Chroma Key Backdrop

[photo441]

Has anyone tried using a chromakey green backdrop? I am thinking of buying one. Do the keyed out backgrounds look realistic? Does anyone have any good examples.

Thanks,

JP

[mikesd]

I had one and never had much luck with it. Getting someones hair to look natural after the background transfer was extremely tough and on subjects that were lighter skinned the green would bleed on to their skin. In short a large amount of Photoshop work to end up with a less than natural looking portrait.

Mike

[DaveG]

I'd be more inclined to get a white or a grey background for a close-crop background. The background needs to be removed, that's all, and in TV and movies the green works because that same colour is generally NOT within the subject and that colour is removed globally. A computer is set to "see" that colour green and to remove it wherever it exists inside the whole shot. That provided a little fun back in the blue Chroma-Key days when you'd see holes in the subject. I especially remember a TV ad for a regional airline that had a nice stock shot of an aircraft in flight while a flight attendent-actress in the foreground did a voice over. The problem was that you could see through her jacket crest to the background and there was part of the jet flying where some of her bits were supposed to be.

With close-cropping - at least the way I do it - I'd use the magic wand and remove the background from the outside.

Now green would work well for the close crop the way I do it, and any monochromatic colour would too. The problem that I have with the green is that is has no other purpose. I could use the white for other things like passport photos or high key shots. A grey backdrop can be used for just about anything. And both of those backdrops could be gelled and the colour could then be anything, including green.

I'd also be a little concerned with a colour cast on the subject. The last thing I'd want - even with RAW - is a little green showing up in the subjects face or hair, caused by reflections off of the backdrop.

[chris.bailey]

I sometimes use a ChromaGreen and it works well as long as not too much light falls on the background. I use Select>Colour Range to then lift the portrait from the background.

[davepgh1]

I have a Photoshop plug in "Primatte2" it is designed to mask chromakey colors or any single color. Even with the software it takes practice to get it right. You can have spill over problems, you must have the lighting right, it does remove the color globally as pointed out above, and it does have extensions to deal with the above problems.

The effect is not bad; I use four lights, two on the subject, one on the background, and a hair light to provide separation from the background. I find it better to back the chromakey farther away than normal, that way you don't have as much spill over but it requires a larger background. Full length shots require a false floor to give the subject a foundation so they don’t appear to be floating.

Bottom line, I like it now that I have it, but if I had it to do over a grey, white, and maybe blue (painted?) background would be a better and cheaper investment. Think about the volume you have to work with from a single shoot. I have continued to add backgrounds to my collection.