Digital Class Notes Meeting 16

Meeting 16

Fidarsi e' bene, non fidarsi e' meglio

Topics: Anti-aliasing, Stroking the edges of a selection, Actions and Batch Automation, Intro to digital camera topics.

Anti-aliasing edges in Photoshop
Open the file called anti-aliased.tif in Exercises 1 and examine the edges of the two words. One is anti-aliased and the other is not.

Rules of thumb about anti-alias:

anti-alias on: when selecting parts of photographs, when creating type for the web, etc.

anti-alias off: working with 1-bit bitmaps (aka "line art"), anytime no-fringe edges are desired.

Anti-aliasing affects the Type tool and selection area tools (including the Lasso tool, Magic Wand tool, and Marquees of various shapes).

TIP: If you see something on the screen and wish to know if it's anti-aliased or not, take a screen capture (on the Mac, Command-Shift-3) and examine it at higher magnification in Photoshop.

Stroking a Selection Outline

Any selection area (marching ants) can be stroked -- it will work with the Rectangular Selection Tool, the Oval Selection Tool, the Lasso, or even an area selected by the Magic Wand Tool.

In a previous exercise, we stroked a Path using an icon at the bottom of the Paths palette. This has advantages over stroking selections - mostly because you can use any brush available, with whatever settings the brush has available (soft edges, different application modes, brush tip shapes, etc.) However, there are times when only a simple, hard edge stroke is needed, and stroking a selection outline is very quick and easy.

Open JOE.TIF (Exercises 4), and change color mode to RGB.

Draw a marquee just outside the head and upper body with the lasso tool.

Choose an appropriate foreground color for the stroke step. (Light Yellow works OK.)

Edit>Stroke, and choose about 12 pixels. For best results with this picture, choose Outside in the Location part of the dialog box. If you choose Inside, then part of the stroke will obscure Joe.

NOTE: A softer stroke can be created if the selected area is feathered first.

A More Useful Application of the Stroke function:

File>Revert or reopen JOE.TIF

Change color mode to RGB.

Use Lasso Tool to select Joe from the background.

Save the selection as a Channel by clicking on the Channels Tab, and clicking on the Make Channel from Selection icon located at the lower edge of the palette.

Click on the Layers Tab in the Layers palette to leave Channels and to return to the image itself.

Layer>New>Layer via Copy (or type Command-J)

Click on the Background Layer.

Click on the Channels Tab, and drag the newly created channel to the Load Channel as Selection icon located at the bottom of the Channels palette. Marching ants should appear.

Click on the Layers Tab to leave channels.

Select an appropriate foreground color for the stroke.

Choose the menu item Edit, then Stroke. Try 10 or so pixels using a pale foreground color.

Deselect to drop any selections.

Gaussian Blur the background containing the stroke, leaving the top layer untouched.

There should be a "glow" around the figure of Joe.

Done

This technique works best on non-descript backgrounds like that found in the JOE.TIF photo. If there is a pattern or important background, the stroke and blur should be made on a new, blank layer and have its opacity adjusted to blend in with the background texture.

Horizontal or vertical stripes can be made in a picture by stroking selections made using the single row or column selection tools. Using the shift key, you can make multiple horizontal of vertical lines to stroke all at once.

The Actions Palette
The purpose of the Actions Palette is to speed up repetitive tasks. It memorizes a series of steps done by the operator, and can play them back on other images.

You will need to have the Actions palette visible. Choose it from the Window menu. You should see a folder called Default Actions in the Actions palette. This folder contains a number of different actions that are played individually.

Making Actions Work:

To run an action on a single file, open a file, choose the desired action in the Actions palette, and click on the Play button in the Actions palette.
To batch process multiple files in a folder, choose File>Automate>Batch.
To batch process multiple files from a window in Bridge, highlight the file thumbnails you want, then choose Tools>Photoshop>Batch.

Single play
Open Musicians.tif, convert to RGB mode, and run the action named Sepia Toning (Layer) to see how an actions works. Running an action is accomplished by pressing the Play arrow at the bottom of the Actions palette.

