Photoshop Techniques Part II

Photoshop Techniques
Part II
Selection & Interpretation

Gordon Osmundson

Burning & Dodging
P In the traditional darkroom, outside of the selection of your
materials, there are really only two variables, exposure and
contrast.
P Of course the entire print does not need to be given the
same exposure (or even the same contrast if you use multi-
grade papers, I never did this).
P This technique is known as burning and dodging.
P Photoshop has something called the Burn and Dodge tools,
but they really aren’t the same thing.
P What Photoshop does have are some tools to select
different parts of the image for different treatments.
P With these tools you can selectively apply any of
Photoshop’s interpretive tools, from sharpening, to tone
control, to filters, curves, etc.

The Selection Tools
Let’s take a look

P The tools we are going to study are the Rectangular
Marquee Tool, the Lasso tool and Polygonal Lasso Tool, the
Quick Selection Tool and the Magic Wand Tool.
P We will also look at how to refine the edge of our selections
and otherwise modify them.
P We’ve already used the Marquee Tool to crop an image, but
it has other uses.

Rectangular Marquee Tool

P We’ve already used the Rectangular Marquee Tool to crop
our images.
P We can also use it with the Patch Tool to cut and paste
small parts of our image into those empty wedges left over
from rotating or perspective correction.

Filling a Wedge
P First you need to put something in the wedge along
the edges of the image. Demo with NN #105
P With the Rectangular Marquee Tool, select a
narrow rectangle from the image that approximates
the area next to the wedge. Copy. Paste. This
puts a copy of your selection in a new layer over
the selection.
P Use the Move Tool to drag it into the wedge at the
edge of the image.
P Flatten the image. [Layer > Flatten Image]
P Repeat until you have something around all of the
edge.
P Now use the Patch Tool to fill in the rest of the
Wedge.

Selection Options
or Modes

All New Selection
Subtract from Selection

Add to Selection
Intersection of Selections

Lasso Tool
P The Lasso Tool is very simple, you can
do a free hand trace with it to select a
part of your image.
P You can also use it to deselect areas
selected with other tools.
P It only really comes into its own as a
selection tool when teamed up with
refine edge. More later.
P Just hold the mouse down and trace
around the area you want to select.
Release the mouse and the area is
automatically closed.
P Example <Crosshead, 8444>

Refine Edge
P Refine Edge gives us the tools to
blend our selections, much as we
might blend our burning and dodging
in the traditional darkroom.
P The principal controls that we use are
Feather and Contract/Expand.
P Feather blends the selection over an
area the of the number of pixels
selected.
P Expand/Contract expands or contracts
by the number of pixels selected
P Photoshop gives us a graphic
representation of what our selection
looks like as we modify it.

Adjust Feather and
Contract/Expand until you
have the selection you want.

Polygonal Lasso Tool

P The Polygonal Lasso Tool selects a
polygon by linking points that you select
with straight lines.
P This works well for selecting strait
edged objects.
P By closely spacing your points you can
also work your way around a curved or
otherwise irregular edge.
P Move your curser to the point you want
to use and click. Repeat. Double click
to close the selection.
P Example <Frame & Equalizers, NN93>

Frame & Equalizers
NN #93

With this image, I used the
Polygonal Lasso Tool to
outline the frame and brake
hanger so that I could
create a distinct difference
in tonality with the
background.

Quick Selection Tool
P This is a powerful selection tool that can select
irregular but tonally distinct areas
automatically.
P Hold the cursor down and move it around in
the area you wish to select. As you move the
cursor around, the area will be selected.
<Quintsentialy Nevada>
P Quick selection does not always get it right.
Some areas will be over selected, some under.
It depends on the tonality of the adjacent
areas. Zoom in and use Quick Selection again
to more accurately make your selection.
P Use the Subtract From Selection option to
clean-up areas that are over selected.

Note areas where snow has been selected in addition to the sky.
Use the Subtract From Selection option with Quick Selection to
clean this up.

Magic Wand Tool

P This is another powerful selection tool that can select irregular
areas of similar tonality. Example NN #80
P Click on a point and the area that it is in with a similar tonality
will be selected.
P You can adjust the band width or Tolerance of the selection.
Numbers between 10 and 50 can be used effectively depending
on what you are trying to select.
P You can select one contiguous area or all the areas in the image
with that tonality.
P By using the Add to Selection option, you can add to your
selection by clicking on points with a different tonality.

Options, Cont.

