Tips & Tricks for Iray for newbies......

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  • kyoto kidkyoto kid Posts: 39,119
    edited December 1969

    It's the trade-off with an unbiased (physics based) rendering engine.

    I tried out Reality/Luxrender, and... holy dear bleepity. It took me 10-15 hours to get a very grainy terrible image.


    ...yeah same here. 9 -11 hours later and I'd still have far more noise than I would in 45 min with Iray

    Then with both the Daz 4.7 and Reality4 updates (which were both released less than 12 days apart), I found that when opening older scenes in Reality none of the surfaces would appear in the Reality UI materials tab. Eventually there was a workaround but it was clumsy and each time a new patch for Reality was issued I had to reset the surfaces to the Lux properties all over again. Got pretty old after a while. Basically you had to create a "new" scene for everything to work right.

    Ended uninstalling the whole mess.

  • Oso3DOso3D Posts: 14,716
    edited December 1969

    Thankfully I discovered it was unusable for my purposes in time to ask for my money back.

  • SickleYieldSickleYield Posts: 7,597
    edited December 1969

    I have to say Holy Dear Bleepity is about the best forum expletive I've ever heard.

  • spearcarrierspearcarrier Posts: 635
    edited March 2015

    So far I like iray better than Lux, although Lux has one thing over iray: the ability to save and stop a render and come back to it, pick up where you left off essentially. Can't do that with iray. But on the other hand, with Lux it was ... way too complicated... Probably these days I'd be able to follow it better, I admit, but back then? I was a guppy trying to swim with whales. Now I'm a minnow trying to swim with whales. Ha.

    I don't have a NIVIDIA card. I'm running 4 cores with a dying motherboard and a radeon card. And yet I can't just go and kick rocks. I keep coming back to it. LOL.

    I managed to do a render with a single sun in the sky under 2 hours and it looked great. The render I've been fighting for 2 days now - a gift for my readers, I hoped - is a complete mess.

    I'm thinking the architectural and caustic optimizations have a lot to do with the slow speed. I had those turned off for my happy field of flowers picture. Even with as many lights as I have in this render, it doesn't wanna go. Which is frustrating because I think I beat the old hair render issue everyone is talking about. Maybe. I can't see to tell.

    Post edited by spearcarrier on
  • SickleYieldSickleYield Posts: 7,597
    edited December 1969

    So far I like iray better than Lux, although Lux has one thing over iray: the ability to save and stop a render and come back to it, pick up where you left off essentially. Can't do that with iray. But on the other hand, with Lux it was ... way too complicated... Probably these days I'd be able to follow it better, I admit, but back then? I was a guppy trying to swim with whales. Now I'm a minnow trying to swim with whales. Ha.

    I don't have a NIVIDIA card. I'm running 4 cores with a dying motherboard and a radeon card. And yet I can't just go and kick rocks. I keep coming back to it. LOL.

    I managed to do a render with a single sun in the sky under 2 hours and it looked great. The render I've been fighting for 2 days now - a gift for my readers, I hoped - is a complete mess.

    I'm thinking the architectural and caustic optimizations have a lot to do with the slow speed. I had those turned off for my happy field of flowers picture. Even with as many lights as I have in this render, it doesn't wanna go. Which is frustrating because I think I beat the old hair render issue everyone is talking about. Maybe. I can't see to tell.

    Both of those will slow the render down significantly. Don't use the caustic sampler unless you're really in closeup on multiple caustic items, and I really haven't yet found a situation where the architectural sampler was worth it.

  • spearcarrierspearcarrier Posts: 635
    edited December 1969

    The first render I did I noticed a very small difference with the light when I turned on the architectural sampler. The image had sunshine coming in to bounce off my focus and a bench. I somehow thought I had to have caustic on when dealing with water, which this latest render has. It's an image I've been trying to do for two years now. I'm all excited that I can finally do it the way I've been seeing it, even if it is only 600 pixels wide. I'll turn off caustics, see what happens.

    I'm trying to find something about "max path length", because with octane they say not to have it too low (5 was too low) but can't really find what it's all about.

  • tl155180tl155180 Posts: 994
    edited December 1969

    I've also noticed that the textures you have in the scene will have a large impact on render times. In an empty scene with just the Enviroment Dome one of my G2F figures takes less than 3 mins to render while another one takes over 6 mins.

    Also discovered that, whilst you can apply a skydome texture to the Environment Dome map, it has the effect of seriously smothering the light from the dome and turns it the colour of the texture, leaving virtually no sunlight effect at all.

    Unless I'm doing something wrong, of course... which is not unlikely :)

  • Oso3DOso3D Posts: 14,716
    edited December 1969

    One thing I discovered quite by accident is that putting high white translucence on shirts makes them look very much like wet shirts.

    I can't show you because it'd be, er, not allowed here.

