Laser Engraving Photos

who am i
40 years in the awards and engraving business
Manufacturers Rep since 1988
Has been selling lasers since 1991
Have been using CorelDraw since 1991
Featured writer for the Engravers Journal
Constantly calling on Engravers and Trophy shops

who am i
My lines include
Full line of Trophy Supplies such as resins, glass, plaques, and
acrylics
Custom Castings
Full Line of solid wood and custom manufacturing
Full line of engraving equipment, sublimation and engraving
supplies

Who Am I
• My email is
• mike@engrave.ca
• My website is
• www.engrave.ca

our lesson purpose
My purpose today is to make you a better
photograph engraver using your laser machine
I will take you through my 4 rules for successfully
lasering photos
The second part of this seminar will look at the
steps needed for each material that we want to
engrave.

why 3 hours
Some people asked me why I need 3 hours.
I need 3 hours because there are a number of
factors and techniques you need to consider when
you are lasering photographs.

please have patience
I have spent years developing the techniques we
discuss here
A number of them I have developed myself
These techniques are new because everyone
wants to think that they can tell people to just buy
software and it works

One Stop Photo Software
A lot of people talk about buying photo processing
software for the laser as if it is the only
consideration when it comes to laser engraving
photos. Although photo manipulation is important it
is not the only one techinque that we need to know
There are a number of factors and techniques that
will determine whether you are successful or not at
processing a photo for your laser
Spending $250 does not give you a free pass to
guarantee a perfect photo

4 Factors For a Good Photo
• Rated in order
A Good Quality Photo
Proper Power and Speeds for your laser
Know your material
Software

Good Quality Photo
There are a number of ways to look at what
constitutes a good photo
Is the lighting good?
Is there good detail?
Is there good focus?
Most importantly does the file suffer from too much
compression (artifacting)?

Good Lighting
Bad Lighting Good Lighting

Good Lighting
To Much Red Colour
Red colour cast
Good Normal Colour

Good Lighting
This Image Comes
Up to Dark
This Image Comes
Up Just Right

Good Detail
To Far Better Detail

is our image all there
GoodBad if you are
looking to
laser the tractor

is the image to compressed
Bad Good

JPEG Compression
One of the big problems that we face is that most
photos that we are given now a days by our
customers have been taken on a Digital camera.
The problem with digital camera’s is you just never
know the quality of photo you are going to get in
terms of the compression that was used when the
photo was made. The higher the compression the
worse the image will be for lasering
Highly compressed photos can greatly decrease the
chances of achieving a good photographic
representation on your laser

JPEG Compression
For this reason it is very important that we analyze
a photo when we get it so that we can check for
compression issues that would effect the quality of
our photo
If the photo you receive has a high degree of
compression this should raise a red flag in terms of
being cautious as to the results you will get from
lasering the image.

it is a good idea to zoom in
on an image
Zoom in on the image to check the quality
This photo is of very good quality
CorelDraw

it is a good idea to zoom in
on an image
Zoom in on
the image to
check the
quality This
photo is not
very good
quality

Here is how it lasers
The image has
been lasered on
black anodized
aluminum. The
detail is not there
because of all the
compression
applied

Same Image just less
compression
Here is the same image less compression

Same Image just less
compression
The image has
been lasered on
black anodized
aluminum. The
detail is a lot
better as there is
a lot less
compression
happening

Here is Another issue with
Compression
Zoom in on the image to check the quality. On the left
you see how there are chunks or blotches in the yellow
circles. You can see what happens to the image in the
Unsharp Mask. The blotches a very pronounced

Too much compression causes
blotchiness in our image
When there is a
lot of
compression
blockiness when
we go to sharpen
we end up with
large “blocks”
which is no good
for our image

Or is the image just no good to
begin with
OriginalConverted

Proper Power Laser Settings
Probably one of the areas where most laser users
miss is making sure their laser settings are set
properly for the material that they are lasering on. I
call this maximizing your powers and speeds for a
material
One of the first steps we should do when we get our
laser is to create the proper power and speed settings
for each one of the materials we are going to work
with - and I mean all of them. Save them all.