P [Select > All] - Selects the entire image. Needed for
perspective, distortion and some other global operations.
P [Select > Deselect] - Closes current selection
P [Select > Reselect] - Re-selects past selection. This allows
you to close your selection, make one or more global
changes, then return to your selection and work on it some
more.
P [Select > Inverse] - Selects the reverse of your current
selection. You can select one distinct part of your image, the
sky for instance, work on it, then switch to the rest of the
image and make changes without effecting the sky.

More Options
Expand & Contract

P This tool is especially useful when used in conjunction with the
Magic Wand Tool.
P Small details, like grain, can be added or subtracted from your
selection by using expand and contract in tandem.
P Expand by five or so pixels to select the grain that was missed by
the Magic Wand, then contract by the same number of pixels to
return to the larger outline of your selection.
P Conversely exclude small areas that Magic Wand picked up by
contracting then enlarging your selection. <NN#80 again>

One Last Selection Trick
Hiding the selection area

P Sometimes it’s better not to see the selection boundary. It’s
just easier to interpret the changes you are making.
P Use [View > Show > Selection Edges] to toggle the
boundary line off and on.

Selection Rap Up

P We’ve looked at the Rectangular Marquee Tool, the Lasso
tool and Polygonal Lasso Tool, the Quick Selection Tool and
the Magic Wand Tool, plus a number of selection options
including Refine Edge.
P You can use all of these tools together or separately to
make a single selection, both by adding to your selection or
subtracting from it. Getting the selection you want may
require using a variety of tools plus some ingenuity on your
part.
P I’ve been know to make a feathered selection and then cut a
hard edged piece out of it.

Interpretation

P We’ve now gone through how to prepare your image for
interpretation and how to select parts of it for individual
treatment.
P We can make changes not only to parts of the image but to
the image as a whole, that is global changes.
P Now let’s try to really make our photographs sing.
P We do this by making adjustments to our images tonality.
P We will first look at Brightness/Contrast

Brightness/Contrast
Image > Adjustments > Brightness/Contrast
P This sounds like just the ticket, the same two basic controls
we had in the traditional darkroom. We can lighten or
darken the image and change the contrast.
P But wait, the way that Adobe has set this up it is easy to clip
our images and once clipped, the information is lost.
P In the darkroom this wasn’t a problem, all the information
was in the negative and we adjusted our exposure and
made another print. We could go back in Photoshop but we
would lose whatever else we did.
P Photoshop offers us some much better tools that don’t work
like our old traditional darkroom controls.
P Next stop, Levels

Levels
Image > Adjustments > Levels
<Ctrl L>

P You can do a lot with Levels and it’s included with Photoshop
Elements, while Curves is not.
P Look at the histogram and note the three small arrowheads
below the histogram itself. They are marked 0, 1.00 & 255
P This arrow heads can be moved left or right. Moving the left
arrowhead adjusts the darkest part of the image, the right
arrowhead lightest.
P Moving the center Arrowhead changes the average value of the
image making it appear lighter or darker overall.<Box Poc Driver
& Rod, SP 4449>

P In the upper image no
changes have been made.
P In the lower image the left
arrow has been moved to
the shadow clipping point at
12 and the right arrow has
been moved to the highlight
clipping point at 241. This
was actually done using the
Auto button. This has
increased the overall
contrast.
P The center arrow has been
moved from 1.00 to 0.79
darkening the image overall
without changing the
darkest and lightest values.
P Click Okay and the changes
are saved.

Curves
Image > Adjustments > Curves
(Use Show all Menu Items)
<Ctrl M>

P When I was using Photoshop Elements, I used Levels a lot,
but I wanted to do more. My primary motivation for getting
CS3 was to have access to Curves.
P Let’s first look at doing with Curves what we just did with
Levels. Note the two arrowheads below the histogram, they
do the same thing as the left and right arrowheads in Levels
except that we can turn on Show Clipping and actually see
where clipping would occur. <Box Poc, etc.>
P

Curves
Image > Adjustments > Curves
(Use Show all Menu Items)
<Ctrl M>

P To lighten or darken the image, we
use our cursor to grab the midpoint of
the curve and pull it down and to the
right or up and to the left.
P This is a very useful operation and for
it I set up a series of preset curves
moving the center point 1, 2, 3, 6, 9 &
12 points down and to the right, or up
and to the left.
P These preset curves are a handy and
regular way to make adjustments,
particularly fine adjustments. <Box
Poc, etc.>

Preset Curves
P If you make a curve you wish to
save there is a tool for that, see
below and the down arrow at
left.
P Adobe gives us a number of
preset curves. Lets take a look.
P I’ve shown their Medium
Contrast curve at left.
P It makes an image darker and a
little more contrasty.

In the upper image
there have been no
changes. In the lower
image we have used
Adobe’s Medium
contrast Curve.

