Position RF

Measurements are:
Range ±:
List results:
Item Date:

Use the ± buttons to select the range (number of steps of leeway in either direction) to use when looking for a match. Checking an 'Add' box adds one point to the range for that position only. You may use an asterisk (*) in place of an unsure value, but in ONE box only.

You can restrict the range of plates checked by specifying the colour, the perforation, and Alphabet I or II (leave it on "check both" if unsure which alphabet it is). If the item is on a dated cover or piece, you can also enter the date so as to not show plates that could not have been in use at the time.

The results show the number of steps difference between your measurement and the accepted data. Example: if the result is shown as '-4' and your measurement was '6+', it is four steps below the recorded measurement for that plate/position of '8-' (remember the steps go 6+, 7-, 7, 7+, 8-). A low measurement (closer to the edge of the square) may occur due to excessive inking.

You can either display the results in order of the plate numbers or by "overall closeness" (or "weight", i.e. the sum of the squares of the differences in the number of steps for all four positions). This can help as the exact measurement to read can be a judgement call, so a plate with four close measurements may well be a more likely candidate than one with three exact and one a long way off!

Plating data last updated 20th December 2020

Fisher-Brown Measurements and Plating Notes for Position RF by Plate

Links in blue in the first column are to the colour picture of the registration sheet for the plate on the website of The Postal Museum. A link in red means that this lettering has been removed from the sheet (or there is no sheet for that plate), and goes instead to the appropriate page of Ian Wright's "Missing Imprimatur" database, which may have examples of issued stamps from the plate with this lettering.

The additional plating notes from the books have now been included in this version of the tool, and can be displayed as either the modified and extended set of abbreviations that are used in Mike Batty's revised work A Rearrangement Into Numerical Order of the Fisher-Brown Measurements ..., or as plain English text. You can switch between them, and between showing all plates or just the ones matched above, by clicking the buttons below.

If you think a stamp is from a particular plate, but want to check for alternatives, you can click the "Use" button in the appropriate row to insert the actual measured values for that plate into the search boxes above, then click "Search" to find other plates whose measurements are close.

Please note that these plating notes are being re-examined with the benefit of the latest information, so should be considered as a cross-check for difficult stamps rather than a primary determinant – the letter position measurements should be evaluated first.

Please contact if you come across anything that appears to be incorrect.