Hi,

If I'm reading this correctly, it looks like this document is saying

that at 2.5x magnification, a pixel length of 462 corresponds to a

real length of 2000 micrometers. I'm not sure what the "marker

length" represents however. If I'm correct, then in ImageJ you can go

to the Analyze->Set Scale option and fill in these numbers:

Distance in Pixels = 462

Known Distance = 2000

Pixel Aspect Ratio = 1.0 (usually)

Unit of Length = um

Resulting in a scale of 0.231 pixels per micrometer.

The best way to figure this out on your microscope is to take a

picture at 2.5x magnification of a object of known dimensions (the

ruled spacings on a ruler for example or something more precise like

a hemocytometer grid), draw a line across this distance to get the

pixel length, and then fill in the appropriate numbers again in the

Set Scale option. That way you're not depending on some vague

calibration file like this one to get your image scales right, and

that way you can confirm if the calibration file is correct as well.

John Oreopoulos

On 11-Dec-08, at 12:31 PM, effect10 wrote:

> Dear ImageJ users,

>

> I am quite a newbie on this front so I hope you can help me.

>

> I have made an image of 2.5x magnification. The program I used for

> this

> (research assistent) gives as a calibration:

>

http://n2.nabble.com/file/n1644260/KalibratiePathologie.doc> KalibratiePathologie.doc

>

> I have no idea what is the best way to set this in the set scale

> function of

> ImageJ.

>

> Sorry for this newbie question, but I hope someone will be so kind

> to help

> me out?

> --

> View this message in context:

http://n2.nabble.com/set-scale-in-
> ImageJ--tp1644260p1644260.html

> Sent from the ImageJ mailing list archive at Nabble.com.