The darker areas are
a little darker and
there is more contrast
through the middle
tones. The highlights
seem brighter due to
their contrast with the
overall darkening of
the image.

Linear Contrast
P One of the curves that Adobe
gives us is called Linear
Contrast.
P I’ve shown their Linear Contrast
curve at left.
P I wanted to see what this did so
I took a look. The clipping
points are not changed so there
is no effect on the darkest or
lightest values.
P The shadow areas are slightly
depressed and the highlights
slightly elevated.
P The response curve is a little
steeper through the middle
values.

Linear Contrast
P One would think that with no
change in the high or low values
that the overall contrastiness of the
image would not change, but it did.
P What has happened is that while
the clipping points have not
moved, more of the images values
are both lighter and more darker
than before. That with the steeper
contrast in the middle values
makes it look more contrasty.
P Note that this curve is symmetrical
making it simple and easy to
understand the effects. Adobe’s
other curves are not symmetrical
giving more weight to the shadows.

Linear Contrast
P I thought that this was a useful
curve, but I wanted to be able to
do more with it.
P I therefore developed my own
version of it, in fact three versions
of it.
P I took the quarter points of a
straight line curve and moved the
left point down and to the right 3,
6 & 9 points and the right point up
and to the left 3, 6 & 9 points.
This gave me three distinct
curves which I labeled Linear
Contrast I, II & III.
P Linear Contrast II is shown at left.

In the upper image I
have moved the D-Max
point over 16 points to
the right making the
darkest part of the
image maximum black
and darkening the
image overall.

In the lower image I
applied my Linear
Contrast II curve to the
image above. Note
how the contrast has
increased and the
image looks snappier
and is beginning to
have an overall
glowing quality to it.

Taking this a Step Further

P After exploring the effects of Linear Contrast, I began to
think, “If darkening the darker parts of the image and
lightening the lighter parts gives us more contrast, if we
pushed this farther into the shadows and farther into the
highlights could we do more?”
P Then I had an epiphany.
P What I was thinking about was like a curve we have looked
at before. Furthermore, if we used that curve our ink jet
prints would look much like Silver Gelatin prints.
P That curve, of course is . . .

Response Curve for Silver Gelatin Paper

Shoulder
D-Max or
Maximum Black

Straight Line Section

Paper
White
Toe

The Toe & Shoulder Curve
P Working in the traditional darkroom, the toe and shoulder of the
paper’s response curve often present problems. It could be
difficult to hold detail in the shadows and still get a convincing
black, likewise in the highlights it can be hard to hold detail and
still make the highlights sparkle.
P But if we compare the silver gelatin response curve to that of
the digital capture JPEG, we start to see that it is this curve that
gives the traditional silver gelatin print its dramatic look. The
shadows are dark, but still hold detail, contributing to the graphic
design of the image. While we try to avoid paper white in the
highlights, their contrast with the darker tones in the rest of the
image can make them sparkle. At the same time the contrast
range in the middle tones is greater than what we actually find in
the textures of the subject itself.
P While working with the toe and shoulder always presented
problems, we now find, that in reality, that they are really our old
friends.

The Toe & Shoulder Curves, Cont.
P Starting with the linear response curve, I developed four new
curves by adding a point towards the ends of the curve that
bent the curve out to give it a toe and shoulder. The
difference between the four curves lay in the steepness of
the middle straight-line section and in the radius of the toe
and shoulder.
P The two steepest curves proved to be too steep for all but
the flattest images. The other two curves did not give as
fine a control as I wanted, so I developed some intermediate
curves. Eventually I had a total of seven curves which I
numbered 1 - 5 plus #7 and #9. The numbers represent the
offset the intermediate points, that is the curve number down
and to the right and up and to the left of the left and right
intermediate points.

The Toe & Shoulder Curves, Cont.
P I’ve included all of the curves set points in the handouts so
that you can enter them into your own copy of Photoshop.
Please feel free to experiment with these curves yourself.
P In practice, I find that most black-and-white images are best
served with curve number five.
P You can also use these curves on color images. Curves
numbers two and three will make colors seem more vibrant
and alive.
P Note that these curves will make a dark image darker and a
light image lighter. We can adjust this by using the
darkening and lightning curves presented earlier. As these
curves will reduce some of the increase in contrast we just
made, we may wish to further tweak the image by using one
of the lower numbered toe & shoulder curves. Indeed, we
may need to go back and forth with this several times to
fine-tune our image. <Flyer in Late Afternoon Sun>

