Hi all,

I have not traditionally been one for using backgrounds when rendering. However, when I do, I have always found it difficult to match a set of lights so as to make the scene look realistic.

Was wondering if anyone has any suggestions on how to achieve this match ?

Thanks,
Andrew

The Mk 1 eyeball

look at where the shadows fall and where the illumination appears to come from then set the lights to match

thanks, but what is the "Mk 1 eyeball" ?

it's your own eye...;)It's a military-type name for it...;)

I use backgrounds all the time...I usually try to remember the intensity, color, and direction of the lights (I usually use Bryce), and when time comes, to use the Poser lights with roughly the same settings.

Also, in some cases, I'll try to use fainter lights as 'reflected' light; for example, maybe sort of a grayish light coming off metal, or brownish off wood, and blueish (is that a word?...;) off the sky, depending on the scene.

Hope that helps.

I'm ambivalent about it myself. I can't decide whether it's easier to match a light set to a background that has a very obvious light source and some shadows (from trees, for example) or to a background for which the light source is kind of obscure.

Just as important as matching light and shadows, though, is getting the gamma and resolution equivalent on both the background and render. Not much worse than seeing a high res but washed out render pasted on top of a dark low res background (or vice versa). A shadow mismatch might be apparent after a few moments of contemplation, but a gamma or resolution mismatch jumps right out of the screen at you.

Depending on your Poser version, there is also IBL and IDL to match global illumination to the background scene.

my vote would be to use bill's envdome with an hdri.  the background is the lite source.  somewhat advanced topic, e.g. how to:

• get a nice hi-res hdri
• use an hdri in poser
• use IDL (GI) in poser

trying to match the poser directional lites to a background is hopeless IMVHO.  this may be why we saw lite sets with dozens of lites in them sevl. yrs ago.

Sorry MN but how exactly is that going to help you match a background ?  Bills dome is undoubtedly an excellent bit of kit but won't help in this case unless you have a hi-res HDRI of the background image which won't always be the case.

Take this image by 2121 for e.g - he's done an excellent job of matching the lighting from what is a particularly tricky background image (I know - it's mine and is heavily post processed)

The envirodome wouldn't be much use in that case

Does BB's dome allow you to have an image background ?

Yes it does, however you need to use a wide focal length to maintain sharpness.

There is a method of using "HDRShop 1" + the plugin "Lightgen" to generate a Mel script that creates and arranges 3d lights based on Lightprobe image data.  

Stefan Werner wrote a Poser Python script that converted the Mel script into something that Poser 5 could use.

If you feeling really adventurous,  you could use BB's Environment Sphere as a background, then his GenIBL - IBL Generator to create the Lightprobe,  then HDRShop+Lightgen to generate the Mel script, the Stefan's script to make the Poser light rig....   Whew!!!

Or, you could eye-ball it  :)

BagginsBill

HDRShop

Lightgen

Stefan Werner

Later

reason it's difficult matching lighting to bg pic: no info avail. on foreground. but it's equally difficult trying to get 19200X9600 hdri AFAIK.