  • SickleYieldSickleYield Posts: 7,597
    edited December 1969

    tl155180 said:
    I've also noticed that the textures you have in the scene will have a large impact on render times. In an empty scene with just the Enviroment Dome one of my G2F figures takes less than 3 mins to render while another one takes over 6 mins.

    Also discovered that, whilst you can apply a skydome texture to the Environment Dome map, it has the effect of seriously smothering the light from the dome and turns it the colour of the texture, leaving virtually no sunlight effect at all.

    Unless I'm doing something wrong, of course... which is not unlikely :)

    Yep. Iray is known to be slowed more by large textures than by refraction (unlike 3Delight in DS).

    HDR maps are always the best for environment lighting. I still use the others occasionally but not in a scene where I need them to act as close background to a character.

  • tl155180tl155180 Posts: 994
    edited December 1969

    tl155180 said:
    I've also noticed that the textures you have in the scene will have a large impact on render times. In an empty scene with just the Enviroment Dome one of my G2F figures takes less than 3 mins to render while another one takes over 6 mins.

    Also discovered that, whilst you can apply a skydome texture to the Environment Dome map, it has the effect of seriously smothering the light from the dome and turns it the colour of the texture, leaving virtually no sunlight effect at all.

    Unless I'm doing something wrong, of course... which is not unlikely :)

    Yep. Iray is known to be slowed more by large textures than by refraction (unlike 3Delight in DS).

    HDR maps are always the best for environment lighting. I still use the others occasionally but not in a scene where I need them to act as close background to a character.

    Thanks SickleYield (your deviantart Iray tutorials have been very helpful by the way). Yeah, I don't have any HDR maps yet - do they still block out the sunlight like skydome maps do?

    I have all these skydomes in my product library and I'm determined to find a way to use them with Iray. Obviously you can't use them as normal, because the skydome just blocks out the light from the Environment Dome and you're left in darkness.

    I already mentioned above what happens if you use a skydome texture on the Environment dome map.

    If you turn the skydome itself into an emissive surface and (I just discovered that this is the critical part) add the skydome texture map to the glossy color and emission color maps, then you can get the old skydome look and have some nice environmental lighting as well - but sadly you're still missing the sunlight then because it doesn't penetrate the skydome. Hmmmm.....

  • SickleYieldSickleYield Posts: 7,597
    edited December 1969

    It does. I think the reason is probably because a lot of HDRs intended for environment map use have a sun or moon on them already that it could clash with? I'm not sure.

  • tl155180tl155180 Posts: 994
    edited December 1969

    It does. I think the reason is probably because a lot of HDRs intended for environment map use have a sun or moon on them already that it could clash with? I'm not sure.

    Unless the Iray Environment dome has a specific area on it for 'creating sunlight / allowing it through' and when we apply a skydome texture or HDR map to the dome we are inadvertently covering that area up? Or does that sound stupid? I dunno...

  • Oso3DOso3D Posts: 14,716
    edited December 1969

    Any tips for proper sclera settings? Mine are coming out way too white.

  • SzarkSzark Posts: 10,634
    edited December 1969

    I haven't kept up with this thread and at present my PC is busy rendering and slow so I cannot search myself. Anyway it struck me that I don't know which way North is when a camera is at dead centre. Anyone ask this yet?

  • Richard HaseltineRichard Haseltine Posts: 87,359
    edited December 1969

    If the camera cube shows Front you are looking north, You can cmd(Mac)/ctrl(Win) click the reset icon, at the bottom of the column of camera control icons next to the cube, to point the camera due north.

  • SnowSultanSnowSultan Posts: 3,355
    edited December 1969

    I wrote a journal about using HDRIs in Iray and how to get more of a familiar 3Delight look if you're not trying to make photorealistic renders but want the material advantages of Iray. Maybe there's something in it that could be useful.

    http://snowsultan.deviantart.com/journal/Old-school-HDRI-lighting-in-Iray-523712116

  • SzarkSzark Posts: 10,634
    edited December 1969

    If the camera cube shows Front you are looking north, You can cmd(Mac)/ctrl(Win) click the reset icon, at the bottom of the column of camera control icons next to the cube, to point the camera due north.
    Thanks Richard that is easy to remember. :)
  • tl155180tl155180 Posts: 994
    edited December 1969

    Is there anyone out there who owns either http://www.daz3d.com/land-of-the-ice-cold-sun or http://www.daz3d.com/dry-mud-desert and knows how to make them look right in Iray please?

    They look great in 3Delight, but in Iray the ground shaders look all tiled and blurry. I tried the Iray UberBase and I've been fiddling around with all the settings, but can't find a way to make it look good. Any help would be most appreciated, thanks.

  • Jack238Jack238 Posts: 117
    edited December 1969

    I wrote a journal about using HDRIs in Iray and how to get more of a familiar 3Delight look if you're not trying to make photorealistic renders but want the material advantages of Iray. Maybe there's something in it that could be useful.

    http://snowsultan.deviantart.com/journal/Old-school-HDRI-lighting-in-Iray-523712116

    Thanks SnowSultan. Nice journal. I found it helpful and easy to read.