Without Toe & Shoulder
Curve

With #4 Toe & Shoulder
Curve

Without Toe & Shoulder
Curve

With #3 Toe & Shoulder
Curve

Shadow & Highlight
Image > Adjustments > Shadow/Highlight

P I was reading an article about working in Photoshop where I
saw a description of the Shadows/Highlights command.
What this tool does is it takes any information in the
shadows or highlights and expands it, increasing its contrast.
That is it is kind of the reverse of the Toe/Shoulder curves
just described. But it doesn’t work in quite the same way.
P It actually analyzes the image and determines where that
detail can be found and expands it.
P What this means, is that we can take the information in the
toe and shoulder and bring it back, but if we are careful we
can do it without degrading the graphic effect of the
shadows and highlights that we developed with the Toe and
Shoulder curves. <Flyer in Late Afternoon Sun>

Shadow & Highlight
Image > Adjustments > Shadow/Highlight

P Nonetheless it can be useful after using Shadows/Highlight
to go back and further tweak the toe and shoulder with one
of the low numbered Toe & Shoulder curves.
P Again this can be a process of ever finer tweaking of the
image until we get the effect that we want.
P Let’s take a closer look at how to use the Shadow/Highlight
command.

Shadow & Highlight
P At left is the Shadow/Highlight dialog
box. I have shown what I use as my
default settings. These should be
taken as a starting point as you may
wish for a more subtle or a larger
effect.
P Both the shadow and highlight boxes
work in the same way. The upper
slider allows you to adjust the amount
of effect that is being produced, while
the middle slider adjusts how far up
or down the tonal scale the
adjustment will take effect. Both of
these can be used quite effectively.

Shadow & Highlight

P The radius, or the third slider, has to
do with the number of pixels that the
program is analyzing. I always just
leave this on the values shown here.
P I don’t use the Adjustments box very
often and will leave it to you to
experiment with it. <Eccentric
Crank, SP 4449>

Scanned Print Scanned Negative Processed in
Photoshop
Note the shadow detail in the driving wheel brought
out with Shadow/Highlight in the right print

Our Tonality Toolbox
P We now have three powerful tools for adjusting the tonality
of our images. We have darkening and lightning curves, we
have the toe and shoulder curves and we have the
Shadows/Highlights command.
P We can go around and around with these tools making ever
finer adjustments until we have the basic analogy of our
image established. We can also use them on portions of
the image that we have selected using the selection tools
previously discussed.
P For me these are the essential tools, but there are some
others that can also be useful. We’ll take a look at the
gradient tool, the paintbrush tool, and the burning and
dodging tools. But first a look at a tool called Black & White
that is designed for selectively changing colors to black &
white.

Black & White
Image > Adjustments > Black & White

P With a scanned color slide or digital capture image, you ca
convert it to black & white by simply discarding the color
information [Image > Mode > Grayscale] or you can adjust
the gray scale interpretation of each color using Black &
White.
P We can, for instance, interpret blue as being darker than it
would normally be giving something of the effect of a yellow,
orange or red filter making the sky dramatically darker.
P Warning strong use of this will exaggerate image flaws, and
increase digital noise.

Black & White
Image > Adjustments >
Black & White

P At Left is the Black-and-
White dialog box.
P Opening this box converts
the image to grayscale.
P Now simply move a slider of
the desired color to make it
darker or lighter.
P Adobe has also given us
some presets that simulate
various color filters among
other things.

The Gradient Tool
P The next thing that I would like to talk about is the gradient
tool. This tool provides an even blended Darkening or
lightning of a part of the image. Is it is most useful for edge
burning, but you can use it any place you want a gradual
adjustment to a part of the image.
P What is edge burning and why would we do it? It’s burning a
slight darkening of the edges of our image. It is a subtle
adjustment that requires a careful examination to notice but
does have subtle effects on our viewing of the image.
P This was more necessary in the traditional darkroom light
from the enlarger tended to fall off slightly towards the edges
of the print due to the greater distance between the lens and
edge as contrasted with the center. But it has a edge
burning has interpretive effects as well.

The Gradient Tool
P It helps to counter act the glare from the
surrounding white of the printed page or
museum mat board.
P It helps to draw our eye towards the center
of the image and not outward towards the
edges.
P It helps to also give us a more distinct
change of tonality between the edge of the
image and the printed page or mat board.
This helps to solidify the impression our
image makes.
P Finally, if the edges of our print are slightly
darker, we can make the center slightly
lighter, helping to give our print a glowing
quality.

The Gradient Tool
P With Gradient, I usually set the
mode to darken, an opacity of 5
to 15% and I have it set for
Reverse and Transparency.
P With these settings I put my
mouse pointer at the spot I want
the gradient to begin and then
move it towards the place where I
want it to be at its darkest.
P If you hold the shift key down
while you do this for a Lineal
Gradient, the direction will be
perpendicular to the side of the
image.
The Lineal Gradient runs across the image in a straight
line. The Radial Gradient extends out in a circle with
the radius point where you first place the mouse
pointer.

