Watermarks [gelöst]

I have asked before but no one answered-- What is the best way of detecting watermarks on Banknotes (mainly German )   some one must know

Light behind the note (see Fig. 1)? This would be the most obvious way that comes to mind.

Tried that-must be going blind

UV light in case ordinary light is not helpful

Thankyou guys

Sometimes, especially on the German hyperinflation notes, they can be hard to see or at least to discriminate the types.

At the moment I am trying this machine, and trying to project on computer but Windows10 does not like it

this one has 8 lights

Personally I either use a flash light or one of these quite bright lamps between two boxes and put the banknote (that is in a stiff holder) on top. 

Some of the older series notes from Eastern European nations can be really tough to detect.  The thicker the paper & the more circulated the note- the harder to see the watermark.  Also, some printers produced pattern-like wavy watermarks that are found through the entire design of the note- these can be pretty tough to detect (compared to the simple smaller images which are in a window -no design) as seen most modern notes. 

The newer the series & better the condition/grade- the easier it is to see these pesky subtle images 🤪

thanks for that- it is mainly for German notes inc Notgeld that i struggle- that little light i showed picture of is helping, but my poor olde eyes are strugging  haha