[caryjames]

Hi Everyone: When using Maxwell to render jewellery are people using emitters to light the scene or are you just turning on the sky dome feature? Thanks in advance for the input!!!
Cary

[ricardo]

HDR maps. If you are willing to spend some bucks for a quick start check this:

http://www.doschdesign.com/products/hdr ... ts_V2.html

There is also some free stuff available. Usually the HDR map and some emitters to lite up some gems. Keep far away from the sky dome and physical sky unless you know exctly what you are looking for/doing.

Ricardo

[hyltom]

I also recommend you to use HDR (specially those: http://www.hdri-studio.com/) for all kind of studio setup scene or if you don't want or can't afford to buy some pre made, so make your own LDR. The result will be similar, it's pretty easy to do and will not take long. Basically it just a picture with a black background and some white square like this:

[ivox3]

Hugo, .....I'm curious as to how you derive the shapes for the LDR's ....?

What I mean, .. is there a methodology to the shapes in terms of reflection effects generated ? ....been meaning to ask you this for awhile.

[ivox3]

Cary ..... yeah, ... stay away from the dome/sun/phys.sky .... The primary light is going to be emitters and the 'fill' / reflectons, ....definitely an HDR.

Remember, ...the smaller the emitter, ..the better your caustics are going to be -- at least, more defined.

I'd also stay away (personal taste) from the warm emitter presets and use the 'colder' or bluer spectrum presets.

[hyltom]

By derive i suppose you mean deformed...This is not easy to explain with my poor english. So i will tell you how i have done to get this result step by step...just give me some time to prepare everything.

[ivox3]

How about we say, ........'arrived' , ......how you arrived at those particular patterns/shapes ... ?

[hyltom]

How to build your own LDR?

1. In Rhino, build a basic photographic studio...so basic that in fact it's a cube open on one side.


2. Put a sphere in the middle of the studio. The center of the sphere should be at the same high than the ground of your studio. So actually you just can see half sphere.


3. Put the camera above the sphere, pointing toward the sphere.


4. Set the different materials.
For this tutorial, i have choosen this color:
Sphere=chrome
Ground=beige
Left wall=red
Right wall=green
Ceiling=yellow


5.Render the scene using maxwell sky dome.
After few minute, you get this:


6.In HDRShop, open the maxwell rendering and make a panoramic transformation from a mirrored ball format to a latitude/longitude format with some arbitrary rotation (X=90, Y=0, Z=180). Then save the new image in a low dynamic range format.


7.In Photoshop, slightly modified the HRDShop image to get the horizon at equal distance from the top and the bottom and make an horizontal flip to put back the red wall on the left.


As you can see Ivox3, the ceiling shape in deformed simply because we come from a spherical environment that we change to rectangular.

This image is the base of your future LDR. As i said previously, a LDR of a photographic studio is mainly composed of black and white surface.
Use this image as reference for the shape and the positioning of the different element. For example if you want a light coming from the right side, just change the picture as follow.


Remember, the background should be totally black. In this exemple i want you to see where to put the light so the background is little bit visible.

[ivox3]

I can see ... It all makes sense now, ... I knew there was a method.

Thanks for taking the time Hugo ...... quite nice.

[caryjames]

I will have to digest this because at the moment it is a bit like learning a new language-Greek comes to mind ! But I have to say you folks are great, I really appreciate the effort it took to post the reply!
Cary

[ricardo]

Hyltom,

Did you try doing HDR this way? Isn't it possible in 1.5?

Ricardo

[caryjames]

O.k. First off thanks again everyone! And thanks to all for being patient!

I feel that I am missing an important step/concept.

Hyltom are we are creating a pipe that will sit outside the camera's view and will have some holes cut out of it to allow emitters that sit on the outside of the pipe to shine through these holes and create different reflection effects? Is this correct?

Or are we creating a dome that will only allow light to enter the scene from one particular point?

If you had a screen shot of the scene so that I could conceptualize it would be great. If this infringes on your work please don't feel pressure to show your setup, I don't want to be insensitive!

Any clarification would be great. Thanks again everyone!!!!!!!!!!!!!!!!!!!
Cary

[ivox3]

Hi Cary ..

No pipes will be used in the production of this technique. lol.....

The final image created from the scene gets used as an enviornment emitter, ... like an HDR, ..but it's an LDR (low dynamic range) image. The white part of the image is the emitter and the black parts get reflected into the scene.

If you don't understand the usage of an HDR/enviornment emitter, ..let me know and we'll go into that a little ....

Hyltom was just demonstrating how to create the image seen here:


He created it using the method above and that final 2-D image gets turned into an emitter (an MXI file) via mxcl.exe.

If you open mxcl.exe and import an image, ..you'll have the option to save it as an mxi file ---- this file can then be used in any or all of the envrionment slots within the plug-in or Studio. Give it a whirl......

[caryjames]

So does that environment emitter wrap around the object (...like a pipe LOL), or would it just be a flat plane set back from the object you are rendering?

How big would this object be in relation to your jewellery- 2-3 times as big?

So the white part/emitter is on the same plane as the black?

I guess I sort of understand- I just don't understand why you wouldn't just
create your object (that black and white thing) in Rhino and then assign .mxi materials to it-instead of creating that light box with the different colours and chrome sphere and then projecting and editing in photoshop.

What materials would you assign to the black and white thing?- Black plastic and an emitter?

"If you don't understand the usage of an HDR/enviornment emitter, ..let me know and we'll go into that a little ...."
I would love it if you would!!!!

Thanks again for your repsonses-this is a whole new world to me and I am slowly getting the hang of it------I hope!!!
Cary

[lebbeus]

The image gets mapped to the environment channels--so no geometry (like a dome or wrapped plane(pipe)) is needed, thus it should render faster