How To Hide background image but still keep its color and light effect?

hello , i am using Blender Render, i would like to know are there any way i can Hide background image from the camera but still keep its color and light effect? ( must use Blender Render) thanks!!!1:spin::confused::frowning:

Render properties -> shading -> alpha: transparent.

You can also use compositing-nodes to extract separate ā€œchannelsā€ of information from the render and re-combine them in other ways to produce the final output.

But Iā€™m not quite sure what you mean by ā€œcolor and light effectā€ from a background image. Perhaps you are talking about the need for lighting that creates spills of light, of a certain color, that plausibly would be coming from the background if that background actually were ā€œa source of light.ā€

hello, the object i want to hide is a plane at the back of some metal weapon, so even i change alpha: transparent, it is still there.:spin:

it is one of the color sources, maybe its also a light sources, it makes the object color more brighter and shining. ( the object i want to hide is a plane at the back of some metal weapons)

Use Mix shader to mix your original shader and transparent shader. As a mix factor use the camera ray output from Light Path node. This way all the rays that directly hit the object will see object as transparent, but all the reflections and bounce light it produces will still be there.

Heā€™s using Blender Render, thereā€™s no shaders to mix.

One way to hide it is to put the object on another scene layer and not include that layer in the render layer. It will render but wonā€™t be included in the image.

Oops, that slipped my view. In this case do what JA12 suggests.

hi ja12, can you tell me how to do that ? i can not find the scene layer and render layer, i know how to move object from one layer to another by press M. thanks

Nope. Maybe someone else could.