X-Ray Timer for Android

Android App Store Link


Now available on Android!  This has been by far my most popular app on iPhone and now it is available for Android also.

This app was modeled after the slide rules that Industrial Radiographers use to estimate their exposure times.

The app has the ability to change between inches and MM, Curies or TBq. It also obviously has a selector for which isotope you are using.

X-Ray Timer Version 4 in App Store

Version 4 is live in the app store which fixes the crashing issue in iOS 10.

If the old version is still on your phone it should auto-update.

If you had deleted it you will have to download the latest version.

X-Ray Timer Crashing in iOS 10

I have removed it from the app store for now.

I will try to analyze the issue and decide how to proceed.

I have heard from many users and it is nice to know people are using the app after all these years.

I am swamped with work so I will try to get on it as soon as I can and decide what to do with it.

Sorry for the issue.

Radiographic Enlargement

I have had a lot of people email and ask about the math formulas to calculate Radiographic Enlargement.

If you look in many of the handbooks and online you will mostly find very complicated formulas.  In reality  it is quite simple and just uses basic ratios.    The formula below is for using a steel comparator ball but the math works the same if regardless.

Actual Pipe Wall = (Actual Ball Diameter ÷ Ball Diameter on Film) X Wall Thickness on Film


Divide the actual ball diameter or the length of the optical comparator by the measured apparent length of the comparitor on the film. Multiply this answer by the pipe wall thickness as measured on the film.

For accurate measurement the ball or comparator block must be put as near as possible to the exact side of the pipe parallel to the film so that the enlargement of the pipe wall is the same as that of the ball of block.

If the comparator or ball is not touching the pipe because of insulation, aim the source at the center of the space between the two, as shown in the drawing below. This will help insure an equal amount of enlargement to the ball and the pipe wall. (Think of how the source side of an elliptical 2” weld is distorted more than the film side)


If using a one inch diameter ball and the diameter measured on the film is actually 1.2 inches and the film wall measured on the film is 0.500”, the actual wall thickness is 0.416 inches.

Pipe Wall = ( 1” ÷ 1.2” ) X 0.500” Pipe Wall = 0.83 X 0.500”
Pipe Wall = 0.416” 



Below is an Excel spreadsheet calculator that you can use.

Radiographic Enlargement Calculator

PDF Version of this article Radiographic_Enlargement

X-Ray Timer Version 3 in App Store

X-Ray Timer has been updated to Version 3.0 and is available in the app store.

The product page for the app with app store link can be found at the link below;


This version adds the ability to use SI units in addition to standard US units of measure.

Other improvements include visual and performance improvements, and retina graphics for the iPhone.

This version requires iOS 5.