Do not believe what your laser manufacturer tells
you is the proper power and speed

Here Are Some Manufacturer’s
Presets
I would be at least 10
to 15 % lower
Notice this is for
marble not granite
300 DPI 400 DPI 600 DPI
Speed to Power

As you can see the laser settings that are listed by the
manufacturer are not the ones that I would use.
To be fair - with all the materials that are available it is
hard to have proper powers. For example when we say
engraving plastic there are so many variations which one
would you list is hard to decide.
Also everyone is different. For example I may like a
deeper engraving than someone else. Thus my power
and speed will be different from someone else. So as you
can see it is very hard to have so called factory presets.

So for this reason it is very important that you test you
materials so that you get the best combination of power
and speed
And to be more precise we should have a proper power
and speed for the resolution you want to run whether is
be 300, 400, 500 or 600 DPI.

Sample file done on
anodized aluminum
The Manufacturers setting was 100 s 40 power. There is
suppose to be an emblem in the background.

Sample file done on
anodized aluminum
100 Speed 30 Power 600 DPI. There is to much power
being used on this material

Sample file done on
anodized aluminum
100 Speed 20 Power 600 DPI. The detail is coming up

Sample file done on
anodized aluminum
100 Speed 12 Power 600 DPI. So much better detail

Sample file done on
anodized aluminum
100 Speed 12 Power 600 DPI - Perfect Image

Sample file done on
anodized aluminum
Original Power
30 Power
Final Power
12 power

Here is another example
This is a difference of 3 percent in power. Same speed
Missing
Line
Bolder
Font
Less Power
More Power

Here are 3 vector and 3 raster lines engraved
at different powers and the same speed
Notice how the vectors
line increase in width as
the power increases
Notice how the raster
line increase in width as
the power increases

Here is one more example
Here is another example of too much power - black granite

how can we explain this over
burning
So the question for us here is to understand what
is going on in terms of explaining why this over
burning is happening. What is going on is the
higher the power we use (which could also be
slower speed) the bigger the laser dot becomes.
The bigger the laser dot that is created by the laser
the more material that is removed by the laser
through this larger dot.

Dot Gain
Thus as our power increases or our speed
decreases our laser spot size increases. This is
because our power increases. If our power goes
down or our speed goes up our laser spot or dot
becomes smaller
When it comes to explaining this rule I call this dot
gain - which is the same term used in the printing
industry. The more ink you use the “bolder” the
image becomes

What is going on?
This is a very important rule that must be
considered when we are working with any material
on our laser. If our dot gain becomes to much we
can obliterate our image.
I remember the first time I tried to laser a photo
onto black granite. I used 100 power and 100 speed
on a 75 watt laser. All I got was a big white
rectangle. I had so much power there was no image
left

Dot Gain - the shape of a
lasered dot
The Yellow Circle
is the Original laser
beam spot size
The area outside of
the yellow circle is
the so - called “gain”
that happens when
the heat spreads out

Another laser spot
The Yellow Circle
is the Original laser
beam spot size
The area outside of
the yellow circle is
the so - called “gain”
that happens when
the heat spreads out

Dot Gain creates the over
burn
So the way that dot gain works is the higher the power
you produce with your laser the bigger the gain
becomes and thus the spot size becomes bigger
For example if your creates a laser spot size of .005
when it hits your material that is the size of the laser
spot. As more heat is absorbed by the material our spot
size could grow to a size of 0.025 or 5 times the original
size. If the power is too much it can “interfere” with
neighbouring spots or dots.
This is why images become “thicker” due to over burn.

burn
The bigger the size of the spot the more overlap we
get between the laser dots. Combine this with higher
resolutions and we can create a lot of dots in a 1
square inch size.
This is why images become “thicker” due to over
burn. Over burn will quickly obliterate our image

burn
Thus it is critical that we get our laser powers perfect
Remember power can be expressed in a combination
of laser power, motion speed and printed resolution
(such as 600 DPI)

