Tools for Philatelists – Retroreveal. 
Most of the time, the time-respected tools of tongs, perf gauges, and magnifiers serve the philatelist well. However, newer tools can be of assistance and make the hobby more enjoyable and productive.
Retroreveal © is a program developed by the University of Utah that is free, and on-line at WWW.RETROREVEAL.ORG It works by scanning the document at a high resolution (600 dpi or better). Your scan is uploaded to the site, and in a few minutes or less, a page with 52 different treatments of your scan appears. Some are color filtration, but others are much more sophisticated.
Rather than explaining how it works, let’s see what it can do for us.
. We can read faded or erased writing. In Figure 1, the cancel has faded, and blends in with the cover. Figure 2 clearly shows the cancel of 11 June 1922..
. Cancels or addresses can be enhanced. (Figure 3) The question is what comes after Limerick. Figure 4 shows that it is N.P.B. or Newspaper Branch.
. Disturbed areas or erasures can be seen. Erased cancels are usually stand out. Figure 5 shows a blue crayon obliterating something. After processing through Retro-Reveal, it is possible to read the underlying writing.(Figure 6) which indicates that the letter was “Subject to the provisions of Executive Order 8339”, but the British censor realized that had been applied in error…
. Ink changes or modifications can be seen.
. Closed tears normally show.
What doesn’t it do?
Heavy black cancels on black or dark colored ink are usually impenetrable.
Watermarks usually don’t show.
The best way to see some of its uses is to look in the public galleries on the site where other people have saved their results. Click on the example and wait for it to load to see results. Here are a few interesting ones:
Gallery 30 Beer stamp – Was it cancelled?
Gallery 35 Canada 5¢ – mint or used?
Gallery 100 New Zealand 5 shilling – erased cancel.
Many of the samples are where the cancel is faded or indistinct.
To use the site, first register then follow the instructions. Scan your item to at least 600 dpi and save as a .tif file. For best results, crop your scan to cover only the area of interest. Save it as a .tif file, then upload. Depending on size, it takes 2-3 minutes to create the output.
It doesn’t always perform miracles, but it is a useful to to have on your computer.