chroma key
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- senseg
any ideas how to cut green background like in video editing, but in photoshop?
- feel0
color range should work
- juhls0
You could try the background eraser and change the tolerance depending on what you need to do. Getting rid of a green screen in Photoshop is a pain in the ass.
- version30
shift click
- graham4140
^ lol thats so funny but its lightweight and low key true
- fryday0
Best bet is to probably mask it out using channels.
- 2ndcrack0
Use Calculations:
First create a new alpha channel with red channel as source 1, blue as source 2, blending mode 'lighten'.
Next create a further new channel using Alpha 1 (which you just created) as source 1, green as source 2, blending mode 'subtract'.
This gives an alpha channel based on the green content but will need scaling using the curves command to full black/white values.
- 2ndcrack0
You can create an action for the calculations commands.
Once you've scaled the greenscreen alpha channel for one image any others from the same shoot/sequence should need roughly the same scaling so this can be added to the action also if needed.
- felizfeliz0
to tidy up jaggedly edges after removing your green background:
Layers>Matting>Defringe...
works wonders.
- 2ndcrack0
The calculations method should remove all traces of green around the fringe even partial values in edge pixels, but I might have a tidy-up action I use as well at some point, I'll try and find it.
- harlequino0
That's a new one on me, 2ndcrack. Giving that a try today, wish I knew about that method a week ago when I really needed it.
- 2ndcrack0
This book explains how to do this properly:
http://www.amazon.co.uk/Digital-…
As well as the basic matte method above there is a further despill operation for Photoshop described in the accompanying production excercises, look for excersise 4-4 How to Despill a Greenscreen in Photoshop:
- 2ndcrack0
herlequino - I had to do some work with stills from a greenscreen shoot last year, I wasn't completely clear on how this worked until reading the book.
If you try the despill excercise I just posted you'll probably think it's some kind of digital voodoo like I did, the book has completely changed the way I approach creating mattes for stills now, it's got far more than greenscreen compositing in it it's worth it's price twice over at least.
- harlequino0
Oh I hear that, and it feels like a totally sound way to do it. I've done plenty of matte pulling in AE, but it always seems an odd mystery in PS. This method really echoes the compositing process I would normally use. Great stuff, and it'd be sweet to not have to rely on detailed pen tooling every time I run into this situation.