Digital Photography - Class 3
Enchancing
- Review Homework
- Check out examples
- Go over proper photo taking techniques
- Workflow for enchancing images
- Global tonal or color correction (too dark, color cast)
- Selective adjustments
- Optimization (resize, sharpening)
- Keep in mind
- Image correction is subjective
- Many ways to achieve the same result
- Ultimately you or the client decides what is "correct"
- My goal is to explain how the tools work
- Tonal Corrections
- Brightness and Contrast
- Brightness and Contrast is a bad way to alter Brightness and Contrast
- Shifts all tones
- Levels
- Quick and easy way to set highlights, shadows, and midtones
- Black and white sliders change hightlights and shadows
- Gamma slider changes midtones
- Output levels alter final output
- Threshold view (option - move mouse), look for "jumps"
- Use option key for auto-reset
- Curves
- Similar to levels but more precise control
- Input/Output are before and after values
- Command click on image to get point for that pixel
- Use arrow keys to nudge points
- Control Tab to cycle through points
- Use option key for auto-reset
- Color Theory
- Additive or Primary Colors
- White light is actually broken down to RGB
- Combining these primary colors creates the entire spectrum
- These primary colors are known as "additive primary"
- Computer monitors and TV create color by this method i.e. adding
- Subtractive Color
- Colors on a printed page don't emit light, the page reflects light
- Pigments such as inks "absorb" light
- Combining two of the three primary colors creates "secondary colors"
(CMY)
- These colors are known as "substractive primary"
- If you add maximum of cyan, magenta, and yellow you get black, in
theory
- Really muddy brown
- Thus Black is added to create (CMYK)
- The color
wheel
- Color Corrections
- Histogram
- Able to see Luminosity compared to RGB
- Can also see channels in color
- Info Palette
- Able to see RGB values
- Gives before and after readings
- Can compare to CMYK and check for gamut warnings
- First readout RGB, Second readout CMYK, pixels
- Use color sampler to monitor changes at critical area
- Able to sample by point, 3x3 or 5x5
- Levels
- Not the best of color corrections
- Useful for image-evaluation though
- If image has no color problem but needs a bit of lightening
- Auto Levels, Auto Contrast, and Auto Color
- Of the three "Auto Color" works the best
- You can access these auto features via Levels or Curves
- Click Options while in Levels
- Select "Find Dark and Light Colors"
- Check "Snap Neutral Midtones"
- Set clipping percentages to 0.0 to 0.05
- Adjust midtone color when necessary
- Curves
- May be the most useful tool in Photoshop for tone and color corrections
- Takes some time to master
- Eye droppers in both Curves and Levels tend to be useful for CMYK output
- Moving down will decrease a color, up increase it
- Command click to find a color
- Hue/Saturation
- Great for working on a defined range of colors
- Able to fine tune a range
- Levels and Curves work better with global changes
- Replace Color
- Similar to Hue/Saturation however the range is more precise
- Useful for specific or local changes
- May have blending problems with very different colors
- Photo Filters
- Similar to real photo filters on cameras
- Selective Color and Channel Mixer
- Used primarly on CMYK files
- Color Balance
- Color Balance command does not get used much
- Curves achieve the same results
- Not as much control as Curves though
- Variations
- Cool tool to learn color theory but rather crude
- Not used very much
- Repairing an image
- Clone stamp
- Repeats part of the image elsewhere
- Option Click to establish a point
- Has problems with subtle tones
- Healing Brush
- Works like the Clone Stamp tool
- Does an amazing job blending from sample point to target
- Don't even have to match color and lightness just texture
- Make an editing layer
- Patch Tool
- Functions similar to Healing Brush though uses selection instead of
a brush
- Hold down option key for straight lines
- Red eye
- Select eye with oval marquee with a little feathering
- Copy selection to new layer (Command - J)
- Using Hue/Saturation start with Hue +40 brown eyes, Hue -120 blue
eyes
- Set saturation to -75 and lightness to -50
- You can save this setting for future repairing
- Shadow and Highlights
- No adjustment layer so first copy background layer
- Amount is like a volume control
- Tonal Width how far to the shadow or highlight to go
- Radius has to due with surrounding luminance (set to about half of target)
- Add layer mask (hide all) and paint
- Cropping to a size and resolution
- Change interpolation setting to "Sharper"
- Be careful of interpolation
- Try to crop down not up in resolution
- Use arrow keys to move selection
- Use ESC or "No Way" symbol on options toolbar to cancel
- Can also make your own crop settings
- Using crop tool to add more canvas area
- Position your window so you can see the canvas outside of the image
- Use the crop tool to select your image plus what you want to add
- Straightening Crooked Photos
- Select measurement tool
- Find a straight line such as the horizon
- Select "Rotate Canvas -> Arbiturary"
- The proper measurment should be selected along with rotation
- Crop rotated picture