Paint Bucket
P The paint bucket tool is very simple it fills a
selected area with a color.
P If you set tolerance to 255 it colors in the
complete area. If you set tolerance to a
lower number it will select an area to fill in
in the same way as the Magic Wand tool
selects an area.
P If you don’t wish to completely cover an
area set opacity to less than 100%.

Paint Bucket
P A handy way to select the color or opacity
that you wish to use is the eye dropper tool.
Simply position the eyedropper in the
image at the color or tonality that you wish
to duplicate and click.
P The color or tonality will be displayed in the
Set Foreground Color box.

Paint Bucket
P The primary use I have for this tool is to replace some
rather rough looking or unevenly developed skies in historic
negatives.
P I would select the sky area using the magic wand tool,
select the lightest tonality in the sky with the eyedropper
tool, then with the paint bucket fill in the sky.
P We don’t yet have a very convincing looking sky. The
typical sky is lightest towards the horizon and darkest
towards the zenith. So use the gradient tool to darken the
sky towards the top of the image. An opacity of about 15%
works well for this but I would encourage you to experiment
with other values for your particular image.
P I also like the engine burn the sides with the gradient tool
usually with an opacity of about 5%.

Dodge & Burn
P Photoshop gives us both the burn tool
and the dodge tool.
P I think these are both pretty self-
explanatory and I used them a lot
when I was first working with
Photoshop. I no longer use them
very much, preferring instead to use
the selection tools would curves and
some of our other interpretation
options.
P I still occasionally find it convenient,
however, to use these tools to make
local increases in contract.

Dodge & Burn

P For instance, I might wish to brighten
up the lettering on the side of a
tender. I would select dodge and set
the Range to Highlights with perhaps
a 15% Exposure.
P Next I would set the Brush size
Master Diameter to slightly larger
than the width of the lettering and
then simply trace the brush across
lettering.

Conclusion
P We’ve looked at how the eye sees, how film sees, how
digital capture sees, we’ve taken a brief look at the zone
system, etc. We’ve examined the response curve of film
and silver gelatin paper and how they give black & white its
dramatic character.
P We’ve worked over our scans and digital capture images to
refine our compositions, remove defects and even give them
a large format, view camera look.
P With Photoshop’s tone control tools, we tend to make more
global corrections to our images than in the traditional
darkroom. Still different parts of the image call for different
treatments and Photoshop gives us gives very precise
selection tools for this.

Conclusion
P Next we’ve taken a look at Photoshop’s tone controls
particularly Curves and how we can use Curves to create
that silver gelatin look. In fact using Curves in conjunction
with Shadow/Highlight we can overcome some of the
limitations of traditional materials.
P Finally we took a look at how to convert color images into
black-and-white and closed with a look at a couple of other
miscellaneous tools.
P In the remaining time I like to open the floor for questions.

Toe & Shoulder Curves

Contrast I 20/24, 74/76, 128/128, 181/179, 235/231
Contrast II 19/25, 73/77, 128/128, 182/178, 236/230
Contrast III 20/30, 72/78, 128/128, 183/177, 235/225
Contrast IV 19/31, 71/79, 128/128, 184/176, 234/222
Contrast V 20/34, 70/80, 128/128, 185/175, 235/221
Contrast VII 13/37, 68/82, 128/128, 187/173, 241/217
Contrast IX 26/51, 66/84, 128/128, 189/171, 229/204

Reverse Contrast -I 24/20, 76/74, 128/128, 179/181, 231/235
Reverse Contrast -II 25/19, 77/73, 128/128, 178/182, 230/236
Reverse Contrast -III 30/20, 78/72, 128/128, 177/183, 225/235
Reverse Contrast -IV 31/19, 79/71, 128/128, 176/184, 222/234
Reverse Contrast -V 34/20, 80/70, 128/128, 175/185, 221/235

Linear Contrast I 61/67, 128/128, 195/189
Linear Contrast II 58/70, 128/128, 198/186
Linear Contrast III 55/73, 128/128, 201/183

Darken + 01 127/129
Darken + 02 126/130
Darken + 03 125/131
Darken + 06 122/134
Darken + 09 119/137
Darken + 12 116/140

Lighten -01 129/127
Lighten -02 130/126
Lighten -03 131/125
Lighten -06 134/122
Lighten -09 137/119
Lighten -12 140/116

Photoshop Techniques Part II

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