Measuring Photo

R
Posted By
Roberto
Jun 19, 2008
Views
292
Replies
4
Status
Closed
Have always wondered what is the measurement when you go to Image-Image-size? Or when you look at the edge rulers?

at full size (or actual pixels) how come it doesn’t measure correctly when you lay a ruler up to the screen?

I’m editing an image and then taking it into Autodesk Inventor and using it as a decal. I need it to be a certain size before that but the measurement is not accurate?
Related Tags
measure

Must-have mockup pack for every graphic designer 🔥🔥🔥

Easy-to-use drag-n-drop Photoshop scene creator with more than 2800 items.

G
Greg
Jun 20, 2008
Chris Darwin wrote:
Have always wondered what is the measurement when you go to Image-Image-size? Or when you look at the edge rulers?

at full size (or actual pixels) how come it doesn’t measure correctly when you lay a ruler up to the screen?

because the apparent size on the screen depends on the pixel pitch of the screen. The ruler displayed by your software – PS, PSP, whatever – is accurate in its measurements of the image, but does not necessarily correspond with a ruler held up to the screen.
I’m editing an image and then taking it into Autodesk Inventor and using it as a decal. I need it to be a certain size before that but the measurement is not accurate?

The size as set or displayed by Image/Image Size is dead accurate when you print the image, provided you have a good printer.

Colin D.
** Posted from http://www.teranews.com **
JJ
John J
Jun 20, 2008
Chris Darwin wrote:
Have always wondered what is the measurement when you go to Image-Image-size? Or when you look at the edge rulers?

Here is the short answer. I hope the experts chime in if I misguide you.

Find out how big the image must be to print to your desired dimensions. The size can be given in pixels, for example 2048 by 4096 (that’s an arbitrary example). Or it can be given in inches at a certain "ppi", usually something like 360ppi. Photoshop shows you ppi (DPI) in the Image Size dialog.

"dpi" is useful only as a number for factoring the actual pixels tall and pixels wide.
R
Roberto
Jun 20, 2008
Colin_D wrote:
Chris Darwin wrote:
Have always wondered what is the measurement when you go to Image-Image-size? Or when you look at the edge rulers?

at full size (or actual pixels) how come it doesn’t measure correctly when you lay a ruler up to the screen?

because the apparent size on the screen depends on the pixel pitch of the screen.

okay, that makes sense

The ruler displayed by your software – PS, PSP, whatever – is accurate in its measurements of the image, but does not necessarily correspond with a ruler held up to the screen.
I’m editing an image and then taking it into Autodesk Inventor and using it as a decal. I need it to be a certain size before that but the measurement is not accurate?

The size as set or displayed by Image/Image Size is dead accurate when you print the image, provided you have a good printer.

Okay that makes sense too.

Here’s what’s happening.

It’s a .BMP and in CS2 it measures 8.25" x 7"

when I insert it into Inventor it measures 6.2" x 5.3"

I resolved the problem when I found you can resize in Inventor however this size thing has always been an issue. I just didn’t understand the relations of screen size, print size, measured size.

Colin D.
** Posted from http://www.teranews.com **
J
jaSPAMc
Jun 20, 2008
John found these unused words:

Chris Darwin wrote:
Have always wondered what is the measurement when you go to Image-Image-size? Or when you look at the edge rulers?

Here is the short answer. I hope the experts chime in if I misguide you.
Find out how big the image must be to print to your desired dimensions. The size can be given in pixels, for example 2048 by 4096 (that’s an arbitrary example). Or it can be given in inches at a certain "ppi", usually something like 360ppi. Photoshop shows you ppi (DPI) in the Image Size dialog.

"dpi" is useful only as a number for factoring the actual pixels tall and pixels wide.

"PPI" is applicble to scanners, meaning that the image is -=created=- with xxx Pixels Per Inch. The scanner’s optical capability may be much higher and many cells may be averaged to produce the final Pixel.

"DPI" is applicable to printers, meaning that the printer will place YYY Dots Per Inch. A dot is the smallest item of resolution, though depending upon your specification for the image, it may represent a Pixel, by many actual dots. EG: IF a printer is capable of 1200 DPI, and your image is sent at 300 DPI, then each Pixel will be represented by a Dot Matrix of 4×4 or 16 ‘dots’. You are asking the printer to ‘fake’ its native resolution for a specific ‘dot size’.

To further confound the terminology, each ‘printer dot’ may be made up of many ‘colour’ dots from the toner or ink.

Both PPI and DPI are the same when stating the image specifications, but aren’t necesary in dimensioning the screen image, just say XXX pixels, by YYY pixels.

Must-have mockup pack for every graphic designer 🔥🔥🔥

Easy-to-use drag-n-drop Photoshop scene creator with more than 2800 items.

Related Discussion Topics

Nice and short text about related topics in discussion sections