Producing Journal
Quality Images
Using SAS/Graph
Martha Cox
Cancer Outcomes Research Program
CDHA / Dalhousie
Typical requirements
from academic journals
 Image
resolution: 300 dpi
 Printed images usually 6½” wide
What is “dpi?”
DPI is calculated from 2 properties:
pixels: exact number of dots used
horizontally and vertically
to create the image
inches: actual size of the printed image
dpi = pixels / inches
Calculate how to get 300 dpi
for the X axis at 6½” wide:
dpi = pixels / inches
300 = pixels / 6.5
pixels = 1950
Determine the desired
height of the graph
Get the aspect ratio of your figure.
My graph: (x:y) = 7”:5¼”
So, 7:5.25 as 6.5:y
7y = 34.125
y = 4.875
Calculate how to get 300 dpi
for the Y axis:
dpi = pixels / inches
300 = pixels / 4.875
pixels = 1462.5
SAS/Graph options
xpixels & ypixels:
exact number of dots used
horizontally and vertically
xmax & ymax:
actual size of the printed image
SAS/Graph options
x-resolution = xpixels / xmax
y-resolution = ypixels / ymax
SAS/Graph options
for this example
goptions xpixels = 1950
xmax = 6.5
ypixels = 1462.5
ymax = 4.875
;
Produces 300 dpi at 6 ½ “ w x 4⅞” h.
SAS/Graph options
for this example
goptions xpixels = 2100
xmax = 7
ypixels = 1574
ymax = 5.25
;
Produces 300 dpi at 7” w x 5¼” h.
Questions?