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Salv8or
05-06-2010, 07:00 AM
Hi all.

Ive been looking at Kray on and of for a while, and i would like to know how well its connected to lightwave.
I've seen how the workflow is on for instance maxwell and i dont like the fact that you have to create new materials and such.

Is Kray more like Fprime in that way. How integrated is Kray? (lights, object deformation, etc.)
Are there any obviouse downsides/incompabillity issues that you know of?

Thnx in adv.

Captain Obvious
05-06-2010, 08:06 AM
Kray does not support *certain* node-based shaders. Anything that requires preprocessing is right out (such as some of the subsurface scatting). It's generally more compatible than FPrime, but suffers from the same fundamental limitations, such as no pixel or image filters.

Salv8or
05-06-2010, 08:12 AM
thnx m8.

Is there a demo/evaluation version to download from there site. Tried to register via the "download" tab, but the side never finished loading, so i could'nt.

Larry_g1s
05-06-2010, 08:16 AM
I've been using Kray for quite some time now and it's pretty well integrated in to LW. There are some Nodes that don't work well with Kray because of the way it renders. Over all it's very well integrated and a great render engine. I'll see if I can point this thread to some more experienced Kray users to see if you can get a more detailed answer. ;)

Salv8or
05-06-2010, 08:30 AM
Larry: Thnx alot.


Its probably just me, but alot of stuf that I undertake on my sparetime, gets left hanging becous I never get saatesfied with the output. I just cant get what im doing wrong. I can do som post processing and get things to look "ok". Im sure its just me beeing unable to apply gamma, exposure and all the other settings correct, but i have never been able to get a Straight out of the software interior render to be satisfying. Eather the outdoor prts will be overexposed or the interior to dark..
Thought I might take a look at kray and see if I get any further.

Jure
05-06-2010, 08:58 AM
thnx m8.

Is there a demo/evaluation version to download from there site. Tried to register via the "download" tab, but the side never finished loading, so i could'nt.

Hi,
like others have mentioned Kray is much better integrated than Maxwell or similar 3rd party renderers. It's very much like Fprime although there are couple of features not supported yet. And there are also some things supported that do not work in Fprime for example volumetrics...

For full list of features see the wiki pages here:
http://www.kraytracing.com/wiki/Features#Not_.28yet.29_supported_features

About your registration problem. Try this link (http://www.kraytracing.com/joomla/component/user/register)which should take you directly to the download page.

Demo version is in the final stages of testing so we are planing to release it next week - however I can not promise it 100%.

Hope this helps...

Salv8or
05-06-2010, 09:01 AM
Thanks a bundel friends.

Trying it as soon as I can.

Nope, still when i want to register i get this:

Message
Error
•You must enter the verification code.

But the site refuses to finish to load, so I geuss im missing the verification code submission form.

Well trying l8r on.

Thnx again.

biliousfrog
05-06-2010, 09:14 AM
Eather the outdoor prts will be overexposed or the interior to dark..


Sounds pretty normal to me, the same thing happens when taking a photograph in a room lit by the exterior environment...you either expose for the interior, the exterior or take several exposures and combine them into an HDR.

If you follow basic linear workflow (see Matt's pdf's for a primer) and adjust gamma/exposure in post you can control what is properly exposed.

Larry_g1s
05-06-2010, 09:31 AM
Hi,
like others have mentioned Kray is much better integrated than Maxwell or similar 3rd party renderers. It's very much like Fprime although there are couple of features not supported yet. And there are also some things supported that do not work in Fprime for example volumetrics...This is a big plus for Kray (and I'm a fPrime fan too). The ability to use instancing with Kray is a big bonus.

Hieron
05-06-2010, 09:36 AM
Fprime supports hypervoxel volumetrics, even in preview window. Not sure if other volumetrics were meant..

Ryste3d
05-06-2010, 12:52 PM
Kray works as a dream for us. We do Architectural work and we use Kray all the time. For interior render this is the absolutely the only way to go for speed and quality. For exterior it have nicer reflection then native LW render.

All is Kray render: www.ryste3d.com

Larry_g1s
05-06-2010, 12:59 PM
For interior render this is the absolutely the only way to go for speed and quality.I couldn't agree more on this. I'm just starting to use it for exteriors too, and with the physical sky plug-in it's very very nice.

Salv8or
05-06-2010, 01:34 PM
I still can't register on the site..
I dont know if it's explorer that dont like some script or something on the site. It's been loading for over a hour (Yes, I left the computor) but still no place to enter any verification code.

Argh!

biliousfrog: About the over/underexposure. I mean that the lighting, even if i try to expose it, becomes flat and dull or to dark/bright in the areas shadow/illuminated. And the anoying thing about it is that first you have to wait for the render, save the HDRI, load the HDRI, fiddle with the settings, just to find that you have to do it all again. I guess when you know what settings should work, you also know how the render should look before the process of adjusting it. I have no idea what to aim for and that's just eating me up.

So in conclusion, I hope that Kray will let me see the renderoutput as is, with some kind of setting that is "correct". At least I will be able to see what to adjust.

I render a close to white interior (only one surface on all stuff) diffuse around high 60% and nothing else. Just to see the radiosityfalloff, but since i dont know what to expect its hard to say what to tweek. Should i tweek the light or should i tweek the exposure. Feels a little like catch 22.

*Well now look what you just did, you just bored everyone to death with your rumbelings!*

Sorry for that, it have been on my chest for quite some time. =)

Thanks for everything.

/me, out!

Iain
05-06-2010, 01:53 PM
Not that its a biggie in this context but Maxwell actually works perfectly with LW.
It converts the materials and models automatically and you only have to create maxwell materials if you want (they are better so its worth doing).
You don't have to mess about with lights either so its actually easier to use.

I hate to say this but if you're looking for a short cut to good renders, even the best engine will only do what you can get it to do. Knowledge is the key.

