Replace specific color range

[Andy289]

I have a set of coins images that are made on a rugged green background and I would like to get the coin on a transparent background. I tried some things, as a newbie, and I got pretty good results but the edge of coin isn't very good as I replace the old green background. I am looking to learn how to make it better and without many headaches because I have to edit hundreds of images like that.

Here is an example of image

and this is what I got after 15 minutes of work on image


I would like to know if I can do it better and with less effort, as I mention, I have to edit hundreds of images like this one. Thank you.

 

[Inkz]

Try this...

Grab a hard brush the same size as the coin. On a layer above the coin image, click once and cover the coin image....



Then Alt and right click on the brush layer to select the circle.



Now click on the coin layer, then press Ctrl+J

Now go to refine edges...



Here's what I got with the above.



Hope this helps.

 

[Andy289]

Nice way to do it. I have to work a little with refine edge tool to see exactly how it's work because my edges looks ugly compared with yours.

 

[Inkz]

So long as you feather and shift edges, you should be fine.

 

[Tom Mann]

There are many, many ways one can achieve a nice smooth edge to a "cut-out" task. Inkz's approach of using the "Refine Edge" tool is an excellent suggestion. I would just add a few comments.

1. You should never, ever attempt to do a cut-out on such a small image. At minimum, you should have at least 2000 pixels in both directions, even if the image will eventually be reproduced at smaller size, say, on a web page.

2. For something like a circular object with a smooth boundary, I suggest you adjust the "smooth edges" slider in "Refine Edges" to several tens of pixels. Any lower and you probably won't see much effect. Any higher and you risk incorrectly deforming the correct but not quite circular shape into an (incorrect) perfect circle.

3. This is purely a personal preference, but I would start the cutout process with a quick select tool of approximately the correct size instead of using the black paintbrush.

Here's an example:

 

[Andy289]

Thank you guys for advices. Both ideas works pretty good to get the desired result. For some coins it's pretty quick to do it, others can be more difficult because of strange shapes (they are not just round) or other images have a thin shadow that make my selection difficult and then the refined edge a little bit ugly. But overall I can do what I need, with less or more effort so many thanks. If anyone have any other tips or ideas don't be shy to say your suggestions.