Blue Lens Or Filter To Identify Watermarks On Yellow/Orange Stamps

Knowledagble commuinty,

I've always had troubles identifying watermarks on stamps that are printed in yellow or orange Inc. My biggest pain is discriminating between Scott number 260 and number 275. I did read on a website that in order to better visualize these watermarks try viewing the back of the stamp with the watermark fluid while looking through a blue filter or a blue type of lens. It's been really difficult trying to find something like this and I was wondering if there might be something around the house that would work or do you guys have any quick links to products online or items at a hardware store that I could locate easily.

Cheers!

You should be able to buy all kinds of plastic blue/cyan filter sheets online, I got a set on ebay (many shades) for maybe $8.

https://www.ebay.com/itm/3-x-3-75mm...AOSwI~tagRtL

Here is one, $3.95 plus shipping. Best sources are photographic and print shop filters. I can't think why one would be at the hardware store. John

You can wet scan them with lighter fluid and then upload the image with any software package that allows you to modify the image; including tinting

Jack Kelley

I have tried the wet scan and trying to manipulate in software and my success rate was low.

If someone is having better luck, please share your technique.

I have had problems, too, Angore. But it still seems to yield better results than merely watermarking

Jack

What is a "wet scan"?

You apply the watermark fluid while stamp is on scanner glass and then scan.

I watermark the stamp in a tray and then move the wet stamp to the scanner.

Jack Kelley

Adding a color tint to an image would not help; but splitting the color channels (i.e. Retroreveal) to a wet scan may indeed help you to ID a faint watermark. When thinking about images, remember that if you are 'adding' anything then you looking at some software coders work (which may or may not have much to do with reality). But if you are splitting out or removing data, then you are still looking at reality.

As forensic stamp detectives, our job is not to 'Photochop' images by adding or falsely manipulate image data but rather careful analyze the image data as close to the original, uncompressed image as we can get.
Don