Another In-Class Exercise: In the Actions Palette, Load the action called Bills In-Class Actions.atn from Exercises 8. To load additional actions, click on the Actions tab, click the small arrow with lines on the upper right part of the Actions palette, and choose "Load Actions..." from the list. The additional action or set of actions (in a folder) is then appended to the current list in the actions palette.

You may rename this new set of actions by double clicking on the folder icon in the Actions Palette and typing a new name. You may also drag an action from one folder to put it into another folder if you wish.

Batch Actions
For this exercise, we will batch process all the files found in the Actions Files folder (Exercises 8). We don't want to run the action over the network though because of bandwidth limitations and the increased possibility of errors and file corruption. So...

Copy the folder called "Actions Files" to your desktop. It contains a number of TIF files.

Create a new empty folder called "Actions After" on your desktop.

Choose File>Automate> Batch.

In the Set field, choose the Bills In-Class Actions set of actions.

In the Action field, choose Bill's Drop Shadow.

In the Source field, select Folder, then click the "Choose..." button and select the "Actions Files" folder by finding it and clicking on the Choose button at the bottom of the dialog box.

In the Destination field, choose Folder, then Choose and select the newly created "Actions After" folder.

Click OK to begin the batch processing of all the files. If done correctly, you should have the files saved in the Actions After folder with drop shadows added.

For further information about batch actions, check the Help menu item in Photoshop.

Recording a New Action
Creating a new action is as simple as letting the program watch the steps you make when you do something to a sample file. Open one of the files in the Actions Files folder to use as a sample file. To record a new action, click the upper right arrow in the Actions palette and choose New Action. Give it a name that describes the action, select the folder or "Set" of actions in which this new action will be stored. NOTE: If you wish to have a new Set of actions, create it first using the same upper right arrow button and choose New Set).

For purposes of demonstration, let's assume that you need 50 pixel-wide thumbnails of each picture in the Actions Files for a web page. Name the new action "Resize to 50 Pixels Wide".

Click the Record button. Photoshop now watches the steps you take and records them in the new action.

After the desired effect has been achieved, choose Stop Recording from the Actions menu list, or you can click the square "tape player stop button" icon located at the bottom of the Actions palette.

Remember -- don't forget to "Stop" your action once you are done recording!

To check on how it works, perform a File>Automate>Batch on the files contained in the Actions Files folder, and save them to a different destination folder.

A Useful Action for a Working Photographer
If you have a stock business and prepare scans for clients, make a series of actions that applies appropriate copyright information to the image. This eliminates the need to go to File>File Info and clicking on the Copyright & URL settings, then finally entering the information.

While each occurrence doesn't require significant time, the action is very handy when large numbers of files are being prepared.

I have visited Italy about 5 times and have about 600 illustrations prepared for a textbook about Italian renaissance art. I created 5 separate actions - one for each year that I visited Italy to photograph - and run the appropriate action once the scan is completed. It eliminates the possibility for spelling errors, and eases the annoying task of entering the copyright information repeatedly.

Digital cameras - benefits vs. disadvantages.
In-class discussion.

Where to find digital camera reviews?
There are a number of internet sites that review and compare digital cameras. A partial listing is:
Digital Eyes - http://www.image-acquire.com
Rob Galbraith Online - http://www.robgalbraith.com (this one is particularly interesting for news photographers)
Digital Photography Review - http://www.dpreview.com/
SLR Gear.com - http://www.slrgear.com

...and a good page discussing the quality of digital images is found at:
Luminous Landscape - http://www.luminous-landscape.com/tutorials/understanding-series/res-demyst.shtml

Long-term Storage of Information on CD ROM Disks, DVDs, and Other Media
CD-ROM disks are not as permanent as you may think. I've lost information stored on them after a year or two. Here are some tips for handling them to prolong the life of information stored on them.