Normal Laser Spots
Let us assume that the diagram below is a rendition
of a series of laser dots or spots laid down at a proper
power and speed. In this case we have our spots
touching

To much power
If we use to much power our spots become bigger.
Our offset will remain the same. Thus we now have
spots running into each other

little To power
If we use to little power our spots become smaller.
Our offset will remain the same. Thus we now have
large spaces between our spots. This can mean some
parts of our image may be gone due to not enough
power by the laser.

printing Resolution
Laser printing resolution is the amount of laser dots
or spots that are laid down in a 1 inch box. The
acronym DPI stands for dots per inch.
The higher the DPI theoretically the better the quality
we will get. This is not always right but for the most
part it is.
400 DPI means 400 dots horizontally and 400 dots
vertically. 600 DPI means 600 dots horizontally and
600 dots vertically.

printing Resolution
The more dots that we print the more overlap we will
have.
For this reason increasing the resolution will increase
the amount of laser burning in an inch box. This is
like dot gain but the spot sizes remain the same. What
changes is the overlap.
The higher the resolution the longer it takes to
engrave as we have more lines
Never use 1200 DPI for photos. It is not necessary

printing Resolution
400 DPI
600 DPI
Here are two representations of two different printed resolutions.
The red box is representing a 1 inch box. The spots are the same
for each. The 600 DI has more lines than the 400 DPI. Thus there
is more overlap and thus more burn by the laser in the inch box.

now that we have a better
understanding of what is
resolution and dot gain let us
look at how to create proper
power and speed settings

Two Ways to create proper
settings
1. One is to create a black box and adjust your power
and speed settings as you laser
2. The second is to use colour mapping to run multiple
powers or speeds at the same time
There are two ways to create proper laser tests

using the black box
All though I tease everyone when I go through this
step to try and get them to think it is some super
secret technique it is very easy and most machines
will support this technique
The First Method is to Use the Black Box

using the black box
The black box method is easy because all we are
doing is sending an image (black box) over to the
laser with a preset power and speed
Once the job starts we start adjusting our power or
speed from our laser machine.
As we are adjusting our power or speed we are
monitoring the burn to see if it is satisfactory

using the black box
The big question is what is a proper power and
speed?
Some of it really depends on you and what you
consider a proper power. For example if we are
engraving wood the proper power will be what
depth you want to laser at.
To me pretty is in the eye of the beholder. What you
think is right may not be right in my eyes.

Golden Rule
The Proper Power and Speed typically is the least
amount of power that we can get away with but still
get a good quality looking image.
This may seem a little foreign considering no one
really explains how the manufacturer derives the
power and speeds that they suggest.
Just remember the more power you use the less detail
you can create. Considering we want detail than
using less power is preferable over too much.

First create a black box in
Coreldraw
Our Black Box
Our Box is 2 “
wide and 3” tall
The box an be
any height just
choose
something that
will run for a
minute or two

Set up the printer driver
Set Up For Anodized Aluminum on a 60 Watt
Notice How Low the Power is
Printing Resolution
Only Raster
Raster Speed
No Vector Setup

adjust the power on your
laser machine
Speed Button allows us to select the speed and adjust it
The Power button allows us to select the Power and adjust it
The Up and Down arrows in the red box allow us to change the value

Adjust the power or speed as the
machine moves

for vectors we need to keep sending
different power and speed jobs
insert vector video

Here is our box engraved
Notice how the
rectangle skews
inwards where the low
power burn is
Our Sample
Material was
Brushed Gold
Engraving Plastic

Save the settings in the print driver

using colour mapping
Sometimes when we need to test a material adjusting the
power as we go does not work that well. One example is
with Thermark. I can adjust the power or the speed but I
can not see my adjustment till I wash off the Thermark
on steel or tile. It is not very practical to laser, wash off,
clean, respray. This goes the same for glass that we
mask.
For this reason it is better to run a number of settings all
at once. We do this with colour mapping.
The Second Method is to Use Colour Mapping

Sometimes when we need to test a material
adjusting the power as we go does not work that
well. One example is with Thermark. I can adjust
the power or the speed but I can not see my
adjustment till I wash off the Thermark on steel or
tile. It is not very practical to laser, wash off, clean,
respray. This goes the same for glass that we mask.
For this reason it is better to run a number of
settings all at once. We do this with colour
mapping.