Iain
05-06-2010, 01:55 PM
All is Kray render: www.ryste3d.com

Great portfolio Ryste :thumbsup:
Your use of 2d people is excellent!

Salv8or
05-06-2010, 02:10 PM
Not that its a biggie in this context but Maxwell actually works perfectly with LW.
It converts the materials and models automatically and you only have to create maxwell materials if you want (they are better so its worth doing).
You don't have to mess about with lights either so its actually easier to use.

I hate to say this but if you're looking for a short cut to good renders, even the best engine will only do what you can get it to do. Knowledge is the key.

I'm well aware of that, but at the moment it feels lika im stuck in a corner. I can make descent render, but I dont know where I go wrong. When looking at what people do, with lets say Kray, and compare it to what the same people do with lightwave native, there is a big difference.

Im sure there are alot of people that can make fantastic renders out of any renderer with a bunch of different passes and fiddeling in photoshop or AE, or someother post tool. Im not looking to spend time in a bunch of different applications, and HOPE to get what I want. When I hit that render button I would like to see what I aim for, and sure I can manage to run the result throu photoshop or what not, to retouch some final finishing, blooming and stuff. The point is that I want a near final pruduct when i test render. Not having to think: "ahh.. This COULD look good with exposure, and gamma, and bloom, and dof, and......."
Im not complaining about LW's native, I love it. However it seems to be alot of stuff to consider AND be aware off. I dont have that "awarness". I cant tell when LW delivers the result to me if its gonna be good or not. "shooting in the dark"

Gahh.. Done it again.. Loads of rambelings. *sorry*

geo_n
05-06-2010, 02:22 PM
kray will not give you instant beauty renders. no renderer would, close is vray only because there's millions of resources and presets which you can use or dissect.
If you ever buy kray start with jure's video tutorial, then read the manual. :)

Captain Obvious
05-06-2010, 02:40 PM
Not that its a biggie in this context but Maxwell actually works perfectly with LW.
It converts the materials and models automatically and you only have to create maxwell materials if you want (they are better so its worth doing).
Well, Kray actually works with procedurals and shaders. Maxwell doesn't. That makes a pretty big difference to me. :)

Salv8or
05-06-2010, 02:43 PM
Well, Kray actually works with procedurals and shaders. Maxwell doesn't. That makes a pretty big difference to me. :)
:agree:

LW's native surfacing controll are VERY important. In my opinion we have one of the best and most logical surface and shading gui. Both the classic way and nodebased.

Salv8or
05-06-2010, 04:08 PM
Hi..

I've uploaded one lw render the acctual output, as a jpg.
The image is on the wirge of beeing over exsposed in "Outdoor" area, and very dark indoors.

I have zipped and added a uncompressed HDR image, so if anyone have the time to tell me what i should do from here?
I cant make this a good image. If i try with exposure and gamma on this, all i get is washedout. so apperantly it must be done with the lighting, but what?? should I lower the "sun" or the "sky" or is it the radiosity that needs a boost?

Now this is just a quick sampel, but I think it shows what i meen.

geo_n
05-06-2010, 04:18 PM
Do you have fill lights inside the room? In real life a room with only the lightsource outside, the interior will be a little dark like that.
If you will check the interior shots in magazines, they all have photography setup to make them look nicer. Bouncing lights with those umbrella looking shields so the photographer will capture good shots. Same goes with car renders.

3dworks
05-06-2010, 04:23 PM
I'm well aware of that, but at the moment it feels lika im stuck in a corner. I can make descent render, but I dont know where I go wrong. When looking at what people do, with lets say Kray, and compare it to what the same people do with lightwave native, there is a big difference.

Im sure there are alot of people that can make fantastic renders out of any renderer with a bunch of different passes and fiddeling in photoshop or AE, or someother post tool. Im not looking to spend time in a bunch of different applications, and HOPE to get what I want. When I hit that render button I would like to see what I aim for, and sure I can manage to run the result throu photoshop or what not, to retouch some final finishing, blooming and stuff. The point is that I want a near final pruduct when i test render. Not having to think: "ahh.. This COULD look good with exposure, and gamma, and bloom, and dof, and......."
Im not complaining about LW's native, I love it. However it seems to be alot of stuff to consider AND be aware off. I dont have that "awarness". I cant tell when LW delivers the result to me if its gonna be good or not. "shooting in the dark"

Gahh.. Done it again.. Loads of rambelings. *sorry*

as i'm using both engine together with LW, i thought to write down my impressions as well...

first of all, both kray and maxwell can produce great images. the choice is maybe more about what workflow you will need or are used to. i'd say kray is more the 'engine of all trades' for LW if you need a maximum of production flexibility, as you can use procedurals, nodes, etc. combined with a lot of GI modes. also, in most of cases, it is the tool of choice if you need to do animations within a reasonable budget/ time limit. render quality can be superb, but to get that image quality be prepared for longer render times, especially because of an AA which needs rather high settings in most cases to satisfy the most critical eye. what is unsurpassed in kray is the ability to fine tune render times and the flexibility to set GI properties even at surface level. but be aware that you will have to 'fight' a bit with it to get it to be your friend, as you can get a 'feeling' for most settings only after many tests... my recommendation: study jure's tutorials even before hitting F9 ;)

maxwell, on the other side, is more focused on being a material and light simulation engine which can give you the most realistic images, without compromises, at the cost of sometimes long render times. a sort of software large format camera... the approach is as simple: if you modeled the scene correctly, used the correct materials (if you don't want to mess, simply download some online...) and set the lights as a photographer or lighter would do, you will get the expected, very realistic looking render result. the LW plugin does a nice job translating surfaces and now has a nice instancing system as well, but you'll have to dedicate a bit of time to understand how the material system is working to get the most out of it. have a look at m.verta's tutorials on the maxwell think site. imo., longer render times are compensated largely by faster setup times (no AA settings to mess with, no myriads of GI settings to fine tune performance etc) and the flexibility during rendering. for example, using intermediate render results at any time to start compositing. also, you can stop and resume a render whenever you want. last but not least, one render generates a 'multilight' image, so you can fiddle all light intensities and light colors after rendering - a great time saver.

btw, for both engines you will have to make good models, as both tend not to forgive 'sloppy' geometry. be sure your models are 'watertight', especially when rendering interiors...

ouch that was a long post :D

cheers

markus

Captain Obvious
05-06-2010, 05:46 PM
What you need to do to get nice lighting is use a linear workflow. Basically, gamma correct your output! In Lightwave, add the FPGamma 2.2 image filter, or Michael Wolf's excellent colour correcting pixel filter.

