Glass window not showing correctly


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I am working on a small TI job. In the reception area job we added a 42" high wall with 42" glass panels above.

The existing doors in this room have glass panels. When I did a rendering of the new wall with glass panels above

the glass doors in the background have a crackling appearance. It should be clear glass.

 

I have attached the file so you can see what I am talking about. Does anyone know why this is happening and

how to correct it ?

 

Thanks,

 

Mike

 

 

PTI_Technologies_Remodel.plan

Office Rendering.jpg

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Thanks guys for the help. I tried Graham's suggestions and turning off Photon mapping worked.

 

I did not try turning off all of the lights yet. I see in the rendering you posted that it still looks like

the fluorescent lights are still turned on. If you turned off the lights in the rendering how did you

get the fluorescent light to appear to be turned on ?

 

Thanks,

 

Mike

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On 12/9/2016 at 11:20 AM, DRAWZILLA said:

 

Mirrors will also do this , you cannot have mirrors reflecting into other mirrors.

 

 

 

???  The attached was either X7 or X8.  It's all about the lighting.  One bad light position or light against the wrong material and fireflies and glass ripples will never ray trace away.

20150218_Aiken_04_Gym_01_FB.jpg

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I should have said "Renders" in my posts, I really don't do a lot of raytraces, but when I do they are the fast "Crappy" ones, under 3 min. .   I put out a lot of construction doc.s for the building departments and they don't care about pretty pictures. I use some Rt's for the client prelim's only.

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Thanks everyone for your help. 

Jon, I like your gym rendering. I can see that you are looking through several mirrors with the crackling effect.

You said that " It's all about the lighting.  One bad light position or light against the wrong material and fireflies and glass ripples will never ray trace away"

Is there there certain distance that we should keep our light sources away from glass and mirrors so we do not get the ripples in the ray trace ? 

What other materials would be negatively effected by a bad light position ?   

 

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Mike, I'm not sure what's going on with your model.  It's just grainy in rt.  That leads me to believe there is a bad material(s) somewhere within the plan.  A couple things I did notice.  Turn off all lights not directly influencing the view.  Try doing what Perry suggests and use light sources for the majority of the illumination and fixture specific lights only where they are visible in the camera view.

 

Sorry, I don't have the time to hunt down the offending material--it can be a challenge. 

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Thank Jon for your help. Now I am having a problem with the stainless steel refrigerator and dish washer appearing to be black in the break room.

There are two areas of remodel. The first being the waiting room which you have been helping me out with and the other being a break room.

 

The break room is off to the right of the partition wall with glass above and is open to the waiting room. I did both ray traces about the same time.

The break room worked fine. The waiting room was the problem area. Now that I have turned off all of the lights in the waiting room and added light

sources, the wait room is looking good. Now the stainless steel appliances in the break room are not showing correctly and appear to be black.

None of the lights were turned off in the break room. I am using the same camera view as before. I made no changes to the break room.

 

Why now would the stainless steel appliances not show correctly ?

 

Thanks,

 

Mike

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When I looked at this it appears that the grid ceiling light fixtures are the issue. There is always a high risk of these speckles in the glass when the light source has to pass through a lights lens or transparent shade and then through more transparent materials such as glass in windows and doors. In this plan the light from it's source is passing through 3 transparent materials before getting to those back offices. If the lights are point type and photon mapping is on that's a huge number of calculations which is also compounded by the number of light sources. Theoretically, things should get cleaner as the number of passes increase however, this plan takes so long to run even a single pass I'm not sure one would have the patience to wait to see what this would look like after say 100 passes. Also, the calculated corrections per pass follow the law of diminishing returns, as each pass completes the apparent correction lessens.

 

Graham

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Graham, I turned off all the lights, merged the multiple "Glass Standard" materials and replaced fresh from the library, dropped a camera view directly in front of the large office window, and added four light sources (inside office, outside office, left of camera, and behind camera) and the shot was very grainy after 10 passes.  I tried w/wo photons and caustics--no change.  

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Jon - Without seeing your exact plan it's difficult to know exactly what is happening. I did post renderings earlier on that showed the results I obtained, all of them had some form of light source. Also, point lights are more problematic than spot lights as their light paths are calculated differently. This issue can also be affected by the balance between a light sources intensity and the ambient light source intensity. It's very easy to have the lighting set where if you think of this in photographic terms the pic is way over or under exposed. Too much light in the room will overwhelm the Raytrace engine, it just can't adjust no matter the number of passes.

 

Graham

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Mike - The way your lights and materials are set you will need to run your break room with Photon Mapping turned on. Would suggest turning off those grid ceiling lights so you will be able to Raytrace in a reasonable length of time. If you want to run this with Photon Mapping off then you will need to change your lighting and most likely the stainless steel material/properties so they do not show as black. When Photon Mapping is turned on the Raytrace engine is calculating multiple light bounces and as such your stainless steel will show correctly due to light bouncing off of the walls, floors, ceilings and other objects in the room. When Photon Mapping is turned off then this light bouncing is not calculated, to get the stainless to show correctly you would need to add additional lights specifically directed at the stainless steel or you would need to change the stainless steel properties/material to compensate for this.

 

Graham

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