Engrave by colour
testing File
Here are a couple
of testing files
where I use
colour mapping.
Each colour
represents a
different setting

Engrave by colour
testing File
Here are a couple
of test patterns
that I created on
ceramic tile.
Notice how the
Thermark spray
adheres at
different setting.

Help File
Go to this link to
see a more
through
discussion on
this topic. You
will be able to
down load the
test file.
http://www.engrave.ca/archives/5348

know what type of photograph
you are working on

the difference between black and white
and grayscale
Black and White Image Grayscale Image
Our grayscale image looks better than the error diffusion image
Error Diffusion Image Continuous Tone Image

Know Your Material
Fine or coarse
Ok here is the number one rule of being successful
with lasering photos. The way we process a photo is
dependent on the type of material we are lasering on.
If we look further into this statement we see that we
actually come out with two types of material. We
have what I like to call fine and coarse material.
Depending on the material type will determine the
way I process my photo.

Grayscale looks better on fine
material
Error Diffusion Image Grayscale Image
Our grayscale image looks better than the error diffusion image
Good Best

Error Diffusion looks better on
coarse material
Error Diffusion Image Grayscale Image
Our error diffusion image looks better than the grayscale image
GoodBest

Fine Material
Fine material is the first of our two types of materials
that we classify our material into
What is a “Fine Material”?

Characteristics of fine
material
Large Contrast (white or black)
No Grain (engraving plastic)
Able to hold a good dot
Able to hold a small dot
Typically requires lower power

Types of fine materials
Laserable Plastic
Anodized Aluminum
Laserable Aluminum
Black Blass Plated Steel
Leather
Acrylic
AlumaMark

Coarse material
Coarse Material - coarse material can be classified as any
material that has a lot of grain in it and or it can not hold
a small lasered dot. For example oak would be a very
coarse material because it has a lot of grain in it -
actually a very bad grain when it comes to lasering. For
that matter all wood is coarse. For me the coarser the
material the less detail we will leave in our image - more
on that later.

characteristics of coarse
materials
Low Contrast
Lots of Grain
Able to hold or create a large not small dot
Typically requires higher power
The photo looks better when we remove the background
- use Cutout Image

types of materials
Wood
Marble
Glass
Thermark Materials
Mirror
Corian
Fabric

Material chart
Fine Materials Coarse Material
Anodized Aluminum Granite
AlumaMark Thermark Materials
Engraving Plastic Glass
Mirrored Acrylic All Wood Products
Acrylic Corian
Laser It Mirrors
All Laser Engraving Metals Marble

Why Do we have fine and
coarse materials
The reason we need to place our materials into these
two different categories is that we will process our
photos differently depending on whether the product
is a fine material or a coarse material
Thus the product we use will dictate how we process
a photo.

Processing a photo
We will now go through the steps on how to process
a photo.
Note that the initial steps are the same for each photo
except there is an extra step for coarse materials

processing a photo for
lasering fine material

Here is my image
All images need to converted to grayscale first

Fine material steps
anodized aluminum
With the image selected go to
BITMAPS | MODE | GRAYSCALE

What does a proper grayscale
image look like
This is what a proper grayscale image should look like. Notice
that it has a good level of variation in light to dark

Fine material steps
anodized aluminum
Image converted to gray on the left is to dark. The image on the
right is lightened up with the contrast enhancement tool

Fine material steps
anodized aluminum
To access the contrast enhancement tool go to
EFFECTS |ADJUST | CONTRAST ENHANCEMENT

Fine material steps
anodized aluminum
Our image is to dark. The
histogram shows this
Original Preview