Unless you gamma correct, you will ALWAYS be fighting the renderer. It is absolutely imperative that you have at least a basic grasp on the concept of linear workflow if you want to become an even half-way decent lighting artist. Or at least a half-way efficient one — it is indeed possible to produce nice results even without a linear workflow, but it's a pain in the arse and takes much longer.

OlaHaldor
05-06-2010, 06:35 PM
I've been drooling over Kray for over a year, and just made the big leap into getting a license. Gee, I wonder what this friday at work will bring. :D

I have a modeling project I'm doing on my spare time, but I'll bring the files to work tomorrow and use it for testing and getting into Kray as much as possible. It's exteriors only, but I hope I can get my head around the basic idea of Kray within the day is over.

Salv8or
05-07-2010, 01:03 AM
What you need to do to get nice lighting is use a linear workflow. Basically, gamma correct your output! In Lightwave, add the FPGamma 2.2 image filter, or Michael Wolf's excellent colour correcting pixel filter.

Unless you gamma correct, you will ALWAYS be fighting the renderer. It is absolutely imperative that you have at least a basic grasp on the concept of linear workflow if you want to become an even half-way decent lighting artist. Or at least a half-way efficient one — it is indeed possible to produce nice results even without a linear workflow, but it's a pain in the arse and takes much longer.

So if I put a gammafilter on the output at 2.2, then "tadaaa" the light looks correct/natural (Not nessesary good, but correct), or do you meen if I put a gamma of 2.2 on my output and THEN adjust the light to make it look good?

I know some about LWF how it works, and why ot works, but in the sample above there are no textures theres nothing there that can be "wrong" its jus LW. So its more about the gamma. Is it resanoble to say that I start with a gammacorrection of 2.2 on my output and adjust the textures and lighting from there, I will be in the ballpark?

Iain
05-07-2010, 02:02 AM
Well, Kray actually works with procedurals and shaders. Maxwell doesn't. That makes a pretty big difference to me. :)

Yeah I wasn't trying to compare Maxwell to Kray. I don't think you can.

I was just clarifying that Maxwell doesn't need its own materials etc as was stated earlier.

Captain Obvious
05-07-2010, 02:44 AM
So if I put a gammafilter on the output at 2.2, then "tadaaa" the light looks correct/natural (Not nessesary good, but correct), or do you meen if I put a gamma of 2.2 on my output and THEN adjust the light to make it look good?

I know some about LWF how it works, and why ot works, but in the sample above there are no textures theres nothing there that can be "wrong" its jus LW. So its more about the gamma. Is it resanoble to say that I start with a gammacorrection of 2.2 on my output and adjust the textures and lighting from there, I will be in the ballpark?
Adding gamma correction to a render will not magically make it nice, but it means you won't have to mess around as much with lighting to make it nice.

With a linear workflow, you can light an entire scene with just one light and some radiosity. And it will look natural!

Salv8or
05-07-2010, 02:56 AM
Okey, so if i start out by adding a gammacorrection at 2.2, and have that as a "reference" than if its not looking good, its my fault?
Have I understod this correct?
I just want a starting point, where I know for a fact whats wrong.

So in short, gammacorrect output to 2.2 and then adjust lighting to get the desired result?

alexos
05-07-2010, 03:31 AM
Kray works as a dream for us. We do Architectural work ...

Those are some pretty nice cutouts and I don't recognize any of them. What collection are you using?

ADP.

prometheus
05-07-2010, 05:27 AM
Demo version is in the final stages of testing so we are planing to release it next week - however I can not promise it 100%.

Hope this helps...

A demoversion would be helpful for me to evaluate, and probably convince
our company to rise the level of realism for our gym-machine renders, as well as other personal projects, so I do hope the decision is made to release a demoversion.

Michael

Jure
05-07-2010, 06:12 AM
Thanks a bundel friends.

Trying it as soon as I can.

Nope, still when i want to register i get this:

Message
Error
•You must enter the verification code.

But the site refuses to finish to load, so I geuss im missing the verification code submission form.

Well trying l8r on.

Thnx again.

So you can not see verification code loaded? What browser are you using?

Pamukkedi
05-07-2010, 06:28 AM
I recently bought kray. And I must say, it is a really good renderer.
Absolutely comparable to vray. With one exception: AA is weaker.
Or maybe I am doing something wrong. And that is the other point:
its complicated, and you dont know what you are doing. Its a lot of testing and optimizing. It would be great if there were more tutorials out there, in style " Kray for Dummies". Or maybe a little script with more preset options, and a small and fast preview , just to make life easier.....

geo_n
05-07-2010, 06:36 AM
I recently bought kray. And I must say, it is a really good renderer.
Absolutely comparable to vray. With one exception: AA is weaker.
Or maybe I am doing something wrong. And that is the other point:
its complicated, and you dont know what you are doing. Its a lot of testing and optimizing. It would be great if there were more tutorials out there, in style " Kray for Dummies". Or maybe a little script with more preset options, and a small and fast preview , just to make life easier.....

Did you watch jure's tut vids?

Salv8or
05-07-2010, 06:37 AM
So you can not see verification code loaded? What browser are you using?

