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Dave_Donley

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Posts posted by Dave_Donley

  1. If you do the radiosity solution within a viewport and the document pref is on to save the cache with the file, then the radiosity solution will stick around with the viewport as long as you don't change something that invalidates the solution. If the viewport cache is saved then it won't require that the radiosity solution be regenerated, just rerendered when you change the sheet layer DPI.

    I like PNG because it is a "lossless" format unlike JPG but JPG is a bit smaller. If you have a rendered viewport you can copy and paste the image to another program (like Preview on the Mac) then save it out as some other format.

  2. What class is the directional light in? Is the class on?

    Is the directional light within a symbol? Is the symbol's light brightness % (in the Obj Info palette shape pane) set > 0%?

    Is the brightness set to use an emitter? Is the emitter brightness set to a decent brightness?

  3. Hello again Jim:

    I would probably change the lux values. I see the dimmer as something like an electrical dimmer switch, to change the values to temporarily lower values, rather than the main way to change the light brightness. It would be nice to remain grounded to physical units - that way you wouldn't get in trouble by specifying a 50 watt bulb running through a 1000% dimmer!

    Since I am a gearhead and I know what everything does I often use custom. I use it because I can turn off things to control the speed. Usually with a radiosity scene you can set a few switches or sliders and save hours of solution time. I can usually generate a decent quality solution in 10 minutes and the whole render in 1/2 hour by adjusting the radiosity settings and mainly by controlling which objects participate.

  4. Hello again Jim:

    I always use auto exposure. When it is on you do not have to worry about absolute brightness as long as your lights are consistent relative to each other. The easiest way to keep them consistent is to use accurate values for all of them. I do not mix the % brightnesses with the accurate brightnesses in the same scene. Auto exposure also shows indirect lighting better than not having it on, because the effects can be pretty dim and subtle.

    Propstuff and I have been figuring out useful lighting techniques (pre-radiosity days even!); his conclusions are to use a smooth falloff and no auto exposure. My recommendation is to use sharp falloff and auto exposure all the time.

    One thing I also recommend is to use the 16 electrical accurate lamp symbols from the Libraries folder. These have accurate light values assigned to them already. They use sharp falloff and will require auto exposure because of the brightness values.

    If you can get the file to me that would help a lot.

  5. In the Custom RW and Custom Radiosity options is a checkbox called "Auto-Adjust Exposure", when it is on RW adjusts the pixel luminances so that the brightest and dimmest parts are more visible in the image. This is on by default for the radiosity modes, and is an option for CustomRW mode.

    Lux is lumens per square meter, and is useful for area lights and directional lights. It is helpful to put both the "sun" directional light and the "sky" area lights into lux, so that the balance between the cool and warm lighting can be controlled in a straightforward way. It is also very useful to put area lights in lux because then windows of different sizes will have consistent even brightness. The only time I would use lumens for an area light would be if it were some kind of panel with electric lights behind it of a known total lumens value.

    I would set the dimmer to 100%, otherwise you are seeing 75% of 20000 lux. Your other settings are fine.

    Are you mixing electrical and natural lighting in the same rendering? I set the directional light to a wamr color because the sun appears warmer than the sky.

    If you have the white balance set to 5500, lights with K lower will appear more yellow or orange, and lights higher than 5500 will appear blue. Each layer an viewport has its own white balance setting; each should be set appropriately for the lights that are on in the layer/viewport.

  6. Hello Jim:

    It is hard to say why the colors are changing without seeing the file. My guess is that it is the auto exposure, which is on by default in FQ radiosity mode.

    I just did a lighting presentation for the NYC user's group last week and I'm trying to record this in a form that can be used here on the forum. My recommendation for interior lighting for is just what you tried - 20000 lux for area lights just inside the window glazing (so the glazing, mullion, etc don't cause noisy shadows), set to a very pale blue color (I only use color temp for electric lights, it is too colorful with natural lighting), and a directional light with very pale yellow and also 20000 lux. You may try changing the directional light to footcandles then back to lux to make sure it "sticks".

    I do not use ambient light at all with radiosity as it just introduces a gray haze to the image.

    If you can send me the file I might be able to help more. The large size is either from the radiosity solutions being saved with the viewport cache (you can change this in the document prefs) or a lot of images in the file. Rendered viewports with caches can be quite large.

    Does the layer and viewport lighting options white balance color temperature match the lights' color temperatures?

    HTH,

  7. Hello ptarmigan:

    Is this a complicated model? How much RAM does your machine have?

    The reasons triangles might not show up are if the sizes are small enough that a lot of triangles will be generated then they won't be shown (it would slow down the preview a lot), or if the largest surface in the view is under some other surface or overlaps with another surface.

  8. Hello sfatelier:

    I would say the most controlled way to output a rendering is to create a viewport. The sheet layer where the viewport resides has a DPI value to control pixel resolution. Choose View->Create Viewport. Then in the Obj Info palette with the viewport selected click Update. After the viewport is rendered it behaves as a bitmap - it won't need to be rerendered during printing.

    HTH

  9. Hello Jim:

    If you uncheck Create Plug-In Object in the Create Image Prop dialog box, it will create a textured 3D polygon rather than an Image Prop plugin. You can then rotate the polygon any which way in 3D.

    This is a quick way to make things like paintings for the wall, rugs, etc.

  10. Hello jeffroyer:

    Try the electrical lamp symbols in the Libraries->Objects Imperial->16_Electrical_Accurate_Lamps.mcd file. There are pre-made bulb symbols in there that will help you.

    The easiest way to get a lampshade that will glow is to use the Translucent reflectivity shader in a texture resource; also turn off cast shadows for the texture. Surfaces with this texture will light up from behind.

    This same setup is used to make the electrical accurate lamp symbols' surfaces light up.

    The bulb symbols use color temperature, so you should go to the Layer or Viewport Lighting Options dialog and set the white balance temperature to 3400K (Electrical). Also, if the bulbs are too bright you can either use auto exposure in the render mode or turn the brightness down using the symbol's brightness multiplier slider in the Object Info palette.

    HTH!

  11. If you are using image props for the trees it sounds like they were created using Contant reflectivity, which will cause them to not change brightness when they are in shadow. You can either re-create them with that option unchecked, or go to the texture resources that the props use and change the Constant reflectivity shader to None.

  12. Hi petervg123:

    Do you have a layer linked in multiple times, or otherwise overlapping geometry? One way to tell this is to select one of the layer links, unlock it and delete it. If the geometry remains then it is linked in multiple times and can show rendering artifacts like the one you mention.

  13. Hello Pete:

    For the mullions, it looks like they are being missed by the antialiasing. Try rendering at a higher DPI (more pixels) and they should render continuous.

    For the spotty roof, is the roof layer linked in multiple times? I.e., If you select and delete the roof layer link, does the roof still appear?

    HTH,

  14. Hi propstuff:

    Piranesi export is a 3D operation, it needs the depth info to do its fancy plane locking, etc. tricks. It is actually doing a rendering with depth to produce the EPix file.

    To get a truly 2D image into Piranesi, maybe you can import it as a PNG or other. You will not get the 2.5D features for such an image, though.

    HTH,

    Dave Donley

    dave@nemetschek.net

  15. Hi afca:

    The texture resources that are created for image props have a 1" size. The first thing you might want to do is change the size to something that matches your objects more closely.

    It is otherwise perfectly appropriate to let the Create Image Prop menu command create a texture resource for you and then throw away the prop itself.

  16. I agree with George, an image prop would be the quickest way to do it. You're basically automating the creation of a textured 3D polygon with the usual image prop options deselected. This is also a quick way to make posters, rugs, etc.

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