Fine material steps
anodized aluminum
The secret to adjusting a photo
is to isolate the “flash” areas of
the face by making them a
more solid white

Fine material steps
anodized aluminum
Our next step is to open the Unsharp Mask command. Go to
BITMAPS | SHARPEN | UNSHARP MASK

Fine material steps
anodized aluminum
Here is the command window for the Unsharp Mask

Fine material steps
anodized aluminum
Our Image Sharpened

Fine material steps
anodized aluminum
Why Do We Need to Sharpen Our Image?
All photos that we get whether they are scanned in our
from a digital camera have a certain amount of
“fuzziness” applied to them. This is a product of the
process of digitizing a photo. This fuzziness cause an
issue where your eye finds it very hard to distinguish
changes in colours.
To get rid of this fuzziness use a technique called
Unsharp Mask. This technique “sharpens” up the image
by tricking your eye to see a more pronounced
separation between colours

Fine material steps
anodized aluminum
We need to Invert the image as we are placing the image on a
black surface material. Go to EFFECTS|TRANSFORM|INVERT

Fine material steps
anodized aluminum
Here is our image inverted and ready to send to the laser

Fine material steps
anodized aluminum
Here is my finished image lasered on anodized aluminum

Fine material steps
anodized aluminum
Here is a close up of the grayscale photo. Notice the detail in the bracelet

Fine material steps
anodized aluminum
Here is a close up of the black and white photo. Notice the loss of detail

Fine material steps
anodized aluminum
Here is another finished
image lasered on anodized
aluminum

let us now look at the steps to
use to get the image ready to
engrave on a coarse material
-wood

With the image selected go to
BITMAPS | MODE | GRAYSCALE
COARSE MATERIAL
STEPSWOOD PRODUCTS

Image converted to gray. It is too dark so it needs to be
lightened up with the contrast enhancement tool
COARSE MATERIAL
STEPSWOOD PRODUCTS

To access the contrast enhancement tool go to
EFFECTS |ADJUST | CONTRAST ENHANCEMENT
COARSE MATERIAL
STEPSWOOD PRODUCTS

Our image is to dark. The
histogram shows this
COARSE MATERIAL
STEPSWOOD PRODUCTS

COARSE MATERIAL
STEPSWOOD PRODUCTS
Our Image Has Been Adjusted With The Contrast Enhancement

coarse material steps
Wood products
Our next step is to open the Unsharp Mask command. Go to
BITMAPS | SHARPEN | UNSHARP MASK

Wood products
Our Image Sharpened

Wood products
Our next step is too convert our image to black. To do this go
to BITMAPS|MODE|BLACK AND WHITE

Wood products
When we are in the command window your conversion method is Jarvis.
You can adjust the Intensity slider if you want to change the effect

Wood products
Our Image Converted to Black and White

Wood products
Our Image Finished

COARSE MATERIAL
STEPSWOOD PRODUCTS

in my experience fine materials make
better photos than coarse materials.
they hold more detail and thus can
create a better looking photo. thus if
you have the choice to choose your
material choose a fine material

although converting to greyscale in
coreldraw is easy to do there is
better control if we use photopaint.
this is especially true if the image
has what is known as a colour cast.
this is where one colour of the image
- say red - has become dominant do
to proper exposure or lighting

in Corel photopaint we can easily
correct this using the convert to
greyscale command. this is easy to
do and be very quick to fix colour
issues in a photo

New Technique greyscale conversion
via photopaint
Here is my test image. Notice the bias in the red colour in the photo. This
will cause issues when I convert to grey if done in CorelDraw

Send the photo to photopaint from
coreldraw
You can open up the image in PhotoPaint or CorelDraw. Here I have
opened the file in CorelDraw and I can open it in PhotoPaint by right
clicking on the image and select “Edit Bitmap”. I will be able to save the
changes back to the file in CorelDraw

Here is our image in photopaint
Here is our image in PhotoPaint

Access the convert to grayscale
command
To access the Grayscale command we need to go to
IMAGE|CONVERT TO GRAYSCALE