It worked today. I use IE8 and the verification didnt load yesterday. Not on work, my laptop or workstation at home. But I registered to day. Thanx for all help.

Larry_g1s
05-07-2010, 08:33 AM
I've been drooling over Kray for over a year, and just made the big leap into getting a license. Gee, I wonder what this friday at work will bring. :DGood deal Ola. Get plugged in on the Kray forum. Kray is powerful, but it's a bit to understand/get use to. The community over on the Kray forum is very helpful. Also check out the recent video tutorials Jure has put up (on the site under Tutorials). ;)

Salv8or
05-07-2010, 12:30 PM
Yes!!!! Finaly, ive got it. I finaly managed to get some sence out of this whole gamma LWF stuff. All it took was to START with applying 2.2 gamma as image filter, and get a correct color picker and "tada". Right on the nuts. Like a baseballbat. No more guessing.
Is there any way to get the gamma correction going on in the pixelfilter insted, so that you can see it while rendering?

Captain Obvious
05-07-2010, 01:11 PM
Is there any way to get the gamma correction going on in the pixelfilter insted, so that you can see it while rendering?
Michael Wolf has a color correction pixel filter that works well for that. Do keep in mind that it technically gives you incorrect results, though! If you work in a heavily controlled linear workflow where things being correct actually matters, it will not work.

Tobian
05-07-2010, 03:52 PM
Can you explain why Captain Obvious?

Captain Obvious
05-08-2010, 06:29 AM
Can you explain why Captain Obvious?
Imagine if you take two AA samples on a certain pixel. One is white, and the other is black. The average would be 0.5, and you gamma correct that to 0.73. Now, imagine that the gamma correction is applied *before* averaging. 1.0 with gamma correction is still 1.0, and 0.0 is still 0.0, so the average would be 0.5.

Basically, the more you use anti-aliasing to counteract noise, the greater the error would be.

Tobian
05-08-2010, 06:43 AM
Ahh ok I see what you mean there. The only problem in the inverse there is that LW's adaptive sampling isn't gamma aware, which results in a lot more brute force, which is why I use the DB&W plugin. If they can solve that issue, then I likely wouldn't especially if the interface included display gamma correction!

Captain Obvious
05-08-2010, 08:21 AM
Really, what they should do is just change the adaptive sampling threshold to be relative instead of absolute! Or maybe have *both* a relative and an absolute contrast threshold. Could be useful.

Tobian
05-08-2010, 08:24 AM
Well or just a gamma correction modifier to the threshold, so you can input the gamma of your intended output. Indeed it could be part of the gamma management system of the next LW edition, automatically.

Intuition
05-09-2010, 10:45 AM
Yes!!!! Finaly, ive got it. I finaly managed to get some sence out of this whole gamma LWF stuff. All it took was to START with applying 2.2 gamma as image filter, and get a correct color picker and "tada". Right on the nuts. Like a baseballbat. No more guessing.
Is there any way to get the gamma correction going on in the pixelfilter insted, so that you can see it while rendering?

I can't remember. Does Kray, when gamma 2.2 is applied in Kray, adjust the gamma values of the sRGB texture maps inverse for you? I don't think it does.

If it doesn't the final look/color of texture maps will always look blown out or faded.

Captain Obvious
05-09-2010, 12:23 PM
I can't remember. Does Kray, when gamma 2.2 is applied in Kray, adjust the gamma values of the sRGB texture maps inverse for you? I don't think it does.

If it doesn't the final look/color of texture maps will always look blown out or faded.
It doesn't, but there is a separate control for image maps and color values.

But keep in mind that for a correct linear workflow, you shouldn't correct the images with the output intent, but rather just make the images linear! That is to say, if you've got an sRGB-encoded image and your output intent is gamma 2.6 (for example), you should NOT apply a gamma of 2.6 to your images if you want to have a correct linear workflow!

Larry_g1s
05-09-2010, 01:07 PM
Hey Captian Obvious, I'm sure I'm speaking for many when I say it'd be great to see some of this explained in some sort of video tutorial(s) of sort. Just spend an hour or so explaining the ins and outs of this stuff and charge something like $10-$15 to download (just to make it worth your time). What do you say?

Captain Obvious
05-09-2010, 02:35 PM
Uh, sure, maybe. I've got a fair bit on my plate right now, but if I can find the time then sure.

Tobian
05-10-2010, 05:19 AM
Cool, I'd look forward to that.. then I can point people at it, instead of explaining it all again :D

gerardstrada
05-11-2010, 12:13 PM
Imagine if you take two AA samples on a certain pixel. One is white, and the other is black. The average would be 0.5, and you gamma correct that to 0.73. Now, imagine that the gamma correction is applied *before* averaging. 1.0 with gamma correction is still 1.0, and 0.0 is still 0.0, so the average would be 0.5.

Basically, the more you use anti-aliasing to counteract noise, the greater the error would be.

Let's consider it depends on how we use the AA at pixel level. If we take two AA samples on a certain pixel where one is white, and the other is black, by using the Antialiasing field, the average will be 72.97% after gamma correction with the pixel filter. But if we apply the gamma correction at pixel level before sub-frame operations, that is to say, by using the Motion Blur Passes field (or Classic Enhanced AA), the average will be 50% at pixel level.



Gerardo

Larry_g1s
05-11-2010, 12:15 PM
Uh, sure, maybe. I've got a fair bit on my plate right now, but if I can find the time then sure.Thanks for considering it Simon.

Captain Obvious
05-14-2010, 06:42 AM
http://www.youtube.com/watch?v=wEbH62a1YqA&feature=player_embedded

How about that?

3dWannabe
05-14-2010, 07:38 PM
I'm a bit annoyed with Worley's reasoning for not including the ability to do LCS from within fprime, and wondering if Kray is indeed the 'promised land' of linear bliss I've been seeking?

Am I correct that

1. Kray provides the same basic 'features' as fprime (possibly faster rendering)?

2. has gamma correction for LCS built in.

