[JPMays]

I am trying to achieve a similar lighting effect as in the above photograph. I'm having trouble getting a dusky sky with a bright building (exterior & interior). Does anyone have any general tips on how create this in MR?

[brodie_geers]

To me the sky looks entirely photoshopped based on the uniform gradient and the white 'halo' around the building.

For lighting I'd say an HDR with a warm evening glow perhaps? The lighting is very uniform so I'd think that would work well.

And maybe a photographer could chime in but the foreground lighting looks a little odd to me (not necessarily in a bad way). It's almost as if there's a flash coming from the camera area or something.

-Brodie

[Maximus3D]

I have to agree that the sky is added in post, they usually are replaced in architectual shots like this one. This example is pretty poorly done to be honest.
But what i guess based on the lighting in the front of the building is that it 'could' be shot with existing lighting but just a long exposure to make it bright enough. Or they could have used a big two meter silver flash reflector to illuminate the building but i have some doubts about that.

/ Magnus

[JPMays]

Yeah, I've been thinking I'll need to photoshop the sky, can't seem to get it quite right with Maxwell skies. My main problem is lighting my model. right now I have some decorative fixtures lighting the building, but also some hidden giant blocks of emitters to give an ambient light. Do I just need to pack the building with lights?

[brodie_geers]

For the most part, the closer your lighting is to reality, the closer your result will be to reality. If you just fill the building with large invisible emitters you'll have issues with regards to that. Your starting point, then, should be to have place a bunch of lights with reasonable wattages in reasonable locations about the building close to where they'd be in reality.

-Brodie

[JPMays]

For the most part, the closer your lighting is to reality, the closer your result will be to reality.

I wish I could believe this, but I have not experienced my desired result with lighting as it would be in reality. It's quite probable this is my error, however. Are there any tutorials you would recommend fro achieving accurate lighting? This is my biggest MR weakness.

Here is my first shot at the image:



I have trouble with the actual sources being super bright, yet not creating much ambient light on nearby surfaces. The interior continues to be dark.

[Half Life]

That sounds like a scale issue -- make sure you are working at 1:1 real world scale for realistic lighting effects.

Also the geometry matters -- if the emitters are grouped as 1 object they could be considered 1 piece of geometry and the total surface area would need to be considered for the emitter material power. Using Multilight can help you quickly test for those types of issues.

Best,
Jason.

[brodie_geers]

Maxwell doesn't fake any lighting so if it seems like the light is bright but isn't creating ambient light there's a physical issue. Here are some possibilities.

1. scene scale: if your living room is scaled to 120'x120' instead of 12'x12' the light look like it's falling off too quickly.

2. gamma: make sure your gamma is between 1.8 and 2.2 depending on your computer. I think 2.2 is pretty much default now.

3. light power: a small emitter at 100w is good but if you've got a large planer emitter at 100w it'll be very dim. make sure your emitters have a realistic power rating

4. camera exposure value: in tandem with realistic lighting make sure your camera settings are realistic. check this chart http://en.wikipedia.org/wiki/Exposure_value

-brodie

[JPMays]

I might post this to the Mr for SU board, but I'll try here first: how do you adjust the temperature of emitters using the SU plugin? All I can find is color by RGB. Trying to create realistic emitters but not sure how RGB matches up with Kelvin.

I am at real world scale, gamma at 2.2 (default). Have adjusted my emitters based on the size of the object. F-stop 5.6, ISO @ 800.

[Half Life]

That has been added to the new 2.6.10 plugin -- so you should see that when setting up an emitter material once you have the new version installed.

What is the EV? and the Focal Length of the camera?

Best,
Jason.

[JPMays]

Sweet, I didn't realize there was a plugin update too. I like it!

EV is 14, can't figure out how to find the focal length. SU will only show me field of view right now (45 deg) when I use the Zoom tool.

[Half Life]

EV of 14 is way too high -- you will likely want to set that to at least 9-10 for the effect you want... make sure you read all the way through this link: http://en.wikipedia.org/wiki/Exposure_value particularly the "Tabulated exposure values" table.

You will also want an alpha channel render for post purposes.

The field of view can accept input in either deg or mm -- setting it in mm is what you want to control the focal length since it will make more sense photographically.

Best,
Jason.

[JPMays]

I figured if I typed in something in (mm) it would change it, but I can't figure out how to display what my current FL is. Do you know how to do that?

[Half Life]

Try dropping this into the Ruby Console

Code: Select all

Sketchup.send_action(10624)

Then you can just use a calculator like this: http://kmp.bdimitrov.de/technology/fov.html to convert the values.

Best,
Jason.

[brodie_geers]

Once you edit your focal length to be something like 35mm in SU, from then on it should display in mm. Are you saying that isn't the case?

-Brodie