Shaderlight

Novice questions on lighting

 
eddiemafa
Total Posts: 8

I apologize for the coming dumb questions but I am a novice at Shaderlight.

I am trying to render a scene from the outside but would like to see part of the interior of the building as well. I know that for achieving that I will have to place some simulated light inside.

I did that but am not being able to see the exterior and the iluminated interior at the same time. If I set the Lighting control at Physical Sky I do not see the interior and if I set it to Artificial Light Only I do not see the exterior. As far as I know, I should be able to see both situations. I must be doing something wrong.

Is there a way to see both at the same time? How? Or would I have to make two renders and combine them in postprocessing?

Thanks for the help.

Edson

awaddington
Total Posts: 390

Hi Edson,

This is a common question.

The issue is the contrasts between the intensity of the sun compared to the interior lighting.

As the exterior dims (or interior brightens), the interior will become more prominent.

In general, make certain you have skylight portals on all of your windows (this ensures the correct amount of sunlight enters the room) and make sure you have enough light inside. 

A handy rule of thumb is to multiply the square feet of your room by 0.01587—this will tell you the number of point lights set at 125 candella you will need to simulate the light of an average living room. ad a couple extra lights fpr brighter rooms, but that is agood starting point.

This may still look dark in contrast to the sun, but will be realistic.


There are other settings and tips for both Sketchup and Shaderlight that may help but, I cannot provide specific advice without more information.  If you can send a screenshot of your scene, settings and information about how you are lighting the interior (number/type of lights and their settings) and a render of your scene, that will help significantly.


Good luck!

eddiemafa
Total Posts: 8

Hi Andrew,

Thanks for the reply. I am attaching a render (it did not run to the end) and a couple of screenshots. I have one big area light on the ceiling of the interior space. Not sure if the settings are correct.

Edson

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awaddington
Total Posts: 390

What are your glass material settings (and is the glass material applied to both sides of your window faces)

eddiemafa
Total Posts: 8

Here you have it. And yes, it is applied to both sides of the material.

Image Attachments
Screenshot_2019-04-09_13.44_.36_.png
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awaddington
Total Posts: 390

Ok, this looks like the same issue another user had recently.

If you look at the preview render in the Shaderlight material window, you will notice the material is nearly opaque and dark.  This is resulting in a mirror-like reflection from the surrounding scene and hiding the interior.

In the *Sketchup* material editor, change the opacity to a value closer to 5 to 8.  Also, unless you intend the windows to be tinted, you do not need a colour for your glass material.  For perfectly clear glass, use white and a very low opacity setting.

eddiemafa
Total Posts: 8

I followed your suggestion but the light is not coming through yet. I even raised the area light strength to 5000. It does not seem to be a glass problem as light is coming through it from a small patio on the left.

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EGIE
Total Posts: 506

Hi! new here or not - no “dumb” question at all !!  :-)
Even if I do not contribute content to your problem here I would like to make you a compliment for your care in detail. For example I admire that you care about that your steel beam corresponds perfectly with your chosen stone texture. This detail alone is everything but not “dump” :-)

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eddiemafa
Total Posts: 8
EGIE - Apr 10, 2019 08:30am

Hi! new here or not - no “dumb” question at all !!  :-)
Even if I do not contribute content to your problem here I would like to make you a compliment for your care in detail. For example I admire that you care about that your steel beam corresponds perfectly with your chosen stone texture. This detail alone is everything but not “dump” :-)

Thanks! It so happens that I am an architect who practices and teaches architectural design. Thus my models tend to be exactly as the building would be if and when built, sometimes even excessively so. I also know that well detailed models contribute to good renders.
Best regards.

kfoojones
Total Posts: 279

Hello Edson,

If you are able to share your model with us at Shaderlight, we could take a look and see if we can identify the problem. You can email the model (or a link to a Dropbox or similar download, if it’s too large) to support@artvps.com.

If you are unable to send the model, the next thing I would suggest that you check is whether there are any accidental ‘double’ faces in the windows – if the glass face (or a component that they’re in) got accidentally duplicated, there would be two panes of glass on top of each other, which can cause rays to get ‘trapped’ between them.

Next, check that your area lights are positioned definitely below the ceiling face – if they’re in the same plane, the ceiling may stop light from getting into the room. Moving the area light down by a couple of millimetres may solve the problem.

Regards,
Shaderlight support

eddiemafa
Total Posts: 8

No problem. Link to download the model being sent by email.

awaddington
Total Posts: 390

Hi Edson,

I haven’t abandoned you. I’m just fighting a few deadlines so I had to take a pause in the conversation. 

Shaderlight Support’s concern of geometry duplication also came to mind when I was thinking about your last post.

Another test you might try is to run another render in artificial lights only using a manual exposure of 5.5 to 6 to see if any light is coming through that window from the interior. You may also try putting an object immediately behind the window to see if it is visible. If not, then there is definitely an issue with either the light source or something blocking the view through the window.

Your render challenged me in that there was nothing through the windows and no reflection on the windows.  I would expect to see either a reflection or something albeit dim) inside.

You are in good hands with the support team though. I’m sure you will have a simple answer soon.

Also - further to EGIE’s post, great model!

Andrew


kfoojones
Total Posts: 279

Hi Edson,

Thank you for sending your model over. I’ve had a look and I think there are a couple of things you can do to get the interior to show up. In the model we received, I couldn’t find the area light in the room, and the glass materials still had quite a dark colour assigned to them.

First, I changed the glass materials to be white, which results in a render similar to the first one you attached here – showing a strong reflection of the exterior. Since you have modelled the windows with thickness (using two parallel faces to represent both sides of the pane of glass), I also changed the Shaderlight material type to Transparent - Solid Glass. It shouldn’t make much difference in this case, but it will give the correct refraction of light passing through the glass, versus using Thin Glass. BTW, I noticed that you used a different material on the inside surface of the glass to the outside (Material19 and Material20). In general, I would recommend using a single material for both faces so that they can’t get out of sync with each other and produce non-physical results.

To make the interior visible, it needs to be brighter than the reflections, so a very strong light source is needed. I added an area light with an intensity of 1,000,000 candela, which gives the result attached below. You can tweak the intensity of the light to adjust the relative brightness of the interior and exterior. Note that this is no longer a truly photorealistic render, since the brightness of the area light is not realistic, but it is a useful technique for showing interiors and exteriors in the same render.

I hope that helps,
Shaderlight support

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eddiemafa
Total Posts: 8

Thank you, guys. As soon as I have time I will go back to working on this render and wiil report here.

I would like to mention the friendly, fast and comprehensive help one gets from this forum. Shaderlight users are lucky to have this kind of support.

awaddington
Total Posts: 390
eddiemafa - Apr 09, 2019 03:00pm

I apologize for the coming dumb questions…

If nothing else…even if you don’t find an answer… this thread should at least validate the fact that you didn’t ask a “dumb question”.  ;-)