Difference between revisions of "Visualizing Microbial Seascapes - Intro to Photoshop"

Revision as of 14:51, 11 May 2016

Scanning

• See step by step instructions: Scanning from a Macintosh
• Recommended scanning resolution for Zoetrope strips to Quicktime = 150dpi, for print = 300-600 dpi

Photoshop interface and navigating an image

1. Opening a file File > Open and navigate to your file. Never open a file over the network (if your file is on Orca, first copy it to your local hard drive).
2. Intro to basics Photoshop interface elements
3. navigating an image
   • Zoom: Cmd +/-
   • Hand tool: Space Bar (used to move around an image)

Image size and resolution

1. What is a pixel? Zoom all the way in on your image.
2. What are the dimensions of your image?
   • Go to Image > image Size to see the overall size in pixels of your image
   • Resizing photos for various usages including: Web, email attachment, and print
3. What is the resolution or pixel density of your image? Why does it matter? See more in discussion depth on resolution.
4. Cropping - using the crop tool to remove portions of the image outside of the crop selection
   • You can set the image size to crop to in the properties bar i.e. 400 px (remember the px)

Saving your work

File > Save as. Choose Photoshop as the file format. This will create a uncompressed Photoshop native image file format (.psd). It's a good idea to keep an uncompressed copy of your images.

Working with Layers

• Create new layers
• Hiding and linking layers
• Copying between layers and duplicating layers
• Adjustment layers - try adding a Levels adjustment to improve the contrast of your scanned image

Working with selections

• intro to selection tools: marquee, lasso, magic wand etc.
• Extract an object from the background
• adjusting selections
• copying selections to another layer

Batch Processing Groups of Images

Animated GIFs

Saving for web

1. Saving for web: File > Save for Web & Devices
   • Choose the highest quality with the best (smallest) file size.