[1STLITE]

Hey all. I was wondering if anyone can tell me, what is the process, step-by-step, for background replacement with a chroma key background, either blue or green? I am using Photoshop CS. Thanks for any help here.

Dawn

[pjanak]

In Photoshop there is no need for the "chromo-key process". Well sometimes there is. If the image has lots of fine detail you want to keep. Such as stray hairs. It can be done via the "Ultimatte" plugin". But if say for example you have a guy standing in front of a chromo green or blue background. And you have another image you want to instert into the background. All you need to do is magic want the area you want to replace. In this case the green or blue background. Then copy the replacement image into the selection area. Having a solid braground color makes selecting very easy. But you dont need a solid color background to select everything but your main subject. You would use the lasso in that case.

Pete Janak

[Gary Richardson]

Hi Dawn,

Are you saying that you have some images with a Chroma Key background, or that you want to create some.

If the former, the easiest way to extract from the background is to use one of the channels to create a mask. (The fact that the chroma key background is blue or green means that you will have a channel with good image/background seperation, making this an easy process).

If you need further info on this process, just ask.

[1STLITE]

I guess maybe I am confused. I know how to replace a background in photoshop, but I guess I thought there was some easier way to do that if the photo had a chroma key background. You know, other than the magic wand to select the background. Am I just lost or misled? lol

Dawn

[Cameraken]

Hi Dawn

The ChromaBlue and ChromaGreen backgrounds are just normal backgrounds But there colours have been specially chosen because they are two colours are not seen very often in real life. This means that that it should be very easy to select these colours without selecting any other part of the image.
These backgrounds should be evenly illuminated to make them easier to select.
They are also used in video for the same purpose.
You still have to select the mask in the normal way. So if you normally use the magic wand to make your selections then you still do it the same way But with very little chance of selecting some parts of the foreground.

Ken