Here's one man's account of trying to retrieve digital files that were only a few years old:
Jonathan Eastland's blog entry for September 10, 2006

Mike Johnston (editor of The Online Photographer) wrote a short article on finding the best CDs for storage. I've archived it at
johnston_on_cds.html

Here's another report on CD and DVD reliability that suggests DVD+R is better than DVD-R.
http://adterrasperaspera.com/blog/2006/10/30/how-to-choose-cddvd-archival-media/
This link, newer than the one above, claims gold disks are no longer needed with advances in surface sealing technology.

A very clever web production from the National Film Board in Canada about lost phones and the images contained in them. Could be converted into an animation easily.
http://pleasecall.nfb.ca/#/pleasecall

In-Class Technical Exercise 9:

Demonstrated to the instructor by Jun 1

Create an action that puts a visible 2-pixel Black outline around the files contained in the Actions Files folder, and writes them to the Actions After folder. After you create the action, show its operation to the instructor during class.

It must be completed and shown to the instructor by the last day of classes for the quarter to get any credit. Note that the "last day of classes" is BEFORE the last day of the quarter. No file needs to be provided - just a demonstration of the action working.

Plan ahead because I will not be continuously available and office hours become quickly filled during the end of the quarter.

Final Creative assignments:

Checklist of Specifications for the Assignment:
Number of pictures:	2 pictures, or one animation that has a good story line. Run time at least 30 seconds long if animation.
Picture size:	5x7 inch minimum
Resolution:	200 pixels per inch minimum
Color space:	Adobe RGB (1998) for RGB pictures, or grayscale Dot Gain 20%. N/A if an animation.
Text OK?:	NO, unless it's part of a scan you are using (book page, etc.)
Content:	Interesting and well-made pictures - open topic.
Prints required?	Yes, except for animations.
Animation Specs:	Animations, if chosen for the final project, are to be narrative, and be sized to 800x600 pixels. Frame rate must be 2 fps minimum, the length must be 30 seconds minimum. Above all, it must be interesting to watch. If it doesn't have an interesting story line, a poor grade will result. Avoid animation for animation's sake.
Print specs:	Portfolio-quality print on 8-1/2 x 11 inch (letter-sized) paper
File format:	JPEG, quality 7 or higher
Identification:	Put YOUR LAST NAME as the first word of the filename.
Assets Folder:	Required - see note below chart.
Destination:	Creative_04_and_05 folder

Notes: All digitized content (scans, digital photos, etc.) used in the making of your creative assignment must be submitted in a separate "assets" folder named "lastname_assets" (substituting your own name, of course.) This folder is due on the day that the assignment is due. Please don't copy your completed assignment into the folder though.

If the assignments don't meet the specifications given above, they won't be considered for a grade. That means if a file is submitted in sRGB instead of AdobeRGB, it gets a failing grade. Not having a quality print, not having a content folder with all contents, or not meeting the minimum picture size or resolution also results in a zero for the assignment. Please pay attention to the assignment specifications!

Open Topic
Two digital illustrations are requested. Open topic - exercise your creative freedom. Please don't use text in the illustration unless it is part of a picture you have included. If you type or draw text in the final illustration, there will be a one-letter grade reduction! If pictures do not meet the minimum size/resolution requirement or have been obviously "upsized", they will be given a failing grade! Have both pictures ready for presentation in class during the final exam time period.

Submit the files in JPEG format (Quality 7 or higher) to save server space, but be sure to also save the original layered file for your own future needs. Both files must be in the AdobeRGB(1998) working space to be considered for a grade. Animations are exempt from the color space requirement.

The files go into the Creative_04_and_05 folder. The assignment files are to be accompanied by portfolio-quality 8-1/2x11 inch prints of the files. The quality of the print (color, resolution, photo-quality, etc.) will be evaluated as part of the score for this assignment. Please print these before the final exam meeting - no printing will be permitted on the day of the final.

This creative work is due on the day of the final examination.

Tips for a better grade on creative assignments...

Final exam period schedule:
In addition to the two creative pictures, the final exam will be given during the exam period. The Registrar's Office is responsible for the final exam schedule, and a link can be found on my Digital Imaging start page. If there are discrepancies, please let me know and we will adhere to the Registrar's schedule.