3. Works with HD Instance.

Are there any major downsides?

Captain Obvious
05-15-2010, 03:59 AM
1. Kray provides the same basic 'features' as fprime (possibly faster rendering)?
It certainly does not. Kray has no interactive preview rendering features, nor does it let you render with progressive refinement.

It can be faster than FPrime. Sometimes slower, but generally significantly faster if set up correctly.

I don't think Kray works properly with HD-Instance, but I don't really know for sure. However, Kray has its own instancing feature built in with some advantages and some disadvantages to HD-I.

Larry_g1s
05-17-2010, 02:48 PM
It certainly does not. Kray has no interactive preview rendering features, nor does it let you render with progressive refinement.True true. As much as I'm enjoy Kray the more and more I use it (I won't use anything else for interiors), these two features are killer for fPrime.

monovich
05-17-2010, 04:10 PM
I'm a bit annoyed with Worley's reasoning for not including the ability to do LCS from within fprime,

whats his reasoning?

3dWannabe
05-17-2010, 05:21 PM
whats his reasoning?

I believe I saw a link in the last week or so where someone asked him about it, and he thought it was too complicated or confusing for the end user (or something to that effect) to add to fprime.

Apparently, G2 can be used to 'correct' the display of fprime for a linear workflow, but it does it in a bit of an awkward fashion, and only to a precision of 10ths (for the entry field), whereas 100ths are needed.

The steps necessary are shown here:

http://www.newtek.com/forums/showpost.php?p=1012098&postcount=47

3dWannabe
05-17-2010, 05:36 PM
If you ever buy kray start with jure's video tutorial, then read the manual. :)

Are you referring to the tutorials on this page?

http://www.kraytracing.com/wiki/Tutorials

Certainly a lot of excitement about Kray, so I'm interested in learning more about it.

The GI, reflection and motion blurring, DOF (is there bokeh?) sound very interesting.

To see all the top features demonstrated, should I just view the tutorials, or are there YouTube or Vimeo demonstrations showing Kray's power?

Captain Obvious
05-17-2010, 06:30 PM
DOF (is there bokeh?)
"Bokeh" is just Japanese for "blur." In this context, obviously out-of-focus blur. So yes, there is "bokeh" since Kray can render out-of-focus blur. ;)

But yes, there is also control of the aperture shape, if that's what you're asking for. You can use a grayscale image to control the shape of the blur, allowing you to create pretty much arbitrary shapes. A rounded five-blade aperture? Piece of cake. A heart-shaped? Also a piece of cake.

Kray's motion blur is not very good, though. The only way it can render decent motion blur is with full screen jittered sampling, which is not very fast.

3dWannabe
05-17-2010, 08:50 PM
"Bokeh" is just Japanese for "blur." In this context, obviously out-of-focus blur. So yes, there is "bokeh" since Kray can render out-of-focus blur. ;)

But yes, there is also control of the aperture shape, if that's what you're asking for. You can use a grayscale image to control the shape of the blur, allowing you to create pretty much arbitrary shapes. A rounded five-blade aperture? Piece of cake. A heart-shaped? Also a piece of cake.

Kray's motion blur is not very good, though. The only way it can render decent motion blur is with full screen jittered sampling, which is not very fast.

Aside from reading the promo materials on Kray (which don't mention the shortfalls such as motion blur), what does it do well, and what does it do poorly?

Thanks a lot, as I know very little about Kray at the moment.

OlaHaldor
05-18-2010, 01:38 AM
What I've found the little week I've been a happy and curious user, is that the render times are incredibly FAST! I'm stunned by it. Usually I'd hit F9 and go get some food or sit down for ages on Facebook and have a conversation or two. With Kray I feel I can't get that deep into a conversation as I did earlier. :p


I'm having fun learning how to handle this beauty. Motion blur? Pff.. You can add that in post to some extent.

alexos
05-18-2010, 03:34 AM
Aside from reading the promo materials on Kray (which don't mention the shortfalls such as motion blur), what does it do well, and what does it do poorly?

It is pretty much unbeatable for interiors, both in terms of quality and speed, although you do need to come to terms with its apparently endless amount of options. Instancing is rock-solid and fast, though not as versatile as HDInstance. It doesn't really do anything "poorly", but there are some caveats: models need to be watertight, it can't read some nodes, it does use an awful lot of RAM and if it doesn't like something in your scene (the model, usually) it tends to just plain crash.

Usual advice: try it. Actually try it with the scenes you'll find in the repository and make sure you also render those with LW native or FPrime - the comparision will tell you more than I ever could.

ADP.

Captain Obvious
05-18-2010, 03:40 AM
To illustrate how fast Kray can be: I once rendered an interior at 5k, with high-quality GI, area lights and soft reflections on EVERY SINGLE SURFACE. And the render time? Less than half an hour, on a single eight-core machine.

bjornkn
05-18-2010, 04:02 AM
It doesn't really do anything "poorly", but there are some caveats: models need to be watertight, it can't read some nodes, it does use an awful lot of RAM and if it doesn't like something in your scene (the model, usually) it tends to just plain crash.
Watertight? Say you have a lot of columns with no bottom and top faces - will it not render that? Or roof tiles made with only the visible parts, ie with no real volume?
Sounds very limiting if that is what you meant with watertight.

Captain Obvious
05-18-2010, 05:31 AM
Watertight? Say you have a lot of columns with no bottom and top faces - will it not render that? Or roof tiles made with only the visible parts, ie with no real volume?
Sounds very limiting if that is what you meant with watertight.
No, that still renders fine. But Kray is much more sensitive with shoddy geometry than native LW or FPrime.

3dWannabe
05-18-2010, 08:13 AM
No, that still renders fine. But Kray is much more sensitive with shoddy geometry than native LW or FPrime.

Can you give some examples of 'shoddy geometry'?

alexos
05-19-2010, 01:58 AM
Can you give some examples of 'shoddy geometry'?

