Hi,
I wasn’t sure how to correctly word my question so I hope it makes sense. I want to use this background image to be see through the window. What would be correct way to use it , be able to control image brightness and image be visible when rendered?
Thanks,
T
If it’s for a static image, just add it to a plane and put the plane where it needs to be. You can use the HSV/Contrast & brightness nodes etc. to adjust the colour, or add it as an emission shader to control brightness.
Hi Roken,
It does a trick if I use HDRI lighting. Then I have enough light in the room and can seperatly control plane image using several nodes. There is one thing I hope you could help me with. If I put an area light in the window the plane image gets overexposed. I thought light would come in but it would not affect the plane image because it faces opposite direction. Do you know how to over come it by any chance?
Thanks,
T
Probably not the best solution, but try putting a large plane between the light and the background image. Add a material (basic BSDF will do) mixed with a transparent texture and the mix factor set as camera ray. This will stop the light getting through from the area lamp, but still let you see the background plane. Doing this means you probably do need to plug the background in to an emission node, but that will give you control over how bright or dim the background is.
For info - the area lamp in this quick and dirty example is insanely bright.
If you are using a HDRI as well you should move the “blocking” plane as close to the background plane as you can, and scale it accordingly.
(Ignore the image I’ve used - just grabbed one, which happens to be me and my other half more than 40 years ago when we met)
Hey!
It was about the time I was siting on my parents lap 
Look I’ve tried to do like you suggested and for some reason I can’t see through. I thought to add file too just to save your and my time. Hope you don’t mind to look into my set up?
light path .blend (845.7 KB) light path .blend1 (845.7 KB)
Thanks,
T
You have the mix shader as a translucent shader - change it to transparent.
How genius of me! Many thanks ! 
