Week 5 Review Questions

1. What steps would you take to colorize a gray-scale image?
   You could use the Colorize option (and play with the Hue and Saturation) or use the Gamma Correction. I did an experiment using Colorize with a grey scale image.
   
   
   
   The Hue and Saturation started out at 0 and 0. If I increased the Hue to the top of 255 nothing changes. But if I start the hue at 0 and Saturation to the top of 255, the color is RED. I start to inch the Hue up and the color changes from ORANGE, GOLD, YELLOW, YELLOWISH GREEN, GREEN, BLUEISH GREEN, BLUE, DARK BLUE, PURPLE, PINK, and back to DARK RED.
   
   
   This is similar to working with the Gamma Correction (I think). If you start out with a Gray Scale image and Split On RGB Channels, then move each color up to it's maximum, you will get the same as what I did above with Hue and Saturation.
   

   Max RED looks like          
   Max GREEN looks like        
    and finally max Blue       
   Combo Max Colors looks like 
   

   
   
   
2. When you choose Edit | Masks why can you only select from white, black and grays?
   Masks are grayscale images or grayscale channels. A mask can have 256 shades of gray, with WHITE being totally transparent and BLACK is totally opaque. This would mean the shades of gray vary in degrees of transparency accordingly.
   
   
3. What are the steps involved in saving a mask?
   You can save a Mask to Alpha Channel or to Disk. If you save the mask to Alpha Channel it is saved with the image. If you save to Disk then you can re-use the Mask but it is not saved with the image. If you save the Mask to Alpha Channel then the image needs to be saved as a PSP, TIG or TGA. The extention for a Mask saved to disk is .msk
   
   
4. What is a major advantage to using masks with layers (there are several answers possible here)?
   Saving anything to layers allows you more leeway in changing and editing in that you can change a layer without affecting the entire image. With Masks you can create different effects by working on the different layers and this would be impossible without layers. You can also toggle layers on and off when working on the image.
   
   
5. What is the advantage to using Gamma Correction over adjusting the brightness and contrast in an image?
   If a photo has too much of a color, for example my picture of Rummel is very heavy on BLUE. So I reduced the Blue and increased the Red a bit. But then there was a touch too much Green so I lowered that a little bit. Here is the two pictures, the original and the final Gamma Corrected picture.
   
   
   
   NOW that is WAY better!