Syllabus | Notes Index

Lesson 6

Final Project - Quiz

Want to switch to Black and White? Optimizing Grayscale Images:

How should we look at our images: show different settings in the tools palette---show a grey square on both light and black (which is lighter?)

Brightness and Contrast(show): why is this not good enough
Flat, Dark, Blown out Detail, Lack of Detail in the Shadows

Levels: Review of the histogram

The outer sliders are adjusting our contrast, the inner slider is adjusting our brightness and contrast.

Determining the darkest shade of grey in the image (vertical from far left of histogram), as well as the lightest shade of grey----simply a reflection of the most prevalent shades of grey in your image.

Evaluating contrast: what our eye sees, what the monitor sees, what printed material sees

Adjusting sliders in the levels: Move the right one, you are forcing any shade that appears directly below it and anything birghter than it to white.

Threshold mode (show what threshold is Iamge>Adjust>Threshold: Allows you to see what part of the image is turning black or white (if there is too much becoming black or white you are sacrificing detail) ---hold down the option key

Three things that might cause an image to have large areas of white or black
1. your scanner or camera isn't capable of capturing good shadow or lightness detail

2. The image didn't have any details in the highlights or shadows to begin with (maybe it is underexposed or overexposed)

3. The image has already been adjusted in Photoshop

Once you have applied an adjustment you can go in and see the revised histogram by going into Levels again. You will see spaces in the histogram, the spaces represent shades of gray that are missing from the image (so by making the image more contrasty by pulling out our white and black points (show in b/c), we are sacrficing middletones or shades of grey.

Spikes on the end of the histogram show very contrasty images (show)

An image that has a lot of peaks and valleys is an image with noise (show)

Look below the middle slider, what it is doing is making the grey that is directly underneath it into middle gray and adjusting all other greys accordingly

(ask a printing company what settings to use---always get a color proof)

For the rest of class take one of the images that you shot for homework and adjust it using what we have learned.

Show printouts.