Lots of two-points polygons, overlaps, self intersections, badly degenerated geometry, weird boolean results... all that will likely make K-ray give you the cold shoulder. For interiors, non-merged points and generic "eyeballed" floors and ceilings might result in all kinds of (usually unpleasant) light leaks. Nothing that can't be quickly fixed with a bit of care, the usual merge-unify and LWCAD's "fix polygons" tool.

ADP.

Captain Obvious
05-19-2010, 02:07 AM
Models that have been built by the typical unskilled 3ds Max artist method of stacking boxes for walls often have problems in Kray.

Kray does not handle non-planars as well as Lightwave does.

3dWannabe
05-19-2010, 07:28 AM
Lots of two-points polygons, overlaps, self intersections, badly degenerated geometry, weird boolean results... all that will likely make K-ray give you the cold shoulder. For interiors, non-merged points and generic "eyeballed" floors and ceilings might result in all kinds of (usually unpleasant) light leaks. Nothing that can't be quickly fixed with a bit of care, the usual merge-unify and LWCAD's "fix polygons" tool.

ADP.
I don't own LWCAD. Is there another solution to the 'fix polygons' tool?

Or - is LWCAD almost a requirement for interiors?

OlaHaldor
05-19-2010, 08:24 AM
It's no requirement, but I'd say the first few moments you spend with LWCAD will make you think "what the heck was I doing all this time without it?"
At least I did, and I haven't regret a second I got it. When I do modeling, I mostly use LWCAD only.

Captain Obvious
05-19-2010, 08:33 AM
It's no requirement, but I'd say the first few moments you spend with LWCAD will make you think "what the heck was I doing all this time without it?"
At least I did, and I haven't regret a second I got it. When I do modeling, I mostly use LWCAD only.
Funny, that's what I thought when I picked up modo. :D

3dWannabe
05-19-2010, 08:41 AM
Funny, that's what I thought when I picked up modo. :D

You create some or all of your models in Modo and bring them over to LW for surfacing/texturing, animation and rendering?

Larry_g1s
05-19-2010, 08:41 AM
It's no requirement, but I'd say the first few moments you spend with LWCAD will make you think "what the heck was I doing all this time without it?"
At least I did, and I haven't regret a second I got it. When I do modeling, I mostly use LWCAD only.lol...totally agree! And that Kray + LWCAD bundle is a great price if you don't own either.


Funny, that's what I thought when I picked up modo. :DOver LWCAD?!?

3dWannabe
05-19-2010, 08:45 AM
Models that have been built by the typical unskilled 3ds Max artist method of stacking boxes for walls often have problems in Kray.


What is the 'skilled' artist method of creating models (if that's not too insanely general of a question)?

Was there a particular Modo tutorial or video that helped you arrive at your techniques?

Captain Obvious
05-19-2010, 11:58 AM
You create some or all of your models in Modo and bring them over to LW for surfacing/texturing, animation and rendering?
Usually, yes.




Over LWCAD?!?
Most of the modelling I do is either cleaning up and editing existing meshes, which I'm more comfortable doing in modo, or building stuff where LWCAD makes no sense, such as 'organic' shapes.

Besides, modo's selection tools are jaw-droppingly awesome. And the macro recording... and the work plane... basically, I work faster in modo than in LWModeler, regardless of the plugins.





What is the 'skilled' artist method of creating models (if that's not too insanely general of a question)?

Was there a particular Modo tutorial or video that helped you arrive at your techniques?
Yes, that is too general and vague! :D Basically, bad*3Ds Max modellers tend to build a wall corner with two boxes, so that either A) they overlap in the corner or B) one box extends a little further than the other. If you're a half-way decent modeller, what you do instead is make the polygons loop around the wall.

alexos
05-20-2010, 02:23 AM
I don't own LWCAD. Is there another solution to the 'fix polygons' tool?

Or - is LWCAD almost a requirement for interiors?

Well, of course you can fix them yourself - it will just take a little longer. Mind, this is all assuming you're starting with a rather (usually imported from other apps) messy model: if you built it directly in modeler and you're not one of them Bad Max Artists it shouldn't need much fixing.

LWCAD isn't exactly "required" but, if you're in archviz, it'll make your life about two orders of magnitude easier. OK, make that three - yes, it's that good.

ADP.

Salv8or
05-20-2010, 04:25 AM
I downloaded the Kray demo version, and I have to say that I realy enjoy working with it. I have som questions thou.

I have some problems getting rid of wall/cealing splotches, ive tried the default settings for interior, made lightportals for the windows and all places where light passes in from the outside. Can someone recomend a good setting? (All models are in scale)

Another thing that bugs me abit is translucensy does'nt match up with lw render.
I have a couple of whitefrosted lights with a iss lightsource. LW seems to have more accurate result in the render (when looking at the translucensy). The lw render have more detail in that area, and it also looks like Kray blurs the photons so that light spreads in to unlit areas of the frostyglass. Any tips/tricks on that?
Ive tried the photonmultiplyer on the lightsources but still have the same result.

Intuition
05-20-2010, 09:49 AM
It doesn't, but there is a separate control for image maps and color values.

But keep in mind that for a correct linear workflow, you shouldn't correct the images with the output intent, but rather just make the images linear! That is to say, if you've got an sRGB-encoded image and your output intent is gamma 2.6 (for example), you should NOT apply a gamma of 2.6 to your images if you want to have a correct linear workflow!

Oh yeah, of course. As a standard I always use the gamma @ 2.2 / sRGB images @ 0.4545 setup. Usually in LW I always adjusted the sRGB images' gamma in the image viewer settings. @ DD there is a method where we use nuke to linearize an image and save it to a separate "lin" folder so that the program does not have to make the adjustment at render time. In maya if I am using Mental ray the framebuffer will adjust all sRGB images for you but with Maya Vray I use gamma nodes after each sRGB image to adjust the values accordingly.

