Newbie alert!

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Alexos
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Joined: Thu Oct 08, 2009 10:28 am

Newbie alert!

Post by Alexos »

That would be me. Just bought the program and - despite the seemingly excellent wiki - I'm rather clueless on how to set it up and, more importantly, why things happen. So far I've tested it with four different scenes (I thought I could use old stuff to compare it with native LW) and, well, here's my results:

- very simple exterior: K-ray rendered it in about 1/3rd of the time of Lightwave (albeit with no significant differences in the output quality, but I'm willing to believe it's entirely my fault - I just selected "high" settings and let it go);

- *extremely* complex interior with 142 surfaces, lots of imagemaps, reflections, 12 different lights that LW rendered in oh, about 18 hours I believe: K-Ray (and LW) crashed as soon as I hit "render frame".

- same as above, another room of the same apartment: same result.

- A very simple interior scene I set up a while ago just for the hell of it (alabaster columns, fog, man, 3 surfaces, one light): LW renders this in about a minute, K-Ray's preview stays black for 10+ minutes - I killed it at this point.

It's obvious I'm missing something - more than something, I guess. But what? Apart from making the model watertight, avoiding unnecessary luminous surfaces and (I suppose) lights above 100% intensity, what should I look for?

ADP.
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Janusz Biela
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Re: Newbie alert!

Post by Janusz Biela »

Alexos wrote:That would be me. Just bought the program and - despite the seemingly excellent wiki - I'm rather clueless on how to set it up and, more importantly, why things happen. So far I've tested it with four different scenes (I thought I could use old stuff to compare it with native LW) and, well, here's my results:

- very simple exterior: K-ray rendered it in about 1/3rd of the time of Lightwave (albeit with no significant differences in the output quality, but I'm willing to believe it's entirely my fault - I just selected "high" settings and let it go);

- *extremely* complex interior with 142 surfaces, lots of imagemaps, reflections, 12 different lights that LW rendered in oh, about 18 hours I believe: K-Ray (and LW) crashed as soon as I hit "render frame".

- same as above, another room of the same apartment: same result.

- A very simple interior scene I set up a while ago just for the hell of it (alabaster columns, fog, man, 3 surfaces, one light): LW renders this in about a minute, K-Ray's preview stays black for 10+ minutes - I killed it at this point.

It's obvious I'm missing something - more than something, I guess. But what? Apart from making the model watertight, avoiding unnecessary luminous surfaces and (I suppose) lights above 100% intensity, what should I look for?

ADP.
It is better when You share scene, if You can`t send me via mail janusz@render.fi (max limit 60 MB) I will check. :)
jure
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Joined: Thu Jun 02, 2005 6:53 pm

Re: Newbie alert!

Post by jure »

I guess a typical newbie mistake is to plug in any old scene that was setup for LW and expect Kray to do the miracle.

1.st: high setting is overkill most of the time. Good starting point is medium preset
2.nd: you need to setup the scene with Kray in mind which means forget fake fill lights, colored shadows, fake shaders etc. Try to setup scene as realisticaly as possible and let Kray do the light bouncing for you.
3. If scene crashes send it to us so we can check it and fix any bugs that may be there.
- Jure
Alexos
Posts: 35
Joined: Thu Oct 08, 2009 10:28 am

Re: Newbie alert!

Post by Alexos »

jure wrote:I guess a typical newbie mistake is to plug in any old scene that was setup for LW and expect Kray to do the miracle.

1.st: high setting is overkill most of the time. Good starting point is medium preset
2.nd: you need to setup the scene with Kray in mind which means forget fake fill lights, colored shadows, fake shaders etc. Try to setup scene as realisticaly as possible and let Kray do the light bouncing for you.
3. If scene crashes send it to us so we can check it and fix any bugs that may be there.
Hmm... Well I didn't quite expect miracles, but I did hope it'd work (I generally don't do fancy lighting tricks). I checked the model and it was OK, so I just stripped all surfaces and tried again: this worked. Now I can't be bothered to go back and recheck all surfaces, there's just too many of them and it's an old project anyway - and I don't think I can send you the scene and let you have "fun" bug-hunting it cos there's a lot of commercial stuff in there... too bad, but then again no big deal.

With this setup, LW renderer took about 5 minutes (on an 8-core Xeon); K-Ray took two. That's ridiculously fast, I AM rather pleased! As you can see the final image is a bit darkish, which begs the question... In this situation, what's the "K-ray correct" way? Crank up the sun light? Leave sun as it is and add fill lights? Increase recursion (it's at 48 now)? Something else I can't imagine? :)

Furthermore, as you can see, apart from the LW one being generally crispier (that's the AA, I suppose; I need to figure it out) something strange has happened to the small library at the back. What's that? Why did K-ray treat it so? I *can* send you this claylike scene if you want...

Thanks a bunch!

ADP.
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LW render
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K-ray render
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Janusz Biela
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Re: Newbie alert!

Post by Janusz Biela »

Please share model without texture and camera setup.
Alexos
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Re: Newbie alert!

Post by Alexos »

Johny_quick wrote:Please share model without texture and camera setup.
There you go. I got rid of a lot of unnecessary stuff and actually cut away 2/3rd of the apartment... but the Dark Shelf is still there. Thanks!

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erwin zwart
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Re: Newbie alert!

Post by erwin zwart »

quick load-and-render shows fine result here. Please include your LWS.
kraytestEZ1.png
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kraytestEZ1.lws
quick and dirty settings
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Alexos
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Re: Newbie alert!

Post by Alexos »

erwin zwart wrote:quick load-and-render shows fine result here. Please include your LWS.
Oh, bugger. After reading your post I double-checked the LWS and found out that the shelf layer had an overlapping clone. Removing that fixed everything... I feel rather embarrassed now. Sorry guys :oops:

On to more testing and hopefully less pointless questions...

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Janusz Biela
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Re: Newbie alert!

Post by Janusz Biela »

IMHO this model has bad conversion from CAD or another software.
Wire have many errors etc. LW CAD help a bit . But always when I use CAD models always I have problems....double surfaces, twist poly, etc...
Time render 1:50 min...and some errors in corners - NOT from Kray :lol:
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Alexos
Posts: 35
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Re: Newbie alert!

Post by Alexos »

Johny_quick wrote:IMHO this model has bad conversion from CAD or another software.
Wire have many errors etc. LW CAD help a bit . But always when I use CAD models always I have problems....double surfaces, twist poly, etc...
Yeah, it was a .3DS generated by archicad. I cleaned it up as much as I could but some things would have needed to be rebuilt... except we were on a deadline as usual. Archviz can be painful! :)

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