By William F. Sharpe
Most collectors are familiar with perforation gauges to measure the distance between stamp perforations. The Scott Multi-Gauge, for example, is accurate enough to measure perforations at least to the nearest tenth perf size.
Perf size is defined as the number of holes or teeth within a length or width of 2 centimeters. If a stamp has 11 perforations in this distance, it is defined as perf 11. A stamp that is perforated gauge 11 by 10.5 has 11 perfs horizontally and 10.5 perfs vertically.
I recently used the computer programs Perfomaster 3000 and ePerforationGauge to measure stamp perfs.
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Performaster automates the measurement of perforations. The program works with either stamp images from any source in BMP, JPG or DIB format or user-scanned stamp images.
The program can be downloaded from the BuxSoft website. It’s completely free for one year’s use. You also can register the program and obtain a free license to use the program beyond the first year.
Performaster originally was written in German, but an English-language version is available.
The full 50-page PDF (portable document format) manual is in German. There is also a simplified 17-page English version, and this shorter version is sufficient for understanding how to use the program.
For best results, Hermann Bux, the author of the program, suggests that stamps be scanned individually at 600 dpi (dots per inch) on a black background.
The black background is especially important so that the perforations can be readily determined.
Be sure to read the tips and techniques section at the end of the manual before starting to use the program. If you don’t download the manual, you can read it from the Help/Support menu choice in the program.
Performaster can scan and process the stamp image automatically or manually. See the nearby illustration with the United States 1952 3¢ NATO stamp as an example (Scott 1008).
For automatic operation you set the program to either start scanning or to load a stamp image from your file system. Pick either scan mode or file mode from the top menu bar control mode drop-down list.
The large button on the far left will start either process, rotate the image to the horizontal position, crop the image to the size of the stamp, and measure the perforations.
Manual operation allows you to view each step as you proceed. Click on the separate steps to the right of the automatic button.
I scanned several stamps at once on my all-in-one HP printer, then used Stamp Image Bursting Application, a program I wrote about in the May 7, 2012, issue of Linn’s, to separate the stamps into individual files.
I also used the scan mode to scan a single stamp. Doing so opened the scanning program for my HP printer so that I could insert the resulting scan directly into Perfomaster.
In addition, you can use the program to determine the distance in millimeters between any two points on your stamp image.
The program ePerforationGauge (ePerf) is essentially an onscreen perf gauge.
The program provides a transparent screen area where you can move a stamp image within guidelines to show the perforations and then measure them.
You need to provide the stamp image already straightened and cropped to show the perforations.
Open ePerf to see the bounding areas as well as the perf listings at the top and left side.
There also are several choices available in the top left corner of the screen.
If you have scanned and saved your stamp image full size, the 100-percent default selection at the top is appropriate.
The next box is for selecting the scan resolution. I used 300 dpi for the stamps I scanned.
The red stop button closes the program.
Open your image-file program — I use Irfanview — and move either the image itself by dragging the top of the program window or, alternately, the perf gauge by dragging any of the four-way arrows so that the perforations are within the red outlines at the top and left side as shown in the nearby illustration, using the 1952 1952 3¢ Lafayette stamp as an example (Scott 1010).
Click on the double arrow at the top left of the stamp to see the top and left side perforation measurement. Move either the gauge or your program so that the perforations show up at the bottom and right side of the stamp.
Click on the double arrow at the lower right of the stamp to see the bottom and right side perforations.
You need to read the summary of the installation and use of the program before using the program. This summary was written by Peter Paul Hek, the author of the program.
Both stamps I measured, Scott 1008 and 1010, should be perf gauge 11 by 10.5.
The perforations on the Lafayette stamp measured 11.25 by 10.5 with both programs.
The perforations on the NATO stamp measured 11.25 by 10.75 using Perfomaster and 11.25 by 10.5 using ePerf. The results are within about 2 percent of the stated perf measurement.
Both of these programs run on Windows 10. They also should run properly on earlier version of Windows.
EzPerf, a program from SoftPro 2010 that I reviewed in my column in the Dec. 3, 2012, issue of Linn’s offers more options than either of the two aforementioned programs.
You can read about EzPerf and download a free fully functional trial version online.