I was just wondering if in Kray you adjust the images inside Kray's interface or with the values in the image viewer? I suppose both could work as long as you only adjust sRGB values once instead of in both places.

Larry_g1s
05-20-2010, 10:19 AM
As a standard I always use the gamma @ 2.2 / sRGB images @ 0.4545 setup. Usually in LW I always adjusted the sRGB images' gamma in the image viewer settings.Intuition, what do you mean by sRGB? Can you explain this further please?

Captain Obvious
05-20-2010, 11:17 AM
I was just wondering if in Kray you adjust the images inside Kray's interface or with the values in the image viewer? I suppose both could work as long as you only adjust sRGB values once instead of in both places.
There is a global control for images, colors, etc, but it will apply the gamma of your choice to ALL images, unfortunately...

Normally, I just either make things linear in Photoshop or Fusion or whatever, or just add TWO layers and set the top one to Pshop multiply. It's not quite accurate, but it does the trick mostly. And it's very easy.

Captain Obvious
05-20-2010, 11:19 AM
Intuition, what do you mean by sRGB? Can you explain this further please?
The vast majority of all JPEGs you run into are sRGB encoded. sRGB is a color profile designed to make images look right on your monitor, that is to say they make the images brighter.


Basically, it goes like this:


Image input is linear.
Computer monitor makes things darker.
Color profile is added to make things perceptually linear again.

Obviously, if you load a profiled/adjusted image into your CG app and then add another profile on top of that, you end up with terrible results.


sRGB is approximately equal to gamma correction of 2.2. Not exactly, but it's close enough most of the time.

3dWannabe
05-20-2010, 11:33 AM
Normally, I just either make things linear in Photoshop or Fusion

Is there a preferred method to linearize in Photoshop and in Fusion for export with as little loss as possible?

Captain Obvious
05-20-2010, 11:39 AM
Is there a preferred method to linearize in Photoshop and in Fusion for export with as little loss as possible?
Keep in mind that most of the time, things don't actually need to BE CORRECT. They just need to look good. Half the time, just sticking a gamma correction of 0.5 on stuff is fine.

bjornkn
05-20-2010, 04:32 PM
But linearizing a color value is a bit more tricky...
There is a node that does the job of linearizing colors/images/gradients etc on the fly, SG_CCNode, or the other way.
And then you could use the Node Image FIlter with the linear->sRGB to get the gamma applied automatically.
Works great, and using linear workflow really helps getting IBL/GI interiors better lit :)

Intuition
05-20-2010, 05:22 PM
Keep in mind that most of the time, things don't actually need to BE CORRECT. They just need to look good. Half the time, just sticking a gamma correction of 0.5 on stuff is fine.

I always use 1.0 divided by target gamma equals sRGB value result. Inverse gamma results in one to one color values at target gamma range.

So 1.0/2.2 = 0.4545

So 1.0/2.6= 0.384

:D

Mental Ray example I made a year ago on XSI discussion.

http://area.autodesk.com/forum/autodesk-softimage/rendering/softimage-gamma/page-3/

http://img228.imageshack.us/img228/1170/furxsi2.jpg

Captain Obvious
05-20-2010, 06:54 PM
But linearizing a color value is a bit more tricky...
1: It's not tricky.
2: It's not necessary.


I don't know about you guys, but I tend to tweak the colours of my textures *anyway*, sticking curve, hue, etc, adjustments on them. There's no such thing as "correct." It's not relevant. The only thing that matters is A) getting the result you expect and B) getting nice results. Everything else is either secondary or completely irrelevant. It DOES NOT MATTER if your textures are linear. The only thing that matters is if they come out looking nice.

bjornkn
05-21-2010, 02:19 AM
It just takes a bit less tweaking and test rendering to get your results if you can build your surfaces/colors in sRGB, linearize and then convert back to sRGB in the end.
But if you have lots of experience you can probably foresee that to get exactly that color you want you need to make it look a lot darker in the first place?

ingo
05-21-2010, 05:27 AM
But linearizing a color value is a bit more tricky...
...

Why should one linearize a color value, they are already in linear Gamma 1. Or have i missed something ?

bjornkn
05-21-2010, 07:25 AM
I don't know what gamma a single color have, if any. But if you input a medium color into SG_CCNode as sRGB (which looks like the one you want in the output) the linearized output shows a much darker color. And when you render in linear space and then use that node for processing the output back to sRGB it looks just like when it was a color in the color picker. If used with no conversion/linearization it looks much paler.
Why should a colored pixel in an image behave different from a pixel with a color value given directly?
If you bake a procedural to an image in sRGB, wouldn't you have to linearize that procedural just as much as the baked image?
But I guess this has nothing to do with the original "Kray" subject?

Pavlov
05-21-2010, 07:56 AM
I recently bought kray. And I must say, it is a really good renderer.
Absolutely comparable to vray. With one exception: AA is weaker.
Or maybe I am doing something wrong. And that is the other point:
its complicated, and you dont know what you are doing. Its a lot of testing and optimizing. It would be great if there were more tutorials out there, in style " Kray for Dummies". Or maybe a little script with more preset options, and a small and fast preview , just to make life easier.....

Hi,
my suggestion is to avoid Kray's AA settings (FSAA OFF) if not really needed.
I use nearly always a Mitchell AA in Grid mode with FSAA mode ON. FSAA makes a full evaluation of the pic and will resample it N times, where N is Grid Size parameter.
So, you have only Grid Size to tweak. Start from 2/3 for test pics, use 4 (if you are using cache irradiance) to 6 (if you turn IC off, since you'll get more noise) for final stills, and more for animation (i had to use up to 10-12 in some extreme cases).
For sure you can optimize times if you dig settings and make a lot of tests, but in my experience this solution is a winner for all cases.