Access the convert to grayscale
command
When we open up the command you have te two window view. There
are also sliders that relate to colour. Each slider allows to add (black) or
subtract (white)

adjust the red in the photo
When we open up the command you have te two window view. There
are also sliders that relate to colour. Each slider allows to add (black) or
subtract (white). I have moved the red slider right.
Before After

Adjust the yellow in the photo
Here is our image adjusted for red (Before). The After photo shows my
yellow adjustment. These two adjustments give me a very good tonality
to the photo as it has reduced the red and yellow
Before After

Adjust the green in the photo
Nothing happens to the image when I adjust the Green.

Adjust the cyan in the photo
Nothing happens to the image when I adjust the Cyan. For that matter
nothing happens we we adjust the Blues or the Magentas

HERE IS A PHOTO THAT NEEDS TO
CROPPED

Resampling a photo
One of the important steps that people fail to utilize
is to adjust their photo so that it it has a proper
resolution. The proper screen resolution for a laser
machine is typically any where from about 100 PPI
150 PPI. The proper resolution though is based on the
fact that the photograph must be size as. Thus if you
are lasering a photo that’s 5 inches the screen
resolution should be 100 PPI to 150 PPI. For this
reason it is important that we note the size and
resolution of our image before we laser our photo.

Resampling a photo
The status bar indicates that the resolution of this
image is 180 dpi by 180 dpi

Resampling a photo
The property bar indicates that the photo is 3.43 inches
wide by 2.405 inches tall

Resampling a photo
If I make my image 8 inches wide then you notice that my screen
resolution has dropped to 77 dpi by 77 dpi. Thus I will need to
increase my resolution of my image. I will use the resample
command.

Resampling a photo
To open the resample command go to BITMAPS|RESAMPLE

Resampling a photo
Here is the resample command opened up. Notice that I have
unchecked the anti-alias button. Our image size is 783 kB

Resampling a photo
I have increased the resolution from 77 dpi 150 dpi. Notice the file
size increased four times - 2.90 MB

Resampling a photo
Rules
When you resize an image you change its resolution
if you increase the size of resolution goes down if you
decrease the size and resolution goes up
When you want to change the size of the image and
keep its resolution the same use the resample
command. If the resolution is not right use the
resample command to fix it
Make sure you know the size of the photo that you
want to laser. This is very important

resolution some important points for
photos
If you are lasering a photograph as a grayscale image
your best printing resolution is 500 or 600 DPI. As we
decease the resolution your image will take on the
look of the a screen. The lower the resolution the
more the screen effect will appear
Grayscale Image Printing

600 DPI Grayscale Image
No Graininess or “Screen” effect

Starting to see a “Screen” effect

Now we see a strong “Screen” effect

photos
If you are lasering a photograph as a black and white
image (error diffusion) you can run any resolution
from 300 up and the look will be the same.
Even lower resolutions of 150 and 200 are good
Black and White Image Printing

photos
This photo shows minimal quality issues
between the lower resolutions. The quality is
there we are just losing some of the amount of
dots that we can laser with a lower resolution

photos
When it comes to grayscale images it is better to run
at 500 or 600 DPI
When it comes to black and white images a
resolution of 300 or 400 should be fine - unless you
are looking for more power because of the increase in
dots
If you run at different resolutions you will need to
adjust your powers or speed to compensate for more
or fewer dots

Cutout lab
On Coarse Materials It is Best to Remove the
Background

Cutout lab
The Background Interferes With the Image

Cutout lab
Our Background is Removed

Cutout lab
Our Image Looks Good

dodge and burn
We have lost the black shirt and hat

dodge and burn
The Dodge Tool Brings Them Back

photos

using a premask is the only way to do
photo on glass

Laser Engraving Photos

Recommended

Recommended

More Related Content

Viewers also liked

Viewers also liked (11)

Similar to Laser Engraving Photos

Similar to Laser Engraving Photos (20)

Recently uploaded

Recently uploaded (20)

Laser Engraving Photos