  • LunaseasLunaseas Posts: 4
    edited December 1969

    I really LOVE this thread. I still will experiment for myself a bit, but these tips have been so helpful. I have attached a few renders I did mostly with candles and purposely darker settings.

    studyglow.jpg
    975 x 741 - 489K
    study.jpg
    1000 x 823 - 343K
  • SnowSultanSnowSultan Posts: 3,355
    edited December 1969

    Thanks Jack, I'm glad it was easy enough to understand. :)

  • spacecat56spacecat56 Posts: 50
    edited December 1969

    ...I worked out that at the current rate my (rather small) render would take around 12 and a half hours to complete if left to its own devices.

    In case no one has mentioned this, the "progress" is definitely NOT linear... when it is dominated by convergence, it is showing the percent of the limit reached (e.g. if 9.5% converged and the limit is set to 95% you are "10% done"), but convergence is very slow at the start and accelerates through the render. So e.g. 30 minutes to reach 5% does NOT lead to a 10 hour render...

  • spacecat56spacecat56 Posts: 50
    edited April 2015

    ...
    2. Turn off your CPU in the render settings if you have one or more good graphics cards, the CPU will actually slow render down.

    That depends a bit on what components you have...

    My primary desktop has a 8-core 5960x running at 3.7GHz and a GTX 970 video card. Test renders are about 15% faster with CPU and GPU, vs. GPU alone. Of course, that 15% is bought at the cost of more than doubling the power consumption...

    Post edited by spacecat56 on
  • SickleYieldSickleYield Posts: 7,597
    edited December 1969

    thetom56 said:
    ...
    2. Turn off your CPU in the render settings if you have one or more good graphics cards, the CPU will actually slow render down.

    That depends a bit on what components you have...

    My primary desktop has a 8-core 5930x running at 3.7GHz and a GTX 970 video card. Test renders are about 15% faster with CPU and GPU, vs. GPU alone. Of course, that 15% is bought at the cost of more than doubling the power consumption...

    I'll go back and change it. I retested and it's apparently no longer the case; I don't know what I was doing to get that result earlier. I do get a slight increase in speed with my CPU on.

  • Arnold CArnold C Posts: 740
    edited December 1969

    Any tips for proper sclera settings? Mine are coming out way too white.

    You can try and change the Diffuse Color to tone the brightness down. On Victoria 6 I changed the "Base"/"Diffuse"/"Reflection"/"Base Color" value for both Sclera and Iris (which came out too bright for my taste, too) from RGB 255-255-255 to RGB 210-210-210.

    Below are some test renders, from left to right:

    RGB 255-255-255 RGB 210-210-210 RGB 200-200-200

    Victoria_6_Skin_Setup_A-2.jpg
    1764 x 582 - 126K
  • SondheimFreakSondheimFreak Posts: 11
    edited December 1969

    Hi-

    I'm hoping someone might be able to steer me in the right direction. I've searched this thread and reviewed http://www.daz3d.com/forums/viewreply/782511/ (#295 specifically, mentions portrait type settings for blurred background). What I'm trying to do is use DOF in Iray, and I can't seem to make it work.

    I've tried high fstop/low shutter speed, vice versa, I have DOF enabled for Camera 1, used varying Focal Distance/Fstop...I just can't figure out what I'm doing wrong because every render still has a perfectly clear background. screenshot Screenshot 2015-04-14 11.03.53 shows how my current settings are (after playing with them many, many, many times) and screenshot S041215B_test shows the result (based on current settings).

    What am I missing/doing wrong? Any assistance is greatly appreciated.

    Thanks!

    S041215B_test.png
    673 x 882 - 836K
    Screenshot_2015-04-14_11.03_.53_.png
    1920 x 1080 - 658K
  • Oso3DOso3D Posts: 14,716
    edited December 1969

    What I find helpful is to go into Perspective mode, and select the camera.

    That will show you where the focus is, and the rough range of what's in focus/out of focus.

    Also f/stop shouldn't be negative.

  • TJohnTJohn Posts: 10,789
    edited December 1969

    Your F-stop is in the negative range. move it in the positive until the subject of your render is inside the F-stop "Box". Then the rest of the render will be out of focus,
    HTH.

  • Oso3DOso3D Posts: 14,716
    edited December 1969

    I would also highly suggest keeping f-stop between 8 and 22, and then adjust focal length (to make the fore/back range appropriate) and then focal width to get your scene scaled properly in frame.

  • ZarconDeeGrissomZarconDeeGrissom Posts: 5,408
    edited April 2015

    Also... The F-stop in the render tab, is for light levels only.

    The settings in the parameters tab for the 'Camera' are for the DOF effect (And do not effect light levels).

    Just an FYI, for others that stumble across this.

    Post edited by ZarconDeeGrissom on
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