Paolo

Pavlov
05-21-2010, 07:58 AM
I don't think Kray works properly with HD-Instance, but I don't really know for sure. However, Kray has its own instancing feature built in with some advantages and some disadvantages to HD-I.

Kray 2.1 works perfectly with latest HDi.
It has to be said that HDi is several times slower than HDi instancing, being volumetric. Unless you need HDi's placement tools, just use Kray's instances.

Paolo

Pavlov
05-21-2010, 08:10 AM
I have some problems getting rid of wall/cealing splotches, ive tried the default settings for interior, made lightportals for the windows and all places where light passes in from the outside. Can someone recomend a good setting? (All models are in scale)


Forget Lightportals. Just use Lightmap mode in Photons tab (you've two near buttons: Photonmap and Lightmap - always use Lightmap, unless you are sure you know why you need Photonmap mode).
Then use Krays' Phisical Sky and you're done. If you need more control, use whatever you like as backdrop (color, gradients, HDR), use an arealight as Sun and light will naturally enter from your windows and bounce around.


Another thing that bugs me abit is translucensy does'nt match up with lw render.

Forget LW's translucency, Kray does it *right*, LW doesnt.
LW computes translucency just for direct lighting (unless you use nodes), Kray computes translucency even for indirect lighting (skylight and bounced light) like it happens in nature. Get used to it. If you want to get similar results to LW's, just lower translucency and raise light's value.

Paolo

3dWannabe
05-21-2010, 08:49 AM
I was about to purchase Kray, but realized that it won't work with exrTrader for multi-pass renders.

Is this a concern to other users?

Possibly Kray could increase its user base by providing this, and the increased revenue would benefit even those who don't need it.

Captain Obvious
05-21-2010, 09:07 AM
FSAA makes a full evaluation of the pic and will resample it N times, where N is Grid Size parameter.
Technically :p each pixel gets N^2 samples, with N being the grid size. So a setting of 3 is actually a 3x3 grid, ie 9 samples.




I was about to purchase Kray, but realized that it won't work with exrTrader for multi-pass renders.

Is this a concern to other users?
Not in the least, because Kray has its own support for multi-layer output.

3dWannabe
05-21-2010, 09:18 AM
Not in the least, because Kray has its own support for multi-layer output.

Can I use Janus with Kray and output exr files of all the passes in a very automated fashion?

Captain Obvious
05-21-2010, 12:21 PM
Can I use Janus with Kray and output exr files of all the passes in a very automated fashion?
I don't know if Janus is compatible with Kray, but if all you need is stuff like... say... reflections, indirect illumination, etc, then you get that built-in with Kray. Literally, it's just a matter of clicking a checkbox or two. It can't render to layered OpenEXR, but multi-file Radiance sequences has always sufficed for me.

3dWannabe
05-21-2010, 12:48 PM
I don't know if Janus is compatible with Kray, but if all you need is stuff like... say... reflections, indirect illumination, etc, then you get that built-in with Kray. Literally, it's just a matter of clicking a checkbox or two. It can't render to layered OpenEXR, but multi-file Radiance sequences has always sufficed for me.

There's a thread on the Kray forum where the developers said OpenEXR is on their list (just not sure exactly the priority).

I'm sure your workflow works well for you and for other existing Kray users, but it still might open Kray up to a number of users who don't use it now - but who do use OpenEXR.

Oh well, just had to ask.

Pavlov
05-21-2010, 04:50 PM
Technically :p each pixel gets N^2 samples, with N being the grid size. So a setting of 3 is actually a 3x3 grid, ie 9 samples.


Eheh.. you're true, technically speaking. But even if squared value thing is technically true, i'd keep it simpler in an introductory talk: one may think a FSAA grid 4 (16samples) takes nearly double as gid 3 (9 samples), but it doesnt work exactly this way.

bye
Paolo

gerardstrada
05-22-2010, 03:41 AM
I don't know what gamma a single color have, if any.
It depends on several aspects. If it's from a color picker from an unaware color management (CM) app, it will be the gamma of the monitor profile. If it's from an 8-bpc image, it will have the gamma of the color space in which the image was created/saved. If the format or app has some CM capabilities, you might know it by checking the color profile embed/taged in the image file.


But if you input a medium color into SG_CCNode as sRGB (which looks like the one you want in the output) the linearized output shows a much darker color. And when you render in linear space and then use that node for processing the output back to sRGB it looks just like when it was a color in the color picker. If used with no conversion/linearization it looks much paler.
Yep. The same thing happens with image maps. The difference between sRGB and 2.2 gamma for linearization can be critical in dark areas of images or dark textures when we gonna use real sRGB gamma in the compositing package. Since sRGB gamma have a linear segment near the toe of the curve, if we linearize with 2.2 gamma, we would be darken too much those dark areas and loosing detail there. Sometimes the increased contrast could look good, but sometimes not (if it's not the purpose of the color-grading treatment). In those cases, I've found that the correct/better/easier way is using real sRGB gamma for the linearization process.


Why should a colored pixel in an image behave different from a pixel with a color value given directly?
They behave in the same way if they are in the same color space and gamma.


If you bake a procedural to an image in sRGB, wouldn't you have to linearize that procedural just as much as the baked image?
Yes. But the thing is that the color you choose in the color picker might not be in sRGB gamma. Monitors have their own color spaces and gamma and if your system is working with its own monitor profile, sRGB gamma will differ from monitor's gamma.


But I guess this has nothing to do with the original "Kray" subject?
Of course it has to do. Not only with Kray but with any other renderer out there :)



Gerardo

geo_n
05-22-2010, 05:25 AM
I was about to purchase Kray, but realized that it won't work with exrTrader for multi-pass renders.

Is this a concern to other users?

Possibly Kray could increase its user base by providing this, and the increased revenue would benefit even those who don't need it.

I requested exr support over st kray forum. They might implement their own. My biggest request is alpha and matt support. I hope they can work on it asap after 2.1.