Extracting a Glass from a Photo

Posted on: November 4th, 2009 2

In one of my “Alpha Channel” vids I mentioned I’d cover this topic. Well, I finally got around to it. Turns out I needed to do this for a real-world situation. I was designing a website for a client and wound up needing to extract a glass from one photo and place it in another photo. Along the way I fell in love with Content Aware Scale, then just as quickly fell out of love. I’m so fickle.

At any rate, I cover the following topics:

  • Color Range
  • Alpha Channels (of course!)
  • Content Aware Scaling (new in CS4)
  • Faking a cast shadow (not a drop shadow)
  • Brushing in opacity using the, er, Brush
  • Faking specular highlights (no, really)
  • Layers, Adjustment Layers, Layer Masks

There’s a lot of useful stuff here. I know it’s sorta long (a little over 40 minutes), but I promise everything I cover is stuff I do everyday in Photoshop. There is nothing esoteric here……just real-world Photoshopping!!

I know some folks have asked me to include the image files I use, but in this case I really can’t as they are stock images that the client purchased.

Please don’t hesitate to post a comment below if you feel inclined.

[flv:http://www.garydatesphotos.com/screencasts/glass.flv 540 405]

arrow for full screen mode
Tags: , ,

2 Responses

  1. Roeland says:

    Looking with great interest to your extracting glass tutorial. Very well done.
    A few remarks/questions:
    – creating the reflection of the stem, isn't it better to not only copy it and turn it upside down, to flip sides. I noticed in the 100% opacity setting, that the right side (black) shows on the left of the reflection.
    – Although you mentioned that the background distortion created by the Content Aware Scaling tool was fine, how would you actually repair this kind of distortions?

    • songworks says:

      As to the reflection, yes, I should've simply used "Flip Vertical" inside the "Free Transform" tool to get the correct orientation. Regarding the artifacts introduced to the background using Content Aware Scaling, there is no easy way to repair it. What I would try is create another copy of that layer immediately above it , blur it (to minimize the artifacting), and then create a Layer Mask. Using a black brush, I would then "paint in" the glasses and table top until it looked convincing……..pretty tedious work. This is the problem with Content Aware Scaling…..which is why I fell out of love with it rather quickly.

Leave a Reply

You must be logged in to post a comment.