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NOTE: Photoshop menus are referred to using the following convention
in this protocol: "select copy from the edit menu" is
abbreviated EDIT>>COPY.
1. Open Image
2. Save As
- After opening the image save it immediately using the naming scheme
below with FILE>>SAVE AS. This is very important to protect the
original image.
- The new name should be the original name with the addition of EDIT
to the end.
- ASK-03-0048-oc-YHS-01.tif will be saved as ASK-03-0048-oc-YHS-01_EDIT.tif
3. Rotating the Image
- If the image is upside-down rotate it to the right way up by selecting
the following:
- IMAGE>>ROTATE CANVAS
- Choose degrees necessary (if upside down choose 180º)
- After rotating image check scale is in the correct position.
4. Moving the Scale to a New Layer
- Select the Rectangular Marquee Tool (see above figure)
from the toolbox. This is the rectangle with the dashed outline
in the top left.
- Use marquee tool to outline only the scale.
- Cut and paste scale. (This will automatically create another layer.)
- !!Before editing image check that you are working in the correct
layer.
5. Clean Up the Background of Image
There are a couple of different ways to do this. If the background
is relatively clean and the fossil's edges contrasts sharply with the
background you can use the Magic Wand Tool method.
5a. Magic Wand Tool method

- Click on Magic Wand Tool in the tool window (see
above left). Click on the background of the image. If the selection
does NOT find a good line around the edge of the specimen, change the
tolerance (above right) and try again. This may have to be repeated
multiple times. Do not worry if there are areas of the background
selected as long as the specimen is bounded by a line that does not
connect to areas of the background.
- If the backgroud does not make a good contrast with the specimen
edges and your Magic Wand Tool selection is useless,
the Magic Wand Tool may not be able to properly outline
the fossil. In this case skip to 5b Magnetic Lasso Tool/Lasso
Tool Method and start over.
- Remove the backround selection ghosts. If your selection grabbed
some of the back ground, but still has a good border around the specimens,
do the following to restrict the selection to only that around the specimen.

- Select paths from the "Layers-Channels_Paths" box
(above left).
- Click the "make path" button (yellow arrow in above right).
- Use the Direct Selection Tool to select only the
path bordering the specimen edge. You may have to repeat the whole
process starting with the selection if this does not work out.
- Click the "make selection" button. The click
any area (ie the pink "CLICK HERE" box above right) of the
"Layers-Channels_Paths" box to de-select the path. Click
the "Layers" tab in the "Layers-Channels_Paths"
box . Skip to
5b Magnetic Lasso Tool/Lasso Tool Method

- Select Magnetic Lasso from toolbox (yellow arrow
above). If you do not see the magnet in the tool icon, click and hold
the small triangle in the bottom left of the box (blue arrow) to
select it.
- Press “caps lock” to get cross hairs.
- Study the edge of the specimen...memorize it.
- Zoom into specimen as close as possible so the individual pixels can
be easily seen.
- *Focus carefully on what exactly it is your doing, which is grabbing
the edge.
- When you have gone around the whole fossil click on the beginning
anchor to complete the outline/path.Lasso Tool
- When you have a path around the fossil. Use the Lasso Tool
while holding "shift" or "option" to add or subtract
parts of the selection. This may take some practice.
- The Lasso Tool is in the same box as the Magnetic Lasso Tool. Choose
the Lasso from the menu (blue arrow in figure above).
6. Background Deletion
Once the fossil outline is clearly defined you will need
to expand the outline slightly to make sure all of the fossil is included
in the outline.
- Expand the Outline'
- SELECT>>MODIFY>>EXPAND (You will need to choose pixel
value for expansion. This will have to be done on a case by case
basis [usually somewhere between 5 and 10]).
- Feather
- The next step is to feather the edge of the fossil image so that
it does not look like a cut out. Feathering blends the edge of the
fossil seamlessly with the background.
- SELECT>>FEATHER (choose a value half of what you used to
expand).
- !Always feather before select – inverse (see next section)
- Make Background Black
7. Change to Grayscale
- Converting an image to Grayscale can be done before or after editing
the image depending upon which view (color or grayscale) facilitates
easy editing. With difficult images, it is best to work in color until
all changes have been made, then to convert into grayscale, though this
will be dependant upon the photo editor’s preferences.
- Changing to grayscale after editing will prompt Photoshop to ask if
image should be flattened.
- !!!Do not flatten image.
- IMAGE>>MODE>>GRAYSCALE
8. Levels
- Levels are used to adjust the contrast of the image.
- To get to the Levels: IMAGE>>ADJUSTMENTS>>LEVELS
- The Histogram is a representation of the black and white output of
the image. Everything to the left of the black arrow is considered pure
black. Everything to the right of the white arrow is considered pure
white. Move the arrows accordingly to adjust the contrast of the image.
- *Do not move the white arrow into the histogram as this will cause
the image to become overexposed. If you are uncertain about the appropriate
contrast, skip this step and just save the file as is.
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