[caustics]

Hi all,

sorry in advance if I asking a very dumb question here ... I purchased MW yesterday and still are a total newbie to it.

The following happens. I build up a simple scene with library objects: a sphere, a cube and a plane. The sphere becomes an emitter. I choose "Compact fluorescent 9W cold" the remaining objects stay with the default material.

The objects remain at the default sizes as imported from the MW library, except the plane which is scaled 4x bigger to be able to catch the shadow of the cube. The sphere is positioned 4 grid cells diagonally in front of the cube.

Environment type: NONE

Hit FIRE ... the preview remains dark,

adjust to 90W ...

hit FIRE ... the sphere starts to become slightly brighter than the surrounding black

adjust to 900W ...

hit FIRE ... becoming somewhat brighter ... still total darkness surrounding

...

by 900,000 W the scene becomes similiar of what I would expect to get with the 9W emitter.

What's going wrong here? Any clue?

Thanks in advance.

Kindest regards,

[jojojoj]

try to check your scene's scale and units, might be that you're working in mm for example and mxw takes it for meters, so power obviously won't be sufficient....

[David Solito]

Welcome caustic.

Did you create a camera?
Did you check your shutter speed in the camera tab?
For emitters always use a low poly object.

Can you post your settings?

[caustics]

Hi Jojojoj,

thanks for the reply ...

I was thinking in that direction too but did not find any setting for that.

I am in MW Studio and the object parameters don't show any size information just the transformation parameters. And for my scene scale is 1.0. The global scale of the import options in the preference pane is set to 1.0 too.

This is really somewhat crazy.

Regards.

try to check your scene's scale and units, might be that you're working in mm for example and mxw takes it for meters, so power obviously won't be sufficient....

[David Solito]

Tips:
There is also a connexion between the size of the emitter and his powerness.
Imagine a plane of 1m x 1m with an emitter material of 9 w.
Now imagine that plane with a size of 10m x 10m, it will obviously emit 9w but it will be diffused from the all surface.

You now maxwell is workin like a real camera. In these conditions, you need to increase your ISO and reduce wour shutter speed...

Try ISO 1200 with a shutter speed of 1 (1/1 second) it will works.

David

[Half Life]

1) Interior lighting would need a low camera EV (5-8 range).
2) No walls to bounce the light means alot of it is escaping into nothingness.
3) Spherical shape will emit light in all directions instead of towards the cube you are trying to light.
4) Sphere is 1m in diameter and there are only 9 watts is being diffused over a huge emitter surface.
5) Most likely your 4 grids mean it is 4m away from the cube.

Real world lights of that power have reflectors and fixtures and tend to be used within enclosed spaces fairly close the objects they are intended to light... welcome BTW

Best,
Jason.

[caustics]

Hi guys!

I am very grateful for your patience and helpful hints.

You were all right about my bloody mistakes ... 1/500 SS + ISO 100 what a fool I am

As I remember from my pre-digicam camera experiences, ISO 400 @ 1/125~250s f 2~5 should be possible to light and render in MW if it acts like a real camera.

I just can't figure out where I adjust the measurement units of the scene in MW Studio, any clue?

BTW: the scene I pretend to lighten is 0,5m x 0,5m in real world measurements, so a 9W light source should be more than sufficient to accomplish this.

Regards.

[Half Life]

The grid tells you what size it is in the viewport and you can use it in the orthographic views as well to measure your objects/scale... for that matter you can specify a particular grid size in the preferences.

I'm going by your setting in the first posts and the primitives come in at 1m by default... if you have a particular real-world scale scene you are having difficulties with perhaps it would best to post a link to it so we could see what the issue is -- chances are it is something simple.

For camera setting it's best to just lock the exposure and use EV numbers to automatically set the values -- less room for error there.

Best,
Jason.

[David Solito]

the same scene inside a box > point 2 of Half Life

[Half Life]

Hey David, watch out for the small focal length -- your scene is looking darker than it really is due to really strong vignetting.

Best,
Jason.

[caustics]

It's definitely a scaling issue ...

in my viewport it says Grid 0.5 (suppose this is to be meters). If this is the case, my objects are about 10 times larger than they should be.

Just to show what I am working at ... here are some images.

Screenshot:


Render:


Regards.

[David Solito]

Hey David, watch out for the small focal length -- your scene is looking darker than it really is due to really strong vignetting.

Best,
Jason.

thank you Jason! I didn't knew that relationship...

[caustics]

While rendering out to SL 14 ...

I am still trying to get my scene into the right scale. Isn't there a way to do this more accurately? Let's say, I know that the BB of the kitchen sink should be 0,5m by 0,5m. Actually it shows a bounding box of 0,73 x 0,19 x 0,73. What I am doing now is to scale it down visually and bring it into conformity with the grid. Let's say I want it do numerically.

In this context ... is it correct, that a group of objects gets a bounding box of 0 x 0 x 0? In this case, when selected together the children gives a BB of 0,73 x 0,19 x 0,73 ... very strange.

I thought, well group them together and scale the whole group down, this would work too.

BTW: anyone needs a shader that makes water look like mercury?

Regards.

[Half Life]

What I usually do for odd shaped objects (trees, people etc) that need to be scaled is import in something simple at the correct size (like a primitive cube, which can be scaled) and then scale the group by eye to match roughly.

Transformations in Studio unfortunately do not tell you much about the size of the object if you don't know precisely what it is beforehand -- which is why knowing primitives come in at 1m is useful.

Best,
Jason.

[David Solito]

You can use absolute grid in your pref. It's easier for me to rescale object with a fixed reference.