.5c

JML
01-11-2005, 10:45 AM
if you use a network controller, you can easily split the image adn send it on a single or different computers, and be able to render higher resolution..
(I rendered last week something like 10800*7200 with 2Gb of ram) (i used 10 nodes so it was pretty fast..)

if you have your heavy scene loaded in LW and you try to render your scene at high rez inside LW , you may run out of memory.
and it seems you did, "image creation failed" happen to me too when I have one of my project open and try to render in LW at high resolution.

it will work if you render on your own computer but with screamernet. that will work.
(even if your scene is loaded in LW)

(by the way, you probably will be able to render at 12000*6000 but it may take
a Looong time, especially if you use only 1 computer and radiosity...)

and you may want to upgrade to 7.5D

JML
01-11-2005, 10:49 AM
and even if you will be able to render with screamernet, (assuming you have a good amount of ram)
the larger resolution Lw can do is 9000*9000 I think , so to do more, you Have to
split the image.

lasco
01-11-2005, 12:52 PM
JML,
the fact is that I DID split the image,
in very small parts besides (around 1000x1000 pix).
I used Splitrender for this.

All the tests I mentionned above were made
on splited parts of the scene, except the rendering
launched on the Mac that is the only one that worked
but unfortunately too too long.

I also tested that with LWSN (got a 4 nodes network)
and it was also a failure, until I reduce the size of the
whole scene to 7500x3750.

Actually the splitting of the image did not change
anything in that case…

ingo
01-11-2005, 01:03 PM
........I already knew that I'd have more chances to
render this on my old Mac (dual 867 Mhz - 2 Gb RAM)
but if the rendering started ok on friday evening
I saw monday morning that not even the half of the still
had been rendered… I gave up with the Mac............

Well the Mac would have finished the rendering now :D As usual render the max possible resolution and scale it, or is it for an high-glossy art magazine ?

lasco
01-11-2005, 01:11 PM
Unfortunately no Ingo,
the Mac would not have finished at all.
I computed it and saw the image would only have been
finished thursday…
Sure that if I don't find any solution I'll have to save
money and buy a G5 but I'd prefer spend it to
buy some more chickens and rabbits for the farm. :)

Its an urban project I'm working on (2 km x 1 km large)
and I'd like to print at a very large scale with as many
details I can get.

ingo
01-11-2005, 01:35 PM
Well than the picture is finished on thursday, so what, its finished. I wouldn't have stopped it while looking for a better solution. Otherwise i have noticed that FPrime handles memory for big renderings better, but its anitaliasing sucks at the moment.

Otherwise render in steps. Make one complete scene and copy it several times, than render only a part of it in every scene (means delete some of your objects to get less polygones) and combine those renderings later.

JML
01-11-2005, 02:25 PM
install 7.5 D
I had the same kind of problem before, now everything is fine with 7.5D
there was some problem on how LW was handling limited region, it would
create a image buffer for the whole thing instead of just the limited region or something like that..

install 7.5 D

like I said, I recently render 10800*7200 and before I could not do that because
of the image buffer thing..

lasco
01-12-2005, 12:32 AM
the fact Ingo is that I just could not let the rendering go.
I needed the Mac for other things and had hope it
would be free after a whole week-end. Plus I unfortunately
never found and good version of Lightwave without dongle, see me ?
So if my dongle is used by the Mac for a computing that mean
I can't work on my PC…

The only thing you can do without dongle is render with LWSN.


Yep, I know I should do the second thing you suggest ;
but many, many workarounds for this…

pdrake
01-12-2005, 12:48 AM
electric image

:p

ingo
01-12-2005, 02:10 AM
Thats my usual last hope, although their raytraycer is very slow.

JML
01-12-2005, 06:42 AM
electric image

:p
no way electric image can render that amount of raytrace stuff at these resolution.

Thomas M.
01-12-2005, 08:20 AM
Hi Lasco,

just search the forum and the others for your problem. There are some ways to do this. I started a thread in the tips and tricks area about 2 month ago.

The point with SplitRender is that it doesn't help at all with the image creation failed issue. SplitRender is only for scenes Lightwave can handle by itself and therefore just makes it possible to render one image with several computers at the same time. It doesn't make your scene "smaller". The author of the plug in says so himself on his website.

Good luck
Thomas

JML
01-12-2005, 11:07 AM
if LW can render your scene at 7500x3750
then you can render 12000*6000 by spliting it with a network controller with LW 8.0.1
without any modification on your scene.
12 000*500 stripes for examples. (using limited region, not segment buffer)

it works, I did it.

JML
01-12-2005, 11:30 AM
The point with SplitRender is that it doesn't help at all with the image creation failed issue. SplitRender is only for scenes Lightwave can handle by itself and therefore just makes it possible to render one image with several computers at the same time. It doesn't make your scene "smaller". The author of the plug in says so himself on his website.
Thomas

this is truth if you get the "image creation failed" message when trying to render
small resolution images.
(and it mean your scene is really huge if it can't render your scene with 2GB of ram at low rez)

BUT if it happens when you try to render at a high resolution then it mean there is
not enough memory to render at this resolution.
if you don't get this message when you render 7500*3750 (28,125,000 pixels) then it's fine, just split the scene into stripes which are equal or smaller than this amount.
6 stripes of 12000*1000 (12,000,000) will render fine. (at least with 8.0.1)

JML
01-12-2005, 11:44 AM
just to make sure, I opened a old scene with 3.1 M polys,
I rendered with screamernet 1 stripe of 12000*1000 , and it started rendering whitout any problem.
(I also had the scene open in LW at the same time)

(computer is P4 3Ghz, 2Gb of ram,winxpSP2,etc..)