WaterMarks on Lankan Currency

The Watermarks on Lankan Banknotes are not easy to illustrate except between 1941 and 2006 when the watermark was limited to a region in Banknote with at most light printing which allowed the watermark to be clearly visible when the Banknote was illuminated from behind. The only exception is the cornerstone added in 2005 to denominations Rs500 and higher.
For all other notes there is significant printing on the Banknote to obscure part of the Watermark. In these case watermark text or diagram needs to be interpolated or extrapolated from the watermark region visible.
For Banknotes from 1885 to 1939 they used few components which were integrated to layout the full watermark. These components are more clearly visible on some banknotes than others, and separate line drawing of these components can be scaled to make-up the watermark of banknotes where they are only partly visible. The Darker than background Fonts had a lighter than background shadow which can be easily reproduced within the PhotoShop make-up.

The adopted methodology should be to start with carefully tracing the outline of an enlarged print-out the watermark image on A4 paper. Both the exact dimensions, orientation and thickness of the lines need to be traced so that the drawing can be super-imposed on the watermark image after appropriate scaling. When line drawing the Text, the draftsmen needs to develop a constant font, ignoring slight deviations which is probably noise in the watermark image realised on banknote.

In 2022 summer, a few Watermark paper 1885-1925 were sold on Auction on eBay as well as Spink which permited those to be illustrated properly and are included below.

The attempt is not the traditional line drawing of watermark, but an attempt to visualize it with a consistent Text font line drawings for each series. See a preliminary attempt to display the text on watermarks on Banknotes using standard fonts available freely online.

In Reverse Chronological Order

These are example where I have the paper without printing to show what the line drawing of the watermarks would look like in these case
2010 Rs 5000 Bulbul Image of WM Paper - No need to draw

2010 Rs 1000 Parrot Have WM Paper - No need to draw